Modeling and Simulation of Systems of Systems – a Survey <s> Service Oriented Application of the DEVS unified process <s> A recent DoD mandate requires that the DoD Architecture Framework (DoDAF) be adopted to express high-level system and operational requirements and architectures. DoDAF is the basis for integrated architectures and provides broad levels of specification related to operational, system, and technical views. The combination of DoDAF operational views, which capture the requirements of the architecture, and systems views, which provide its technical attributes, forms the basis for semi-automated construction of the needed simulation models. Unfortunately, DoDAF doesn’t mandate any simulation methodology to analyze the system or perform any pre-design feasibility studies. In this paper, we describe an approach to support specification of DoDAF architectures within a development environment based on DEVS (Discrete Event System Specification). The result is an enhanced system life cycle development process that includes both development and testing in an integral manner. We introduce two new operational views (OVs) in the current DoDAF making way for modeling and simulation as a part of the design process. We illustrate the process to build these new OVs from the existing OVs and their impact on the overall DoDAF system development process. We discuss automated model generation using XML through the introduced OVs, which paves the way for OVs to become service-providing components in the web services architecture. <s> BIB001 </s> Modeling and Simulation of Systems of Systems – a Survey <s> Service Oriented Application of the DEVS unified process <s> Preface ix About the Editor xi Contributors xiii 1. Introduction to System of Systems 1 Mo Jamshidi 2. An Open Systems Approach to System of Systems Engineering 21 Cyrus Azani 3. Engineering of a System of Systems 44 Gary D. Wells and Andrew P. Sage 4. System of Systems Architecting 77 Cihan H. Dagli and Nil Kilicay-Ergin 5. Modeling and Simulation for Systems of Systems Engineering 101 Saurabh Mittal, Bernard P. Zeigler, Jose L. Risco Martin, Ferat Sahin, and Mo Jamshidi 6. Net Centricity and System of Systems 150 Robert J. Cloutier, Michael J. DiMario, and Hans W. Polzer 7. Emergence in System of Systems 169 Charles B. Keating 8. System of Systems Management 191 Brian Sauser, John Boardman, and Alex Gorod 9. Systems Engineering for Department of Defense Systems of Systems 218 Judith S. Dahmann 10. Boeing's SoSE Approach to e-Enabling Commercial Airlines 232 George F. Wilber 11. System of Systems Perspectives on Infrastructures 257 Wil A.H. Thissen and Paulien M. Herder 12. Advances in Wireless Sensor Networks: A Case Study in System of Systems Perspective 275 Prasanna Sridhar, Asad M. Madni, and Mo Jamshidi 13. A System of Systems View of Services 293 James M. Tien 14. System of Systems Engineering in Space Exploration 317 Steven D. Jolly and Brian K. Muirhead 15. Communication and Navigation Networks in Space System of Systems 348 Kul B. Bhasin and Jeffrey L. Hayden 16. Operation and Control of Electrical Power Systems 385 Petr Korba and Ian A. Hiskens 17. Future Transportation Fuel System of Systems 409 Michael Duffy, Bobi Garrett, Cynthia Riley, and Debra Sandor 18. Sustainable Environmental Management from a System of Systems Engineering Perspective 443 Keith W. Hipel, Amer Obeidi, Liping Fang, and D. Marc Kilgour 19. Robotic Swarms as System of Systems 482 Ferat Sahin 20. Understanding Transportation as a System of Systems Problem 520 Daniel A. DeLaurentis 21. Health Care System of Systems 542 Nilmini Wickramasinghe, Suresh Chalasani, Rajendra V. Boppana, and Asad M. Madni 22. System of Systems Engineering of GEOSS 551 Ryosuke Shibasaki and Jay S. Pearlman Author Index 573 Subject Index 576 <s> BIB002
The Branching Model-Continuity process undergoes further refinement and integrates together with various elements as automated DEVS model generation tool or automated test-model generation utility via network-oriented simulation procedure over SOA to produce the DEVSUP  Various forms of requirement specifications -state-based, natural language based, rule-based, BPMN/BPEL-based and DoDAF-based are analyzed and the automated process, used by each one to deliver DEVS hierarchical models and DEVS state machines, is evaluated  . In this case the simulation execution is more sophisticated than simple execution of a model on a single machine. With grid applications and multiprocessor collaborative computing, a network-oriented platform using XML as middleware results in an infrastructure, that supports the distributed collaboration and model reuse. The infrastructure provides for platformfree specification language, DEVSML and network-oriented execution using Service-Oriented Architecture DEVS/SOA  . Both DEVSML and DEVS/SOA provide a novel approach to integrate, collaborate and remotely execute complex system models on SOA. This infrastructure supports automated procedures for testcase generation leading to test models. Using XML for the system specifications in a rule-based format, a new tool (Automated Test-Case Generator (ATC-Gen)) is developed to facilitate the automated development of test models  . The integration between DEVSML and DEVS/SOA is shown in Fig. 7 .1. Various model specification formalisms are supported and mapped onto DEVSML models: UML state charts, exhibit-driven state-based approach  , Business Process Modeling Notations (BPMN), Business Process Execution Language (BPEL)  or DoDAF-based specifications BIB001 . A translated DEVSML model is supplied to the DEVSML client that makes coordination together with the DEVSML server utility. When the client operates with DEVS-JAVA models, a DEVSML server can be used to compile the client's model with the other models available at other sites to obtain an enhanced integrated DEVSML file that can produce a coupled DEVSML model. The adopted DEVS/SOA server can use this integrated DEVSML file to distribute the component models at selected DEVS web-server simulation engines. The resulting distributed simulation, or alternatively, a real-time distributed run of the coupled model is the final point of the design process. DEVSML represents DEVS models in XML language format. The DEVSML utility is built on JAVAML (Java Modeling Language), which is XML implementation of Java. The current development popularity of DEVSML follows from the underlying JAVAML, that serves for specifying the "behavior" logic of atomic and coupled models in a SoS application. The DEVSML models have the unique feature of being transformable back and forth to Java and to DEVSML. This feature provides interoperability between various models and an option to create dynamic scenarios. The DEVSML concept is represented in Fig. 7 .2. It demonstrates a layered architecture. At the top level, the application layer is situated. It contains a system model in one of the several formats at DEVS-JAVA or DEVSML. The second level contains the DEVSML layer. It provides integration, composition and dynamic scenario constructing, that results in fully completed portable DEVSML models. They are transferred to any remote location via the network-oriented infrastructure and are able for execution there. Another advantage of such capability is the total simulator transparency during model execution on network-oriented infrastructures. The DEVSML model files in XML description contain meta-data information about the compliance with other simulation components or software versions to provide interoperability between various simulator engines. This property is achieved for at least a couple of independent simulation engines, as they have DEVS protocol to contact each other. This feature is realized by applying a single atomic DTD and a single coupled DTD for validating the DEVSML descriptions, generated by these two implementations. This type of run-time interoperability provides advantages when composing larger coupled models from models on different nodes using the DEVSML integration capabilities  . 7.2. DEVS/SOA: Network-oriented execution using simulation services The fundamental concept of web-based services aims to integrate the software applications as series of tasks. The use of Web services allows the application to communicate with others via open standards. The DEVS-based simulators are applying as Web service. They must incorporate the following standard options: • Communication protocol (Simple Object Access Protocol, SOAP); • Service description (Web Service description Language, WSDL); • Service discovery tool (Universal Description, Discovery and Integration, UDDI). The complete set of components requires one or more servers for DEVS simulation services (Fig. 7.3 ). The ability of running simulations is provided by the server design with DEVS Simulation protocol, supported by DEVS-JAVA, Version 3.1 [1] . The framework for simulation is organized as a two-layered application. The top level contains the user coordination layer, which executes the task for observation the subordinate lower layer. The lower level contains the simulation service layer that executes the DEVS simulation protocol as a dedicated service. At the next stage of the multistep DEVS model generation is the simulation of generated models. The DEVS/SOA client obtains set of DEVS models to perform series of operations via dedicated servers for web hosting of simulation services: (i) Upload the models to particular IP locations, i.e. make partitioning; (ii) Performing run-time compilation at respective sites; (iii) Simulating the coupled model; (iv) Obtaining the simulation output at client's finish. The specified main server houses the top level coupled model and emulates a coordinator that generates simulators in the same residence and/or on other servers. An important feature of DEVS/SOA is the multi-platform simulation capability. It organizes distributed simulation among different DEVS platforms or simulator utilities, (DEVS-JAVA, DEVS-C++, etc.), on Windows or Linux platforms. The system is supplied with simulation services on specific platforms, managed by a single coordinator. In simulation, the overall model is partitioned according to the application platforms and executed by the appropriate simulation service. This is a form of interoperability, where multi-platform simulations are executed with DEVSML integration facilities. DEVSML is used to describe the whole hybrid model. At this stage, the message passing is realized by means of an adapter pattern in the design of the "message" class  . In Fig. 7 .4, the Interoperability DEVS Simulation protocol is shown. The platform-specific simulator generates messages or event flags, but the simulation services transform them into PIMs, according to DEVS/SOA. Hence, the DEVS/SOA framework can be extended for network testing. It needs to have multi-platform simulation capabilities to achieve interaction as Services for concurrent test models on any DEVS environment (e.g., Java, C++). The complete Overall DEVS Unified Process (DEVSUP) design procedure BIB002 consists in the following general steps: (i) Developing system requirements in format BPMN, DoDAF, Natural Language Processing (NLP), UML or DEVS-based; (ii) By the DEVS-based automated model generation utility, generate atomic and coupled DEVS models from the requirement specifications via XML; (iii) Validate obtained PIMs by DEVS V3C to prove their network capability for collaborative development and implement via DEVSML; (iv) Following Step (ii), either coupled model is simulated via DEVS/SOA, or a test image of the DEVS models is generated; (v) The simulation is running in real-time or in logical time on a stand-by machine or distributed environment using SOA middleware for network execution; (vi) The test image of the DEVS models is executed as described in Step (v); (vii) The results are comparing in a Verification and Validation process. The system development of DEVS by the Branching Model Continuity-based Life-cycle process for system engineering is performed on Fig. 7 .5. 