Research On SOA-based Runtime Framework Of DEVS Simulation And Its Key Technologies

As SOA is a kind of corporation-oriented conception architecture, importing the basic idea of SOA into Modeling and Simulation (M&S), can improve the sharing capability of simulation resource, to enhance the deploying capability of simulation application and simulation system and to reduce the repeated development of simulation system. Simulation based on SOA becomes one of the hot topics of current M&S domain. Based on SOA, the simulation system development process includes developing, deploying, compositing and distributed running of simulation services. This dissertation focuses on distributed running of simulation services according with DEVS, for the purpose that users need not concern the distributed running details. The main contents of the thesis are included: research of SOA-based Runtime Framework of DEVS Simulation (SRFDS), the states management technology of simulation services, the time synchronizing technology, message routing and the prototype system design and implement. The main work and innovations of this dissertation are as follows.(1) The system architecture of SOA-based Runtime Framework of DEVS Simulation is designed. Under the system architecture, there is not the central controlling node, while the DEVS models are still executed locally and the long-distance communications between the simulation services are implemented by invoking the Web service interface. The SRFDS can support heterogeneity and provide multi-platform for simulation application and development.(2) Based on the research of the similarities and differences between simulation service and commonly business nonstate Web service and the lifecycle process of the simulation service, a simulation service manager in one simulation node is proposed to resolve state management problem of simulation service and ensure the successful running of simulation system.(3) On the basis of analyzing null message in conservative time synchronization algorithm of parallel and distributed simulation, an improved null message based conservative time synchronization algorithm is proposed and the number of sending null message is reduced; Based on the analysis for structure of DEVS simulator and message transfer process, an improved version of DEVS simulator is proposed, as well as a message routing mechanism. Therefore, the running efficiency of the simulation system based on Service-Oriented architecture is improved.(4) A prototype system which aims at validating feasibility of this Runtime Framework is designed and implemented. According to the developed, deployed and composited simulation services, the prototype system can run correctly. The prototype system reflects the advantages of the Service-Oriented architecture and improves the sharing capability of simulation resource.