Timed Probability Petri Nets Theory And Analyses In The NCOW System

Network Centric Operations and Warfare (NCOW) is a revolution of the war, not only in the appearance, but also in the essence. Together with NCOW, the Department of Defense of the US starts the project Global Information Grid (GIG). The technology of Grid based on the Web Service provides a solid foundation for NCOW and is the basic idea of GIG system. A powerful method is needed for modeling and analyzing the system of NCOW, to avoid fatal mistake in such an enormous and complex system, also to help to plan and evolve the system.Answer to this requirement, Petri Nets plays an important role in the analyzing of NCOW system. However, according to the unique characteristic of the NCOW system, a new type of Petri Nets is required. That is why the Timed Probability Petri Nets (TPPN) is created in this paper. TPPN solved the problem that usual Petri Nets is not able to describe the uncertainty in the NCOW system while the other type of Petri Nets is too complex to express or difficult to read.TPPN accords with the requirement of the modeling and analyzing the NCOW system, describes the uncertainty in the NCOW system and maintains the concision of basic Petri Nets. Mean while, TTPN could be a good theory foundation to detect key services in NCOW system, which is built on the Grid based on Web Services. TPPN shows how to describe the uncertain information act in the system and which services are most critical to the time response of the whole system. These opinions could be very important to the plan and modification of systems.To support the idea of TPPN, a software tool VisualPN (VPN) is developed to build and analyzing the TPPN model of actual system. VPN tool will help to transfer TPPN from conception to reality, it describes the uncertainty and time property of events occur in the NCOW system. And VPN tool also could have a future in the engineering uses.Finally, a case of Expeditionary Strike Groups (ESG) of the US Navy is showed as a example of a actual NCOW system. TTPN theory is used to build the model and analyzing the performance of this system, with the help of the VPN tool. It shows how to use TTPN theory in modeling and analyzing actual system, and what kind of opinions would be given by the analyses of the TPPN model to the planning, building and modifying the actual systems.