Research And Analysis On Model For Web Service Composition Based On Workflow Petri Net

In recent years, the Web services of theories and technique obtained a substantial development. Along with the technical of Web services research, development and application, many scholars try to look for a valid Web service composition, verification method, make use of a formal method to depict and analyze Web service composition. The value of the Web service lies in service reuse, the Web service composition is exactly main reuse method. By using the Web service composition technique, we can adapt the changing of the business complications quickly and vivid.Petri net was a modeling tool of graphics and mathematization that can use for many kinds of system. It provides the powerful modeling method for describing and researching the complex systems which have parallel, asynchronous, distribution, randomness etc. So it's very important for modeling and analysis about the Web service composition by using Petri net.Workflow management is a new technology which developed quickly in recent years. In the workflow system, the formal modeling and the analysis technology of the workflows is the foundation of the commercial process organizing and management and the workflow management system design and realization. The flow of the Web services composition process is called Web service flow, so we can model the Web service composition process in foundation of workflow Petri net by using the achievement of workflow system.However, the process of the Web service composition modeling is easy to make a mistake. If the flow definition was discovered mistake after it was used, then the price of repairing will be quite high. Another, maybe the nonessential flow design of the Web service composition will reduce the low efficiency. Therefore, it's extremely essential to analyze model in the modeling process.This paper introduced the Petri net and the Web service composition. On the basis of the analysis about the workflow Petri net, by using the relation between the Web service net and workflow net, we model the Web service composition based on hierarchical Petri net. The process of the modeling mainly unified the workflow Petri net and hierarchical Petri net, using refinement theory, then proposed the rational definition of the WSCN, the method of confirming model rational was given. In the end, it's an example of modeling and analysis.