Study On Workflow Modeling And Analysis Based On Petri Nets

Workflow technology, being an important field of application as computer supported cooperative work, has played a major role in the enterprise process management. Workflow management systems are used to define, create, manage and monitor the execution of workflows. Workflow model (process definition) is a core issue of workflow management system, its quality directly impact on the application of entire workflow management system and the ability to adapt to change.Workflow Management Coalition put forward a XML-based workflow process definition language, which has been a standard of workflow process description language. In fact, it is made the mapping process being independent on different modeling method. Modeling and analysis of workflows based on formalisms are the foundations of the design and development of workflow management systems. Formal models do not leave any scope for ambiguity and increase the potential for analysis. Petri nets are most widely used formalisms for describing and analyzing discrete-event concurrent systems. Combine the respective advantages of XPDL and Petri nets in modeling; this paper gives a mapping method from XPDL to Petri nets. Because of the versatility of XPDL and the mature analysis technology of Petri nets, the model transformation method is universal and practical.Workflow model analysis composes of soundness analysis, reducation analysis and occurrence sequence analysis. An easily understood reducation of workflow model is given in this paper, presented reducation rules, algorithms and proved the correctness of reducation rules.The author analyses the soundness of the workflow model, introduces two kinds of special work WF-Nets: the state machine and marked maps of WF-Nets, and give the proof of soundness. Finally, the occurrence sequence analysis method of the workflow is introduced with a specific example to demonstrate the workflow model validation and confirmed.