Modeling workflow within distributed systems

Workflow management techniques are aimed at supporting business processes across organizational boundaries. Current techniques lack the formal tools to model and analyze workflows on a large scale, and current WFMSs do not have the ability to react to the response of another WFMS dynamically. Using Petri nets as the modeling tool, we present the concept of a standard workflow structure, and a set of standard workflow blocks are designed. We prove that modeling a workflow process in standard workflow structures can guarantee the soundness of a workflow network as defined by W.M.P. van der Aalst (1998). We also present a method of decomposing a large-scale workflow network into sub-networks. From our analysis and proof, we draw the very good conclusion that a workflow network composed of self-loop-connected sub-networks maintains soundness under proper structural conditions. The method presented is not only a design language for the specification of complex workflows, but also a powerful analysis technique to verify the workflow procedures.