Modeling Workflow within Distributed Systems

Workflow management techniques are aiming at supporting business process across organization boundaries. Current techniques are lacking of the formalism tools to model and analyze workflows in 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 tools, we present the concept of 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 defined by Aalst [1]. We also presented the decomposing method of a large scaled workflow network into sub-networks. From our analysis and prove, we draw a very good conclusion that the workflow network composed by self-loop connected sub-networks maintains soundness under proper structure conditions. The methods presented are not only a design language for the specification of complex workflows, but also powerful analysis techniques to verify the workflow procedures.