Workflow Instance Migration Responding to Process Evolution

摘要

Workflow processes sometimes need to undergo dynamic evolutions, i.e., changing existing workflows while they are in operation. To manage changes to workflow processes properly, the evolution of workflow instances should be considered. In this paper, we primarily address the upward compatibility issues of models related to structural changes. Upward compatibility is the ability of running workflow instances to migrate to a newer workflow process definition. Regarding this kind of compatibility, we distinguish five levels to identify the degree of compatibility. The analysis techniques of Petri net based on language and reachability graphs can be applied to check the compatibility constraints. By offering a formal foundation for the compatibility analysis of workflow process evolution, this work provides concrete guidelines for redesigning a workflow process model, and successfully migrating of workflow instances..