Addressing soundness and efficiency issues in dynamic processes: a reflective PN-based modeling approach

ABSTRACT

The design of dynamic workflows needs adequate modeling formalisms and tools to soundly handle changes during workflow operation. A common approach is to pollute workflow design with details that do not regard the current behavior, but rather evolution. That hampers analysis, reuse and maintenance in general. We propose and discuss the adoption of a recent Petri net-based reflective model as a support to dynamic workflow design. Keeping separated functional aspects from evolution, results in a dynamic workflow model merging flexibility and ability of formally verifying basic workflow properties. A structural characterization of sound dynamic workflows is adopted. An application to a well localized problem is presented: how to determine what tasks should be redone and which ones do not when transferring a workflow instance from an old to a new template.

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INDEX TERMS

Keywords:
evolution, petri nets, processes, reflection