Verification of XRL: An XML-based workflow language

XRL (eXchangeable Routing Language) is an instance-based workflow language that uses XML for the representation of process definitions and Petri nets for its semantics. Since XRL is instance-based, workflow definitions can be changed on the fly and sent across organizational boundaries. These features are vital for today's dynamic and networked economy. However, the features also enable subtle, but highly disruptive, cross-organizational errors. On-the-fly changes and one-of-a-kind processes are destined to result in errors. Moreover, errors of a cross-organizational nature are difficult to repair. In this paper, we show soundness properties of XRL constructs by using a novel, constructive approach. We also describe a software tool based on XML and Petri-net technologies for verifying XRL workflows.