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.