verification support for workflow design with uml activity graphs
We describe a tool that supports verification of workflow models specified in UML activity graphs. The tool translates an activity graph into an input format for a model checker according to a semantics we published earlier. With the model checker arbitrary propositional requirements can be checked against the input model. If a requirement fails to hold an error trace is returned by the model checker. The tool automatically translates such an error trace into an activity graph trace by high-lighting a corresponding path in the activity graph. One of the problems that is dealt with is that model checkers require a finite state space whereas workflow models in general have an infinite state space. Another problem is that strong fairness is necessary to obtain realistic results. Only model checkers that use a special model checking algorithm for strong fairness are suitable for verifying workflow models. We analyse the structure of the state space. We illustrate our approach with some example verifications.
verification support workflow design uml activation graph tool model input model checking semantic requirements errors traces space general fairness use algorithm structure examples lighting