Using Stateful Activities to Facilitate Monitoring and Repair in Workflow Choreographies

The repair of faulty processes (workflows, web service compositions) needs information about the state of the involved Web services. We introduce an architecture where (Web service based) activities and their instances are treated as manageable resources. Based on the WAMO Model our activities provide detailed information about the state they currently hold, possible states they can reach, as well as operations to affect the current state. The strength of this approach is that we can introduce independent repair and monitoring facilities, that utilize a generic way to access information about running activities.