Analyzing the Impact of Process Change Operations on Time-Aware Processes

The proper handling of temporal constraints is crucial in many application domains. Contemporary process-aware information systems, however, still lack a sophisticated support of time-aware processes. As a particular challenge, by nature, (most) time-aware processes need to be quite flexible as time can neither be slowed down nor stopped. Hence it must be possible to dynamically adapt a time-aware process instance in order to cope with unforeseen events. In turn, when applying dynamic changes to a time-aware process it crucial that the resulting process instance is again sound as well as temporally consistent; i.e., it must still be possible to complete the process instance without violating any of its temporal constraints. This paper extends existing process change operations, which ensure soundness of the resulting process instance, by additionally considering temporal constraints. Furthermore, it provides pre- and post-conditions that ensure that the resulting process instance is again temporally consistent. Finally, we analyze the impact a change has on the overall temporal properties of a process instance and---based on the results---provide means to significantly reduce the complexity of the required time calculations. The latter is crucial to ensure scalability of the approach. The approach has been prototypically implemented in the AristaFlow BPM Suite.