Towards EPC Semantics based on State and Context

Abstract: The semantics of the OR-join have been discussed for some time, in the context of EPCs, but also in the context of other business process modeling languages like YAWL. In this paper, we show that the existing solutions are not satisfactory from the intuition of the modeler. Furthermore, we present a novel approach towards the definition of EPC semantics based on state and context. The approach uses two types of annotations for arcs. Like in some of the other approaches, arcs are annotated with positive and negative tokens. Moreover, each arc has a context status denoting whether a positive token may still arrive. Using a four-phase approach tokens and statuses are propagated thus yielding a new kind of semantics which overcomes some of the wellknown problems related to OR-joins in EPCs.