Compatibility Analysis and Mediation-Aided Composition for BPEL Services

In Service Oriented Architecture (SOA), the need for inter-service compatibility analysis has gone beyond what existing service composition/ verification approaches can handle. Given two services whose interface invocation constraints are described by Business Process Execution Language for Web Services (BPEL4WS, or BPEL), we analyze their compatibility and adopt mediation as a light weight approach, to make partial compatible services work together more adaptively, without changing their internal logic. We transform BPEL into service workflow net which is a kind of colored Petri net. Based on this formalism we first analyze the compatibility of two services, and then devise an approach to check whether there exists any message mediation so that their mediation-aided composition will not violate the constraints imposed by either side. Later the method for mediation generation is also introduced. Our approach is validated through a real life case and further research directions are pointed out.