Analysis of communication models in web service compositions

In this paper we describe an approach for the verification of Web service compositions defined by sets of BPEL processes. The key aspect of such a verification is the model adopted for representing the communications among the services participating in the composition. Indeed, these communications are asynchronous and buffered in the existing execution frameworks, while most verification approaches assume a synchronous communication model for efficiency reasons. In our approach, we develop a parametric model for describing Web service compositions, which allows us to capture a hierarchy of communication models, ranging from synchronous communications to asynchronous communications with complex buffer structures. Moreover, we develop a technique to associate with a Web service composition the most adequate communication model, i.e., the simplest model that is sufficient to capture all the behaviors of the composition. This way, we can provide an accurate model of a wider class of service composition scenarios, while preserving as much as possible an efficient performance in verification.