Formal Approach for Compatibility Checking of Orchestrations of Composite Semantic Web Services

Web service composition is the process of combining Web services in order to offer value-added services that meet the increasing complex requirements of business processes. Besides simple Web services described with WSDL, OWL-S language allows to describe composite semantic Web services offering multiple operations using complex control structures. However, it becomes harder to manually check the consistency of orchestrations of such services in order to guarantee their correctness and avoid deadlock and erroneous statuses. In this paper, we first propose a formal method for translating OWL-S composite services into communicating automata using an iterative process which is driven by the control structure of that language. The same approach is also applied to the orchestrator whose description is given in WS-BPEL. Thereafter, we build up the synchronization product of the resulting automata and proceed to its consistency checking in order to unveil any forbidden statuses which depict flaws in that orchestration interaction protocol.