Semantic Matching of Web Services for Collaborative Business Processes

It is a prerequisite for automating business processes integration to dynamically discover usable web services. A formal approach to semantic matching of web services based on choreographies is presented to support it. First, an extended deterministic finite automaton (EDFA) is proposed by labeling state transitions with binary-tuples (input, output) rather than letters. EDFAs represent services more accurately: the nodes represent the states maintained by the service; the state transitions represent the communication activities of the service. Thus, the automata depicts the temporal sequences of communication activities that describe the behavior of services. Second, the semantics-based intersection of EDFAs is presented and the compatibility of services is evaluated by testing the emptiness of the languages accepted by EDFAs. Finally, component structures are introduced to describe services with two roles: invoking another service and/or being invoked by another service. The compatibility of services can be employed to discover usable services, moreover, to validate collaborative business processes.