Transforming OWL-S Process Model into EDFA for Service Discovery

Current Web services standards do not well support automatically discovering and selecting services that can be safely integrated with existing components. Semantic matching of service specifications based on the behaviors of Web services, i.e., the ways a client may interact with the service, can be used to solve the problem. Therefore, the transformation of the OWL-S process model specifying the behaviors of Web services into an extended deterministic finite state automaton (EDFA) is presented in this paper. The automata describe Web services in a more accurate way: the nodes represent states maintained by services; the state transitions labelled by binary-tuples (input, output) rather than letters represent communication activities of services; moreover, the automaton structures describe the temporal sequences of communication activities that represent the behaviors of Web services. The compatibility of Web services can be evaluated with testing the emptiness of the languages accepted by EDFAs