Semantic Matching of Web Services Based on Choreographies

Web services facilitate the efficient execution of B2B e-commerce by integrating business processes over the Internet, which needs dynamic and flexible binding of services. However, current Web service standards do not support it. A formal approach for semantic matching of service specifications based on choreographies, i.e., the behavior of Web services, is developed in this paper. It can accurately and automatically discover required services for integrating business processes. Firstly an extended deterministic finite state automaton (EDFA) is proposed by labeling state transitions using binary-tuples (input, output) rather than letters. The automata describe Web services in a more accurate way: the nodes represent states maintained by services; the state transitions represent communication activities of services. The automata depict the temporal sequences of communication activities that describe the behaviors of services. Further, the intersection of two EDFAs is defined. Finally, an algorithm for testing the emptiness of the languages accepted by EDFAs is presented and used to evaluate the compatibility of Web services