A Web Service Composition Method Based On Composition Distance

Web Services are considered as self-contained, self-describing, modular applications that can be published, located, and invoked across the web. Nowadays, more and more applications provided in Web Services technology, an increasing amount of companies and organizations implement their core business and outsource other applications as Web Services over Internet. However, single Web Service cannot satisfy all the functionality needed by the user, it is critical to have a method to compose services using by available Web Service, which is dynamic and meets the user’s personal needs. And the evolution of the Semantic Web Service brings a solid foundation for automatic Web Service composition.This dissertation focuse on the research of the methodology of automatic composition of Semantic Web Services, present a Web Service composition method based on composition distance. The main contributions are as follows:(1) This dissertation analyzes the services from view of the whole Web Service library which contains all the existed Web Services, proposes the conception of Composition Distance, and generats the Composition Distance Vector of the service library. On the basis of the Composition Distance Vector, present a heuristic bidirectional search algorithm for Web Service composition.(2) Applying contrary thinking, to separate Web Services before compose these Web Services. This dissertation proposes the conception of Sub Web Service, and converts the composition of complex Web Services to the composition of simple Sub Web Services by separating complex Web Services into simple Sub Web services. The simulation experiment using the public repositories from Web Service Challenge2008illustrated the effective and efficience of the composition method.(3)The dissertation advances the conception of the composition distance based on semantic Web Service, gives the composition method based on composition distance of semantic Web Services. By constructed an experiment ontology, we illustrated the effective of the service composition method.