Research And Implementation Of Dynamic Web Services Composition System Supported By QoS

With the development of economic globalization, more and more commercial organizations come into deal with their business in a world-wide field. In order to be suitable for the changing market with growing competition, many business companies have begun to issue their professional business processes as Web Services onto the Internet to provide services for their partners. Strongly stimulated by the market requirement, Web Services composition now has been as a hotspot studied by academic and industrial organizations and it has also become one of important methods to realize dynamic business process.This paper intensively analyzed the interrelated solutions and technologies in the field of composition services. After having synthetically studied up-to-date technologies of Web Services and Workflow, the author putted forward a solution, which supported by business specific QoS criteria to compose Web Services, and presented the architecture of the whole project. This project supports dynamic binding of Web Services, automatic and semiautomatic executions and optimal choice of Web Services based on QoS and so on. Having deeply analyzed main-stream Business Process Modeling Languages for Web Services, we adopted the BPEL4WS1.1 specification as Business Process Modeling Description Language of our project, and presented key components in this scheme, such as the detailed design and implement of Web Services Composition Engine and showed the feature of this scheme by an application instance.For the purpose of distinguishing Web Services which have same functions, we extended WSDL and UDDI to support QoS, and given the model of QoS of Web Services, computation model of QoS and its optimal algorithm, and also shown a fair, opening, dynamic prototype of QoS management framework for Web Services.During the course of research, we also considered and tracked new evolution in this domain. We primarily studied and analyzed the influence on composing services that brought by recently arose WSRF technology, and extended our project to support the WSRF circumstance. Finally, we summarized all our research works and presented the next step's works in the future.