Research On The Key Technologies Of Web Services Composition

With the mushroom of the network technology and its application, user's requirements were en-hanced. Thus, various services which were able to satisfy all requirements effectively were expected.The center of gravity for the Network research has been extended to the application layer in Network.The next generation network in the future would be a user-oriented, QoS-assured network which focuseson service. It would provide a lot of various services and has the ability to customize and manage theseservices. In order to enhance competitive preponderance and adaptability, enterprises should enhancetheir agility and ?exibility in response to customer's and market's needs.The business software system should have the ability to compose congruous and available new ser-vices, based on the new requirements in the new Internet environment, utilizing those legacy resources.This has become a challenging problem needing to be resolved imminently. The problem is the result ofdemand-driven.Web Services Composition (WSC) which is growing rapidly could be an excellent approach toachieve all these goals. It supports business agility, ?exibility, and availability–the main features in E-Business software. In the new service-oriented application environment, under the boost of requirements-driven, WSC with QoS-assured has turned into a primary research field in Web Services.In the past few years, many issues have been addressed. In each node of WSC plan (process /flow);there exist lots of Web Services with the same function. How to select a right one exactly in QoS view?Related research had some disadvantages in this problem named Service Selection. On the other hands,with the global Web Services market, there exist a number of WSC plans satisfying functions require-ments. Those plans provide different QoS. How to valuate or optimize them in QoS view? Heretofore,there have not some works on plan valuation/optimization. Weakness in there two aspects hamper thewide deployment of WSC. How to resolve these issues ideally is an open problem.First of all, this paper defines the basic notion, summarizes the initial research and the actualityin related domains. Secondly, a common abstract framework model and a QoS composition model arediscussed in detail. With the production in model aspect, based on Integer Programming (IP) and Multi-objective optimization, a Service Selection algorithm named SS-IP is presented. Subsequently, PlanEvaluation/Optimization is considered and resolved by PlanEO algorithm, based on Analytic HierarchyProcess (AHP) and Net Plan. Furthermore, a prototype system is designed and implemented to validateabove models and algorithms. This prototype system also could be deployed into some real applicationfields. Finally, a conclusion is presented, associating with some expectable trends.Based on utilizing some theories and methods in related fields, we researched on the analysis andmodeling of WSC and presented two models (abstract framework model and QoS composition model)which are more general and ?exible. Then we took an in-depth study in services selection and planvaluation/optimization, and contributed two algorithms (SS-IP and PlanEO). Further more, a prototype...