Web Combination Of Service Framework Optimization Model And Its System

With the rapid development of e-business, web applications based on the Web are developed from localization to globalization, from B2C (business-to-customer) to B2B(business-to-business), from centralized fashion to decentralized fashion. Composing existing services on Internet to obtain new functionality becomes essential and is conductive to enterprise's efficient application. Web composite service is important and necessary to carry out the research on the new architecture of web services, on the combinations with other good techniques, and on the integration of services.At first, this paper has introduced related technologies on services selection and discovery. Then the paper has proposed a new strategy on composite selection based on composability between basic services in composite service. During the process of selecting optimal composite service, it has converted the traditional complex QoS solution model to a 0-1 based on linear programming model by adding a virtual basic service with its all QoS effect being 1 into candidate service sets corresponding to task in composite service. The new objective function is the optimization problem on QoS of composite serveice, and it's linear to 0-1 variables. These variables mark the state whether coprresponding service is selected. Constraints contain two aspects, users'expectation on QoS and composability between basic services. In the course of problem solving, the conduct of filtering composite service has used advanced implicit enumeration algorithm, which makes solving speed much faster by adding an appropriate constraint. At last, a lot of simulation experiments are done on computer system. The experiment results show that the composite service algorithm proposed by this paper is workable.