Research On Web Service Selection And Composition By Multi-Objective Decision Method Based On Fuzzy QoS

With economic globalization and the rapid development of network, applications of web services quickly occupied the Internet market with its encapsulation, loose coupling and cross-platform advantages.It is also due to these characteristics, most web services have single function and cannot satisfy users repuirements.Thus, it is very neccessary to composite exisiting web services to new web services for users according to the techniques of service selection and service composition. However, there are many shortcomings in these Web applications, such as premature ontology technology on Semantic Web services, service composition based on NP problems. In this paper, we propose a service selection by multi-objective decision method model which based on fuzzy QoS to solve the problem.In this model, the incomplete preferences, vector and weight of QoS are provided by users. In the processes of service selection, it employs adjustable QoS weight deciding by three parts and multi-objective decision method to select the optimal non-inferior services. Then it presents the specific realization process by examples, and proves effective by simulation experiment.And then, the model is preliminarily accomplished web service composition by adopting backtrack method. In the service composition process, it adopts web service selected by multi-objective decision method as the candidate web services, and then composite these candidate web services by backtrack method. In additional, it conducts a simulation experiment that verifies it can reduce the combination service search space and execution time.Lastly, based on above moduls, it realizes the combination of services prototype system in MyEclipse platform, and looks forward to the future work.