A Credible Composite Service Based On D - S Evidence Theory Research

Web service is an effective solution in next-generation service-oriented computing, but in an open, dynamic network environment, its authenticity is uncertain, lead to the quality of services portfolio cannot be guaranteed, so how to analyze and assessment the services trustworthiness, as well as select the trusted Web services to combine is an important content of Web service study. In addition, because among Web services exist individual differences, so even select trustworthiness Web services to be combined, how to measure the effectiveness of the results, is also an important consideration.This thesis analyzes various kinds of trusted services composition theory and related technologies over the recent years, and on this basis, focuses on researching the QoS trustworthiness evaluation and the composition service selection strategy. First of all, using the DS evidence theory, and based on the history record information of services with each other, building a model of QoS trustworthiness evaluation. The model discusses services trustworthiness measure, transfer and other issues from the public trust and private trust, so the evaluation results can be more reasonable, and optimize the service choice behavior. Second, For how to measure the validity of the service composition, building a model of the composition service selection strategy based on trustworthiness of QoS, also introduces the correlation degree to characterize the degree of correlation between the basic Web services, and as the standard to measure the validity of the services composition, then we can choose an effective program of composition services, at the same time make the quality of composition service more secure.The simulation experiment results show that using the public trust and the private trust evaluate QoS trustworthiness, the evaluation results can more objectively reflect the services the trust situation, thus improving the success rate of service requests. In addition, using the correlation degree between the services, the composition services can be combined with better.