Bayesian Network based QoS Trustworthiness Evaluation Method in Service Oriented Grid

With the converging of grid computing and Web service, grid has extended its territory from traditional computing grid to service oriented grid, aiming to realize coordinated resource sharing and problem solving through service selection and composition. Therefore, selecting credible services for applications becomes a key issue in grid environment. To ensure this, a Bayesian network based approach is presented to evaluate the trustworthiness of grid service. Two new concepts, namely QoS trustworthiness and QoS satisfactoriness, are introduced into the proposed method, which are used to describe the resourcespsila capabilities to provide services and userspsila satisfaction respectively. The approach employs performance history to construct an evaluation model, which ranks the services in terms of their trustworthiness of QoS information and considers degree of consistency in QoS provision. Simulative results show that the proposed approach can effectively enhance trustworthiness of service information and improve reliability of service selection.