A Runtime Dependability Evaluation Framework for Fault Tolerant Web Services

Service-oriented systems are usually built on top of Web service components, which are distributed across the Internet, making dependability a big challenge. In this paper, we propose a runtime dependability evaluation framework for fault tolerant Web services to attack this crucial problem. We first propose a user-collaborative framework for collecting Web service QoS information from both the service providers and service users. Then, Web service QoS models, fault tolerance strategies, and optimal Web service recommendation approaches are presented. Finally, the benefits of the runtime evaluation framework are demonstrated by real-world experiments. As illustrated by the experimental results, our proposed framework makes fault tolerance for distributed service-oriented systems feasible, reconfigurable, and optimized.