A Fault-Tolerant Strategy for Improving the Reliability of Service Composition

Service composition is an important means for integrating the individual Web services for creating new value added systems that satisfy complex demands. Since, Web services exist in the heterogeneous environments on the Internet, study on how to guarantee the reliability of service composition in a distributed, dynamic and complex environment becomes more and more important. This paper proposes a service composition net(SCN) and fault-tolerant strategy to improve the reliability of service composition. The strategy consists of static strategy, dynamic strategy and exception handling mechanism, which can be used to dynamically adjust component service for achieving good reliability as well as good overall performance. SCN is adopted to model different components of service composition. The fault detection and fault recovery mechanisms are also considered. Based on the constructed model, theories of Petri nets help prove the consistency of processing states and the effectiveness of the strategy. A case study of Export Service illustrates the feasibility of proposed method.