Byzantine Fault Tolerant Algorithm for Web Services

With the rapid development of web services,its reliability has more and more attentions.To make up for lack of support of the Byzantine Fault Tolerant algorithm for Web Services,A Byzantine Fault Tolerant Algorithm for Web services is proposed considering the features of Web services.There are significant differences between the algorithm and the Castro and Liskov′s well-known practical Byzantine fault tolerance method.We have to create replicas on both sides of communicating web services for building composite web services,while in CLBFT′s method,replicas are created only on the server side.In this paper,replicas on both sides of communicating Web services are created using active replication based on active replication.Receiving Window and Receiving Point are introducted to confirm the batch messages of asynchronous environment which needing synchronizing the timing of the receiving of messages among replicas.The I/O automata model of the algorithm is presented.The algorithm is implemented on testbed which following the standard of TPC-App Benchmark,which verifying the correctness of the algorithm.