A high performance redundant nested invocation suppression mechanism for active replication fault-tolerant web service

The Simple Object Access Protocol (SOAP) is recognized as a more promising middleware for electronic commerce applications among other leading candidates such as CORBA. The redundant nested invocation (RNI) problem arises when servers in a replicated group issues nested invocations to other server groups in response to a client invocation. Automatic suppression of RNI from active group is always a desirable function, yet this function usually requires careful if not complex design. In our previous work, we have proposed a 3-tier RNI suppression mechanism to solve this problem. In this work, we propose a automatic configuration and single-tier suppression mechanism to improve the performance. Our approach is portable so that the web service running on our platform is able to interact with any other SOAP applications. Our preliminary experiments show that the proposed auto-suppression mechanism is efficient in most cases.