Interoperability testing based on a fault model for a system of communicating FSMs

This paper presents a fault model for interoperability testing of communication protocols that are modeled by communicating finite state machines, and proposes a technique that extends an initial interoperability test suite, which is given by another existing method, to be a test suite that can detect "almost all" interaction faults based on the fault model. We start with an interoperability test suite derived by a known method and develop a technique for the fault coverage analysis and a technique for the extension of the test suite in order to achieve high fault coverage. We illustrate the proposed techniques with TCP protocol. The fault coverage analysis concludes that the test suite has 100% fault coverage with respect to the proposed fault domain and does not need to be extended. It is shown that our method is applicable to practical protocols and can be used to make interoperability test suites have high fault-detecting capability.