Research On Distributed System Testing Method And Its Application

With the development of middle-ware and network technology, distributed system has also been promoted . Currently, distributed system has become the main choice for network applicati- ons, and its application areas are expending. So the quality assurance of distributed system becomes important, and the testing method of distributed system also becomes a research hotpot.When testing a system that has multiple physically distributed ports/interfaces it is normal to place a tester at each port. Each tester observes only the events at its port and it is known that this can lead to additional controllability problems and observability problems. While such controlab- ility problems can be overcome by the exchange of external coordination messages between the testers, this requires the deployment of an external network and may thus increase the costs of testing. Two problems are considered in this paper. The first problem is finding a minimum number of coordination channels to overcome controllability problems in distributed testing. The second problem is how to reduce the number of coordination messages.Controllability and observability problems existing in distributed testing system are researched. A solution is proposed on those problems about controllability problems, observa- bility problems and timing issues. Based on distributed architecture, testers exchange coordination messages to each other through communication media which independs on IUT. The method of local test sequence generation is improved in this paper. Finally, local test sequence generation algorithm based on coordination test method is proposed.At last, when the coordination test method is used in the test of CRM software, it has obtained good performances. The result shows that the coordination channels between the testers are reduced as well as the number of coordination messages.