A study on the replaceability of context-aware middleware

In context-ware computing paradigm, context-aware middleware plays a key role. The middleware collects and manipulates contexts from environments, providing context-aware applications well-defined interfaces to adapt their behaviors when environments change. However, some minor difference in the implementation of context-aware middleware may cause the same context-aware application behave differently. Such behavior deviation may lead to serious problems or even disasters for a context-aware application. It is thus desirable to check whether a mobile context-aware application behaves consistently before moving it from one middleware to another, or whether a context-aware application still works correctly when upgrading the underlying middleware? Existing approaches for context-aware applications are not adequate for detecting such behavior deviation because these approaches do not consider the impacts of the difference in the middleware implementation. In this paper, we study the strategies in the implementation of context-aware middleware and their impacts on the behavior of context-aware applications. By exploring the implied scenarios where a context-aware application may behave differently, new testing approach is proposed to detect the behavior deviation of a context-aware application running on different middleware by generating test cases to cover these implied scenarios.