An enhanced model for testing asynchronous communicating systems

This paper studies the problem of testing concurrent systems considered as blackboxes and specified using asynchronous Communicating Finite State Machines. In our previous work [Kim 96], an approach to derive test cases for concurrent systems was developed. The approach addressed the state space explosion problem by introducing a causality relation model and the concept of logical time to express true concurrency. This paper builds on and extends the previous work. The model is enhanced to improve the quality (i.e., verdict capability) of test cases by relaxing the unit-time assumption to any natural number and by presenting a computationally efficient algorithm for deriving the test cases. Finally the approach is generalized to describe timing constraints with any real numbers.