Passive Testing of Timed Systems with Timeouts

This paper presents a framework to perform passive testing for systems where time aspects affect their behavior. Temporal aspects can be associated with both performance of actions and delays/timeouts. Actually, timeouts have the capability of affecting the subsequent behaviors of the system. Therefore, the expected functional behavior of the studied systems must take into account the possible timeouts. In our approach, so called invariants represent the most relevant expected properties of the implementation under test. We present algorithms to decide both the correctness of the proposed invariants with respect to a given specification and the correctness of the traces extracted from the implementation under test with respect to a set of invariants. The soundness of the method related to a specific implementation relation is also shown.