|title:||Quiescence in Timed Automata|
Djurre van der Wal
Quiescence, or the absence of outputs is an important notion in model-based testing. A system-under-test (SUT) must fail a certain test case if an output is required, but the SUT does not provide one. Therefore, absence of outputs if often labeled via a special quiescence label, delta.
In practice, it is difficult (and even impossible) to determine if a required output will never be given. Therefore, it is implemented by a time out: if no output occurs after M seconds, then it is assumed that no output will occur anymore.
Therefore, it makes sense to investigate the notion of quiescence by means of timed automata: suppose that we model everything (ie the SUT and the requirements) by means of timed automata, do we then get the same results as before, with the delta-labeling approach?
- study the concept of quiescence
- study timed automata, and the tool Uppaal (see www.uppaal.org)
- transform delta-labeled automata into timed automata
- compare the results