Timed CSP = Closed Timed Safety Automata

Abstract We study the expressive power of an augmented version of Timed CSP and show that it is precisely equal to that of closed timed automatatimed automata with closed invariant and enabling clock constraints. We also show that this new version of Timed CSP is expressive enough to capture the most widely used specifications on timed systems as refinements between processes, and moreover that refinement checking is amenable to digitisation analysis. As a result, we are able to verify some of the most important timed specifications, including branching-time liveness properties such as timestop-freedom and constant availability, using the model checker FDR (a commercial product of Formal Systems (Europe) Ltd.).

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