Synthesis of Timing Parameters Satisfying Safety Properties

Safety properties are crucial when verifying real-time concurrent systems. When reasoning parametrically, i.e., with unknown constants, it is of high interest to infer a set of parameter valuations consistent with such safety properties. We present here algorithms based on the “inverse method” for parametric timed automata: given a reference parameter valuation, it infers a constraint such that, for any valuation satisfying this constraint, the system behaves the same as under the reference valuation in terms of traces, i.e., alternating sequences of locations and actions. Those algorithms do not guarantee the equality of traces, but are significantly quicker, synthesize larger sets of parameter valuations than the original inverse method, and still preserve various properties including safety properties. Those algorithms have been implemented in Imitator II and applied to examples of circuits and protocols.