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arXiv · 1806.08170

Universal Safety for Timed Petri Nets is PSPACE-complete

Parosh Aziz Abdulla·Mohamed Faouzi Atig·Radu Ciobanu·Richard Mayr·Patrick Totzke
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Abstract

A timed network consists of an arbitrary number of initially identical 1-clock timed automata, interacting via hand-shake communication. In this setting there is no unique central controller, since all automata are initially identical. We consider the universal safety problem for such controller-less timed networks, i.e., verifying that a bad event (enabling some given transition) is impossible regardless of the size of the network. This universal safety problem is dual to the existential coverability problem for timed-arc Petri nets, i.e., does there exist a number $m$ of tokens, such that starting with $m$ tokens in a given place, and none in the other places, some given transition is eventually enabled. We show that these problems are PSPACE-complete.

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Parosh Aziz Abdulla, Mohamed Faouzi Atig, Radu Ciobanu, Richard Mayr, Patrick Totzke. 2018-06-21. Universal Safety for Timed Petri Nets is PSPACE-complete. https://arxiv.org/abs/1806.08170

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