Out-of-order Evaluation of Timed Petri Nets for Distributed Monitoring

Olivier Baldellon (1) , Matthieu Roy (1) , Jean-Charles Fabre (1)

1 LAAS-TSF - Équipe Tolérance aux fautes et Sûreté de Fonctionnement informatique

Modern embedded systems for safety critical applications, found in planes or cars, are based on real-time distributed networks and require high level of robustness, reliability and adaptability. In order to complement static off-line validation of such systems, this paper introduces a novel approach for on-line verification of behavioral properties expressed as a sub-family of timed Petri nets. We show that, for the subclass of acyclic safe nets, whose expressivity matches real-time systems constraints, it is possible to define a commutative and associative operation on states that enables out-of-order evaluation of the state of the Petri net, and thus a fully distributed evaluation of the behavior of the system under supervision. Additionally, when provided with a mapping between events and nodes of the distributed system, we show how to efficiently distribute the monitoring system on top of the applicative system, and provide algorithms for local evaluation and merging of information in order to detect as soon as possible when the system deviates from its specification.

Mots clés: Arc-Timed Petri nets; Distributed Algorithm; Monitoring; Real Time Systems

Domaines: Calcul parallèle, distribué et partagé [cs.DC]

Olivier Baldellon, Matthieu Roy, Jean-Charles Fabre. Out-of-order Evaluation of Timed Petri Nets for Distributed Monitoring. 2011. ⟨hal-00643683⟩