Symbolic Model-Checking using ITS-tools

International audienceWe present the symbolic model-checking toolset ITS-tools. The model-checking back-end engine is based on hierarchical set decision diagrams (SDD) and supports reachability, CTL and LTL model-checking, using both classical and original algorithms. As front-end input language, we promote a Guarded Action Language (GAL), a simple yet expressive language for concurrency. Transformations from popular formalisms into GAL are provided enabling fully symbolic model-checking of third party (Uppaal, Spin, Divine...) specifications. The tool design allows to easily build your own transformation, leveraging tools from the meta-modeling community. The ITS-tools additionally come with a user friendly GUI embedded in Eclipse

More Efficient On-the-Fly Verification Methods of Colored Petri Nets

Colored Petri Nets (CP-nets or CPNs) are powerful modeling language for concurrent systems. As for CPNs' model checking, the mainstream method is unfolding that transforms a CPN into an equivalent P/T net. However the equivalent P/T net tends to be too enormous to be handled. As for checking CPN models without unfolding, we present three practical on-the-fly verification methods which are all focused on how to make state space generation more efficient. The first one is a basic one, based on a standard state space generation algorithm, but its efficiency is low. The second one is an overall improvement of the first. The third one sacrifices some applicability for higher efficiency. We implemented the three algorithms and validated great efficiency of latter two algorithms through experimental results

Proceedings of SUMo and CompoNet 2011

International audienc

Recent advances in petri nets and concurrency

CEUR Workshop Proceeding

Compilation de réseaux de Petri (modèles haut niveau et symétries de processus)

Cette thèse s'intéresse à la vérification de systèmes automatisables par model-checking. La question sous-jacente autour de laquelle se construit la contribution est la recherche d'un compromis entre différents objectifs potentiellement contradictoires : la décidabilité des systèmes à vérifier, l'expressivité des formalismes de modélisation, l'efficacité de la vérification, et la certification des outils utilisés. Dans ce but, on choisit de baser la modélisation sur des réseaux de Petri annotés par des langages de programmation réels. Cela implique la semi-décidabilité de la plupart des questions puisque la responsabilité de la terminaison est remise entre les mains du modélisateur (tout comme la terminaison des programmes est de la responsabilité du programmeur). Afin d'exploiter efficacement ces annotations, on choisit ensuite une approche de compilation de modèle qui permet de générer des programmes efficaces dans le langage des annotations, qui sont alors exécutées de la manière la plus efficace. De plus, la compilation est optimisée en tirant partie des spécificités de chaque modèle et nous utilisons l'approche de model-checking explicite qui autorise cette richesse d'annotations tout en facilitant le diagnostique et en restant compatible avec la simulation (les modèles compilés peuvent servir à de la simulation efficace). Enfin, pour combattre l'explosion combinatoire, nous utilisons des techniques de réductions de symétries qui permettent de réduire les temps d'exploration et l'espace mémoire nécessaire.This work focuses on verification of automated systems using model-checking techniques. We focus on a compromise between potentially contradictory goals: decidability of systems to be verified, expressivity of modeling formalisms, efficiency of verification, and certification of used tools. To do so, we use high level Petri nets annotated by real programming languages. This implies the semi-decidability of most of problems because termination is left to the modeler (like termination of programs is left to the programmer). To handle these models, we choose a compilation approach which produces programs in the model annotation language, this allows to execute them efficiently. Moreover, this compilation is optimizing using model peculiarities. However, this rich expressivity leads to the use of explicit model-checking which allows to have rich model annotations but also allows to easily recover errors from verification, and remains compatible with simulation (these compiled models can be used for efficient simulation). Finally, to tackle the state space explosion problem, we use reduction by symmetries techniques which allow to reduce exploration times and state spaces.EVRY-Bib. électronique (912289901) / SudocSudocFranceF

Data decision diagrams for Petri net analysis

Abstract. This paper presents a new data structure, the Data Decision Diagrams, equipped with a mechanism allowing the definition of application-specific operators. This mechanism is based on combination of inductive linear functions offering a large expressiveness while alleviating for the user the burden of hard coding traversals in a shared data structure. We demonstrate the pertinence of our system through the implementation of a verification tool for various classes of Petri nets including self modifying and queuing nets. Topics. Petri Nets, Decision Diagram, System verification.