Section: Software


libalf : the Automata Learning Framework

Participant : Benedikt Bollig [correspondant] .

libalf is a comprehensive, open-source library for learning finite-state automata covering various well-known learning techniques (such as, Angluin s L * , Biermann, and RPNI, as well as a novel learning algorithm for NFA. libalf is highly flexible and allows for facilely interchanging learning algorithms and combining domain-specific features in a plug-and-play fashion. Its modular design avirtual plantsnd its implementation in C++ make it a flexible platform for adding and engineering further, efficient learning algorithms for new target models (e.g., Büchi automata).

Details on libalf can be found at http://libalf.informatik.rwth-aachen.de/

Mole/Cunf: unfolders for Petri Nets

Participants : Stefan Schwoon [correspondant] , César Rodríguez.

Mole computes, given a safe Petri net, a finite prefix of its unfolding. It is designed to be compatible with other tools, such as PEP and the Model-Checking Kit, which are using the resulting unfolding for reachability checking and other analyses. The tool Mole arose out of earlier work on Petri nets. Details on Mole can be found at http://www.lsv.ens-cachan.fr/~schwoon/tools/mole/

In the context of MExICo, we have created a new tool called Cunf, which is able to handle contextual nets (Petri nets with read arcs). Recent work carried out within MExICo [53] has transformed a preliminary implementation into an efficient tool. While in principle every contextual net can be transformed into an “equivalent” Petri net and then unfolded using Mole, Cunf can take advantage of their special features to do the job faster. More details can be found at http://www.lsv.ens-cachan.fr/~rodrigue/tools/cunf/

COSMOS : a Statistical Model Checker for the Hybrid Automata Stochastic Logic

Participants : Hilal Djafri [correspondant] , Benoît Barbot.

COSMOS is a statistical model checker for the Hybrid Automata Stochastic Logic (HASL). HASL employs Linear Hybrid Automata (LHA), a generalization of Deterministic Timed Automata (DTA), to describe accepting execution paths of a Discrete Event Stochastic Process (DESP), a class of stochastic models which includes, but is not limited to, Markov chains. As a result HASL verification turns out to be a unifying framework where sophisticated temporal reasoning is naturally blended with elaborate reward-based analysis. COSMOS takes as input a DESP (described in terms of a Generalized Stochastic Petri Net), an LHA and an expression Z representing the quantity to be estimated. It returns a confidence interval estimation of Z. COSMOS is written in C++ and is freely available to the research community.

Details on COSMOS can be found at http://www.lsv.ens-cachan.fr/~barbot/cosmos/