Synchronized Petri Net: A Formal Specification Model for Multi Agent Systems Sofia Kouah University of Oum ElBouaghi, Algeria MISC Laboratory, University Mentouri Constantine, Algeria Email: kouah@miscumc.org Djamel Eddine Saïdouni MISC Laboratory, University Mentouri Constantine, Algeria Email: saidouni@miscumc.org Jean Michel Ilié Lip6 Laboratory, University of Paris 6, Paris, France Email: jeanmichel.ilie@upmc.fr —                          ! " !      !    #  $        %   !       $      !   !       &             !  ’    !       !   —(       !  I. INTRODUCTION Multi Agent Systems (MAS for short) form a powerful paradigm to design complex software [7][22][33]. Generally, it resolves complex problems where reactivity, mobility [30], dynamicity and adaptation of the system to uncertain or unpredictable factors should be considered. MAS may be seen as societies made up of autonomous and independent entities, called agents. These agents interact together in order to solve a specific problem or to achieve collectively a common task. Agent is viewed as a computer system situated in some environment and that is capable of executing flexible autonomous actions in this environment in order to meet its design objectives [35] [56].The large majority of applications basedagents are designed by [48]:  Using methodologies based on results of Object Oriented SoftwareEngineering [5][9][34];  Highlighting organizational aspects [17] or relations between various aspects of MAS [10][40][44];  Applying construction techniques of expert systems [19];  Or using formal reasoning, based on Z language [43] or on temporal logic [1]. Then, the domain for designing MAS is becoming very attractive. However, several functionalities of MAS like parallelism, dynamicity and communication may not be easily specified using existing specification models. In fact, these models are not defined specifically for MAS. Therefore, new specification models, new paradigms and new tools are required. Designing safe and sound MAS whose behaviors could be checked before its achievement, calls for a rigorous specification step, assisted by a formal specification model. This model should have a welldefined semantics and being able to take into account all MAS functionalities. Previous efforts toward modeling and verifying MAS can be found in the work of [29] [54]. They are based on reachability graph generation. In our work, this issue can be addressed likewise, by generating reachability graph from SyPN model. Such generation can be easily built by generating all possible firing sequences as follow:  Step 1: start from initial marking.  Step 2: fire all enabled transitions from the current marking (i. e. apply firing rules).  Step 3: reiterate the second step from the new marking until no transition can be enabled. In this context, we are mainly interested by formal specification model of MAS. In this field some basic questions arise:  How to preserve agent’s proprieties, such as autonomy, sociability, awareness...etc.  How to model dynamically agents’ interactions.  Asynchronous is a ubiquitous aspect characterizing concurrent interactions that must be straightforwardly modeled. JOURNAL OF SOFTWARE, VOL. 8, NO. 3, MARCH 2013 587 © 2013 ACADEMY PUBLISHER doi:10.4304/jsw.8.3.587-602