From Modeling to Simulation of Multi-Agent Systems: an integrated approach and a case study Giancarlo Fortino, Alfredo Garro, and Wilma Russo D.E.I.S. - Università della Calabria, Via P. Bucci, cubo 41C 87036 Rende (CS), Italy {fortino, garro, russow}@deis.unical.it Abstract. In this paper, an integrated approach for the modeling and the valida- tion through simulation of multi-agent systems is proposed. The approach cen- ters on the instantiation of a software development process which specifically includes a simulation phase which makes it possible the validation of a multi- agent system before its actual deployment and execution. The approach uses the Gaia methodology for the analysis and the design, the Agent UML and the Distilled StateCharts for the detailed design, the MAO Framework for the neu- tral-platform implementation of software agents, and a Java-based discrete- event simulation framework for the simulation. The proposed approach is ex- emplified by defining and simulating a multi-agent system concerning with an agent-mediated consumer-driven e-Marketplace which offers mobile agent- based services for searching and buying goods. 1 Introduction Recently, several methodologies supporting analysis, design and implementation of Multi-Agent Systems (MAS) have been proposed in the context of Agent Oriented Software Engineering (AOSE) [17]. Some of the emerging methodologies are Gaia [22], MaSE [7], Prometheus [19], Tropos [1], Message [5], Passi [4], and Adelfe [2]. These notable efforts basically provide a top-down and iterative approach for the modeling and the development of agent-based systems. Although, from the software development life-cycle point of view, such methodologies fully cover the require- ments, architectural design and detailed design, the implementation phase is not well supported [6]. In fact, the design models are hard to map to different target agent platforms since a seamless translation process is usually not provided. Furthermore, none of them supports validation through simulation of the MAS under-development before its actual deployment and execution. Validation through simulation or through formal methods can demonstrate that a MAS correctly behaves according to its speci- fications. In particular, discrete-event simulators are highly required to evaluate how complex MAS work on scales much larger than the scales achievable in real testbeds [21]. This paper proposes an integrated approach for the modeling and the validation through simulation of MAS. The approach centers on the instantiation of a software development process which specifically includes a simulation phase which makes it