While temporal logic in its various forms has proven essential to reason about reactive systems, agent-based scenarios are typically specified by considering high-level agents attitudes. In particular, specification languages based on epistemic logic [7], or logics for knowledge, have proven useful in a variety of areas including robotics, security protocols, web-services, etc. For example, security specifications involving anonymity [4] are known to be naturally expressible in epistemic formalisms as they explicitly state the lack of different kinds of knowledge of the principals.More generally, various extensions of temporal logic have been studied in agents and AI contexts to represent properties of autonomous systems. In addition to epistemic operators, at the very core of these approaches is the importance of deontic modalities expressing norms and compliance/violation with respect to previously agreed commitments, and ATL-like modalities expressing cooperation among agents.While these languages have been long explored and appropriate semantics developed, until recently there has been a remarkable gap in the availability of efficient symbolic model checking toolkits supporting these. In this paper we describe MCMAS, a symbolic model checker specifically tailored to agent-based specifications and scenarios. MCMAS [12] supports specifications based on CTL, epistemic logic (including operators of common and distributed knowledge) [7], Alternating Time Logic [2], and deontic modalities for correctness [16]. The release described in this abstract is a complete rebuild of a preliminary experimental checker [14]. The model input language includes variables and basic types and it implements the semantics of interpreted systems, thereby naturally supporting the modularity present in agent-based systems. MCMAS implements OBDD-based algorithms optimised for interpreted systems and supports fairness, counter-example generation, and interactive execution (both in explicit and symbolic mode). MCMAS has been used in a variety of scenarios including web-services, diagnosis, and security. MCMAS is released under GNU-GPL. Multi-Agent Systems FormalismsMulti-Agent Systems (MAS) formalisms are typically built on extensions of computational tree logic (CTL). For the purposes of this abstract we consider specifications given in the following language L built from a set of propositional atoms p ∈ P , and a set of agents i ∈ A (G ⊆ A denotes a set of agents):⋆

We present MCMAS, a model checker for the verification of multi-agent systems. MCMAS supports efficient symbolic techniques for the verification of multi-agent systems against specifications representing temporal, epistemic and strategic properties. We present the underlying semantics of the specification language supported and the algorithms implemented in MCMAS, including its fairness and counterexample generation features. We provide a detailed description of the implementation. We illustrate its use by discussing a number of examples and evaluate its performance by comparing it against other model checkers for multi-agent systems on a common case study.

We present a methodology for the verification of multi-agent systems, whose properties are specified by means of a modal logic that includes a temporal, an epistemic, and a modal operator to reason about correct behaviour of agents. The verification technique relies on model checking via ordered binary decision diagrams. We present an implementation and report on experimental results for two scenarios: the bit transmission problem with faults and the protocol of the dining cryptographers.

No abstract

No abstract