Symbolic Model Checking of Logics with Actions

Abstract

Abstract. Reasoning about agents and modalities such as knowledge and belief leads to models where different relations over states co-exist, or equivalently, where information (labels, actions) is associated to state transitions. This paper discusses how to augment classical CTL symbolic model-checking to support logics with actions such as A-CTL (action-CTL), and how this can be implemented using BDDs in tools such as the SMV/NuSMV package. Considering general action-state structures, we first propose a natural extension of CTL to actions, called ActionRestricted CTL (ARCTL) and adapt classical results from CTL to express model checking based on three functions eax, eau and eag. On these grounds, we present two different implementations of symbolic model checking with actions. The first approach encodes action-state models and logics into pure state-based models and logics, that can be checked with existing model-checkers. The second approach consists in a native implementation of the three extended operators. We report on our prototype implementation of both approaches based on NuSMV and give an overview of how this is used to model-check the temporal epistemic logic CTLK.

Symbolic Model Checking Commitment Protocols Using Reduction

“…The reduction from CTLC to ARCTL is then obtained by transitivity (see dash arrow in Fig.2). Before we introduce Lomuscio et al's reduction technique, we define the syntax of ARCTL using the following BNF grammar [20]:…”

“…The complete semantics of ARCTL is introduced in [20]. The reduction from a CTLK model M = (S, S 0 , T, {∼ i } i∈A , V ) to an ARCTL model M = Z, Z 0 , A, T R, V P , V A is as follows:…”

“…We present a fully-automatic verification technique of commitment protocols specified on the basis of this logic using symbolic model checking. This is done by introducing a mechanism to reduce the problem of model checking CTLC to the problem of model checking either CTLK [21], to directly use the MCMAS symbolic model checker [17], or ARCTL [20] to use the extended version of the NuSMV symbolic model checker introduced in [16]. The present paper inspires by the methodology introduced in [16] to perform the reduction.…”

Model Checking Agent Communication

“…In [30], Lomuscio et al have introduced a methodology for model checking multi-dimensional temporal-epistemic logic CTLK by extending NuSMV. The methodology is based on reducing the model checking of CTLK to the problem of model checking ARCTL, an extension of CTL with action labels and operators to reason about actions [35].…”

Experimental Evaluation of a Planning Language Suitable for Formal Verification

“…More recently, approaches applying SAT based techniques to planning in non-deterministic domains under null and partial observability have been proposed [11]. Model checking has been applied in the context of logics with actions [17] and knowledge representation [14]. The symbolic model checker of choice in this case is NuSMV.…”