| Abstract: | LOTOS is a formal specification language for concurrent and distributed systems. Basic LOTOS is the version of LOTOS without value‐passing. A widely used approach to the verification of temporal properties is model checking. Often, in this approach the formal specification is translated into a labeled transition system on which formulae expressing properties are checked. A problem with this verification technique is state explosion: concurrent systems are often represented by automata with a prohibitive number of states. In this paper we show how, given a set ρ of actions, it is possible to automatically obtain for a Basic LOTOS program a reduced transition system to which only the arcs labeled by actions in ρ belong. The set ρ of actions plays a fundamental role in conjunction with a temporal logic defined by the authors in a previous paper: selective mu‐calculus. The reduced system with respect to ρ preserves the truth value of all selective mu‐calculus formulae with actions from the set ρ. We act at both syntactic and semantic levels. From a syntactic point of view, we define a set of transformation rules obtaining a smaller program. On the semantic side, we define a non‐standard semantics which dynamically reduces the transition system during generation. We present a tool implementing both the syntactic and the semantic reduction. Copyright © 1999 John Wiley & Sons, Ltd. |
