Labelled transition logic: an outline

Abstract.

In the last ten years we have developed and experimented in a series of projects, including industry test cases, a method for the specification of reactive/concurrent/parallel/distributed systems both at the requirement and at the design level. We present here in outline its main technical features, providing pointers to appropriate references for more detailed presentations of single aspects, applications and documentation. The overall main feature of the method is its logical (algebraic) character, because it extends to labelled transition systems the logical/algebraic specification method of abstract data types; moreover systems are viewed as data within first-order structures called LT-structures. Some advantages of the approach are the full integration of the specification of static data and of dynamic systems, which includes by free higher-order concurrency, and the exploitation of well-explored classical techniques in many respects, including implementation and tools. On the other hand the use of labelled transition systems for modelling systems, inspired by CCS, allows us to take advantage, with appropriate extensions, of some important concepts, like communication mechanisms and observational semantics, developed in the area of concurrency around CCS, CSP and related approaches.