Partitioning of perfect synchroneous reactive specifications to distributed processors using μ-charts

Abstract

In this contribution, it is shown that perfect synchroneous specifications can be partitioned to and implemented on a distributed processor network. To this end, we introduce a lean visual formalism, called μ-charts, that is similar to the specification language Statecharts. This formalism consists of fewer syntactic constructs than Statecharts. Further syntax like hierarchical decomposition can be derived by means of syntactic abbreviation. μ-charts' semantics is based on the assumption of perfect synchrony. This paper is one of several contributions in this context; it gives a formal background and concentrates on the question how to use perfect synchroneous, state-based description techniques as a basis for distributed implementations. The main contribution presented in this article is that the (formal and compositional) semantics of a perfect synchroneous specification is preserved when it is partitioned and implemented on distributed processors. We prove a theorem which guarantees that the communication flow between distributed parts of a perfect synchroneous specification stabilizes in a fixed point, i.e.$ terminates, independently of the processor speeds.