A π-calculus with explicit substitutions: The late semantics

Abstract

A new formulation of the π-calculus, where name instantiation is handled explicitly, is presented. The explicit handling of name instantiation allows us to reduce the π-calculus transitional semantics to a standard SOS framework. Hence, π-calculus bisimulation models can take fully advantage of the SOS metatheory developed for ‘static’ process calculi. For instance, complete axiomatic characterizations of π-calculus bisimulation equivalences can be automatically derived by turning SOS rules into equations. Moreover, this formulation of the π-calculus is promising for the development of semantic-based automatic verification tools. Here we treat in full detail the Late bisimulation semantics. A finite branching labelled transition system and a complete axiomatic characterization of the Late bisimulation equivalence are obtained.