An operational framework for value-passing processes

This paper develops a semantic framework for concurrent languages with value passing. An operation analogous to substitution in the &lgr;-calculus is given, and a semantics is given for a value-passing version of Milner's Calculus of Communicating Systems (CCS). An operational equivalence is then defined and shown to coincide with Milner's (early) bisimulation equivalence. We also show how semantics maybe given for languages with asynchronous communication primitives. In contrast with existing approaches to value passing, this semantics does not reduce data exchange to pure synchronization over (potentially infinite) families of ports indexed by data, and it avoids variable renamings that are not local to processes engaged in communication.