A Hierarchy of Behavioral Equivalences in the -calculus with Noisy Channels

Abstract

The π-calculus is a process algebra where agents interact by sending communication links to each other via noiseless communication channels. Taking into account the reality of noisy channels, an extension of the π-calculus, called the πN-calculus, has been introduced recently. This paper presents an early transitional semantics of the πN-calculus, which is not a directly translated version of the late semantics of πN, and then extends six kinds of behavioral equivalences consisting of reduction bisimilarity, barbed bisimilarity, barbed equivalence, barbed congruence, bisimilarity and full bisimilarity into the πN-calculus. Such behavioral equivalences are cast in a hierarchy, which is helpful to verify behavioral equivalence of two agents. In particular, this paper shows that due to the noisy nature of channels, the coincidence of bisimilarity and barbed equivalence, as well as the coincidence of full bisimilarity and barbed congruence, in the π-calculus does not hold in πN.