Bisimulations for Asynchronous Mobile Processes
Within the past few years there has been renewed interest in the study of value-passing process calculi as a consequence of the emergence of the -calculus. Here, Milner et. al have determined two variants of the notion of bisimulation, late and early bisimilarity. Most recently Sangiorgi has proposed the new notion of open bisimulation equivalence.
In this paper we consider Plain LAL, a mobile process calculus which differs from the -calculus in the sense that the communication of data values happens asynchronously. The surprising result is that in the presence of asynchrony, the open, late and early bisimulation equivalences coincide - this in contrast to the -calculus where they are distinct. The result allows us to formulate a common equational theory which is sound and complete for finite terms of Plain LAL.