Abstract:
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.
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