1,151 research outputs found
Congruence from the Operator's Point of View: Compositionality Requirements on Process Semantics
One of the basic sanity properties of a behavioural semantics is that it
constitutes a congruence with respect to standard process operators. This issue
has been traditionally addressed by the development of rule formats for
transition system specifications that define process algebras. In this paper we
suggest a novel, orthogonal approach. Namely, we focus on a number of process
operators, and for each of them attempt to find the widest possible class of
congruences. To this end, we impose restrictions on sublanguages of
Hennessy-Milner logic, so that a semantics whose modal characterization
satisfies a given criterion is guaranteed to be a congruence with respect to
the operator in question. We investigate action prefix, alternative
composition, two restriction operators, and parallel composition.Comment: In Proceedings SOS 2010, arXiv:1008.190
Split-2 Bisimilarity has a Finite Axiomatization over CCS with<br> Hennessy's Merge
This note shows that split-2 bisimulation equivalence (also known as timed
equivalence) affords a finite equational axiomatization over the process
algebra obtained by adding an auxiliary operation proposed by Hennessy in 1981
to the recursion, relabelling and restriction free fragment of Milner's
Calculus of Communicating Systems. Thus the addition of a single binary
operation, viz. Hennessy's merge, is sufficient for the finite equational
axiomatization of parallel composition modulo this non-interleaving
equivalence. This result is in sharp contrast to a theorem previously obtained
by the same authors to the effect that the same language is not finitely based
modulo bisimulation equivalence
- …