Weak Sequential Composition in Process Algebras

  • Arend Rensink
  • Heike Wehrheim
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 836)


In this paper we study a special operator for sequential composition, which is defined relative to a dependency relation over the actions of a given system. The idea is that actions which are not dependent (intuitively because they share no common resources) do not have to wait for one another to proceed, even if they are composed sequentially. Such a notion has been studied before in a linear-time setting, but until recently there has been no systematic investigation in the context of process algebras.

We give a structural operational semantics for a process algebraic language containing such a sequential composition operator, which shows some interesting interplay with choice. We give a complete axiomatisation of strong bisimilarity and we show consistency of the operational semantics with an event-based denotational semantics developed recently by the second author. The axiom system allows to derive the communication closed layers law, which in the linear time setting has been shown to be a very useful instrument in correctness preserving transformations. We conclude with a couple of examples.


Operational Semantic Sequential Composition Process Algebra Denotational Semantic Complete Axiomatisation 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1994

Authors and Affiliations

  • Arend Rensink
    • 1
  • Heike Wehrheim
    • 1
  1. 1.Institut für InformatikUniversity of HildesheimHildesheimGermany

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