CCS without τ's

  • Rocco De Nicola
  • Matthew Hennessy
Session CAAP 4 Concurrency
Part of the Lecture Notes in Computer Science book series (LNCS, volume 249)


The main point of this paper is that one can develop an adequate version of CCS which does not use the special combinator τ for internal actions. Instead, the choice operator +, whose semantics is somewhat unclear, is replaced by two new choice operators ⊕ and [], representing internal and external nondeterminism respectively. The operational semantics of the resulting language is simpler and the definition of testing preorders is significantly cleaner. The essential features of the original calculus are kept; this is shown by defining a translation from CCS to the new language which preserves testing preorders.


Operational Semantic Parallel Composition Denotational Semantic Derivation Relation Choice Operator 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1987

Authors and Affiliations

  • Rocco De Nicola
    • 1
  • Matthew Hennessy
    • 2
  1. 1.Istituto di Elaborazione dell'InformazioneCNRPisa
  2. 2.Computer Science DivisionUniversity of SussexBrighton

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