Permutable agents in process algebras

  • FranÇois Michel
  • Pierre Azéma
  • FranÇois Vernadat
Regular Sessions Session 6: Models and Methods
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1055)


Within the framework of symmetrical systems, an extension of CCS [6], so-called PCCS, is described. PCCS equips CCS with the concept of pool of agents by means of the explicit structure of Pool expressions. The symmetries whithin a Pools of agents may then be used to simplify the validation process of concurrent systems.

An equivalence relation, so-called Permutability, is formally introduced: two PCCS expressions are permutable iff they can be obtained from each other by a permutation of expressions within a pool. Permutability can be decided in a polynomial time w.r.t. the length of expressions. The Permutability notion allows the definition of symbolic Processes, which describe the system behaviour when inside a pool the agent identities are removed. A transitional semantics is defined and behavioral verifications may be conducted over symbolic Processes.

Key words

Process Algebras Symmetries Concurrent Systems Verification 


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Copyright information

© Springer-Verlag Berlin Heidelberg 1996

Authors and Affiliations

  • FranÇois Michel
    • 1
  • Pierre Azéma
    • 1
  • FranÇois Vernadat
    • 1
  1. 1.LAAS/CNRS 7Toulouse CedexFrance

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