Acta Informatica

, Volume 46, Issue 3, pp 169–191 | Cite as

Hardness of equivalence checking for composed finite-state systems

  • Zdeněk Sawa
  • Petr Jančar
Original Article


Computational complexity of comparing behaviours of systems composed from interacting finite-state components is considered. The main result shows that the respective problems are EXPTIME-hard for all relations between bisimulation equivalence and trace preorder, as conjectured by Rabinovich (Inf Comput 139(2):111–129, 1997). The result is proved for a specific model of parallel compositions where the components synchronize on shared actions but it can be easily extended to other similar models,   to labelled 1-safe Petri nets. Further hardness results are shown for special cases of acyclic systems.


Global State Equivalence Check Parallel Composition Winning Strategy Label Transition System 
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 2009

Authors and Affiliations

  1. 1.FEITechnical University of OstravaOstrava-PorubaCzech Republic

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