The Coarsest Congruence for Timed Automata with Deadlines Contained in Bisimulation

  • Pedro R. D’Argenio
  • Biniam Gebremichael
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3653)


Delaying the synchronization of actions may reveal some hidden behavior that would not happen if the synchronization met the specified deadlines. This precise phenomenon makes bisimulation fail to be a congruence for the parallel composition of timed automata with deadlines, a variant of timed automata where time progress is controlled by deadlines imposed on each transition. This problem has been known and unsolved for several years. In this paper we give a characterization of the coarsest congruence that is included in the bisimulation relation. In addition, a symbolic characterization of such relation is provided and shown to be decidable. We also discuss the pitfalls of existing parallel compositions in this setting and argue that our definition is both reasonable and sufficiently expressive as to consider the modeling of both soft and hard real-time constraints.


Parallel Composition Process Algebra Time Progress Time Automaton Small Relation 
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 2005

Authors and Affiliations

  • Pedro R. D’Argenio
    • 1
  • Biniam Gebremichael
    • 2
  1. 1.CONICET – FaMAFUniversidad Nacional de Córdoba, Ciudad UniversitariaCórdobaArgentina
  2. 2.Institute for Computing and Information SciencesRadboud University NijmegenNijmegenThe Netherlands

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