Event Clock Automata: From Theory to Practice

  • Gilles Geeraerts
  • Jean-François Raskin
  • Nathalie Sznajder
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6919)


Event clock automata (ECA ) are a model for timed languages that has been introduced by Alur, Fix and Henzinger as an alternative to timed automata, with better theoretical properties (for instance, ECA are determinizable while timed automata are not). In this paper, we revisit and extend the theory of ECA. We first prove that no finite time abstract language equivalence exists for ECA, thereby disproving a claim in the original work on ECA. This means in particular that regions do not form a time abstract bisimulation. Nevertheless, we show that regions can still be used to build a finite automaton recognizing the untimed language of an ECA . Then, we extend the classical notions of zones and DBMs to let them handle event clocks instead of plain clocks (as in timed automata) by introducing event zones and Event DBMs (EDBMs). We discuss algorithms to handle event zones represented as EDBMs, as well as (semi-) algorithms based on EDBMs to decide language emptiness of ECA.


Normal Form Widening Operator Clock Constraint Initial Valuation Pushdown Automaton 
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 2011

Authors and Affiliations

  • Gilles Geeraerts
    • 1
  • Jean-François Raskin
    • 1
  • Nathalie Sznajder
    • 2
  1. 1.Département d’InformatiqueUniversité Libre BruxellesBrusselsBelgium
  2. 2.UMR CNRS 7606, LIP6Université Pierre et Marie CurieParisFrance

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