Quasi-Equal Clock Reduction: More Networks, More Queries

  • Christian Herrera
  • Bernd Westphal
  • Andreas Podelski
Part of the Lecture Notes in Computer Science book series (LNCS, volume 8413)

Abstract

Quasi-equal clock reduction for networks of timed automata replaces equivalence classes of clocks which are equal except for unstable phases, i.e., points in time where these clocks differ on their valuation, by a single representative clock. An existing approach yields significant reductions of the overall verification time but is limited to so-called well-formed networks and local queries, i.e., queries which refer to a single timed automaton only. In this work we present two new transformations. The first, for networks of timed automata, summarises unstable phases without losing information under weaker well-formedness assumptions than needed by the existing approach. The second, for queries, now supports the full query language of Uppaal. We demonstrate that the cost of verifying non-local properties is much lower in transformed networks than in their original counterparts with quasi-equal clocks.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  • Christian Herrera
    • 1
  • Bernd Westphal
    • 1
  • Andreas Podelski
    • 1
  1. 1.Albert-Ludwigs-Universität FreiburgFreiburgGermany

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