Model checking of real-time reachability properties using abstractions

  • Conrado Daws
  • Stavros Tripakis
Regular Sessions Verification of Real-Time Systems
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1384)


Practical real-time model checking suffers from the stateexplosion problem: the size of the state space grows exponentially with many system parameters: number of clocks, size of constants, number of system components. To cope with state explosion, we propose to use abstractions reducing the state-space while preserving reachability properties. Four exact, plus one safe abstractions are defined. In the main abstraction (simulation) a concrete state is mapped to a symbolic abstract state (a set of concrete states). The other four abstractions are defined on top of the simulation one. They can be computed on-the-fly in a completely orthogonal manner and thus can be combined to yield better reductions. A prototype implementation in the tool Kronos has permitted to verify two benchmark examples with a significant scale-up in size.


Model Check Binary Decision Diagram Symbolic State Concrete State Time 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 1998

Authors and Affiliations

  • Conrado Daws
    • 1
  • Stavros Tripakis
    • 1
  1. 1.VerimagCentre équationGièresFrance

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