Real-time specifications

  • Alexandre David
  • Kim G. Larsen
  • Axel Legay
  • Ulrik Nyman
  • Louis-Marie Traonouez
  • Andrzej Wąsowski
Regular Paper


A specification theory combines notions of specifications and implementations with a satisfaction relation, a refinement relation, and a set of operators supporting stepwise design. We develop a specification framework for real-time systems using Timed I/O Automata as the specification formalism, with the semantics expressed in terms of Timed I/O Transition Systems. We provide constructs for refinement, consistency checking, logical and structural composition, and quotient of specifications—all indispensable ingredients of a compositional design methodology. The theory is implemented in the new tool Ecdar. We present symbolic versions of the algorithms used in Ecdar, and demonstrate the use of the tool using a small case study in compositional verification.


Real-time systems Stepwise-refinement Compositional verification Timed I/O automata 



This work was partially supported by VKR Centre of Excellence–MT-LAB, the European project COMBEST, and ARC (TP)I.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Alexandre David
    • 1
  • Kim G. Larsen
    • 1
  • Axel Legay
    • 2
  • Ulrik Nyman
    • 1
  • Louis-Marie Traonouez
    • 2
  • Andrzej Wąsowski
    • 3
  1. 1.Computer ScienceAalborg UniversityAalborgDenmark
  2. 2.INRIA/IRISARennes CedexFrance
  3. 3.IT University of CopenhagenCopenhagenDenmark

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