Efficient Contextual Unfolding

  • César Rodríguez
  • Stefan Schwoon
  • Paolo Baldan
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6901)


A contextual net is a Petri net extended with read arcs, which allow transitions to check for tokens without consuming them. Contextual nets allow for better modelling of concurrent read access than Petri nets, and their unfoldings can be exponentially more compact than those of a corresponding Petri net. A constructive but abstract procedure for generating those unfoldings was proposed in earlier work; however, no concrete implementation existed. Here, we close this gap providing two concrete methods for computing contextual unfoldings, with a view to efficiency. We report on experiments carried out on a number of benchmarks. These show that not only are contextual unfoldings more compact than Petri net unfoldings, but they can be computed with the same or better efficiency, in particular with respect to the place-replication encoding of contextual nets into Petri nets.


Enrich Condition Compound Condition Enrich Event Asynchronous Circuit Reachable Marking 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  • César Rodríguez
    • 1
  • Stefan Schwoon
    • 1
  • Paolo Baldan
    • 2
  1. 1.LSV, ENS Cachan & CNRS, INRIA SaclayFrance
  2. 2.Dipartimento di Matematica Pura e ApplicataUniversità di PadovaItaly

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