Formal Methods in System Design

, Volume 6, Issue 1, pp 45–65 | Cite as

A technique of state space search based on unfolding

  • K. L. McMillan
  • D. K. Probst


Unfoldings of Petri nets provide a method of searching the state space of concurrent systems without considering all possible interleavings of concurrent events. A procedure is given for constructing the unfolding of a Petri net, terminating the construction when it is sufficient to represent all reachable markings. This procedure is applied to hazard and deadlock detection in asynchronous circuits. Examples are given of scalable systems with exponential size state spaces, but polynomial size unfoldings, including a distributed mutual exclusion ring circuit.


verification Petri nets unfolding hazard detection deadlock detection mutual exclusion partial orders state explosion problem 


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Copyright information

© Kluwer Academic Publishers 1995

Authors and Affiliations

  • K. L. McMillan
  • D. K. Probst

There are no affiliations available

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