www.prismmodelchecker.org

PRISM-games is a new extension of PRISM for probabilistic model checking of stochastic multi-player games.

Read the tool paper or visit the website for more information.

PRISM is a probabilistic model checker, a tool for formal modelling and analysis of systems that exhibit random or probabilistic behaviour. It has been used to analyse systems from many different application domains, including communication and multimedia protocols, randomised distributed algorithms, security protocols, biological systems and many others.

Example PRISM graph PRISM can build and analyse several types of probabilistic models:

  • discrete-time Markov chains (DTMCs)
  • continuous-time Markov chains (CTMCs)
  • Markov decision processes (MDPs)
  • probabilistic automata (PAs)
  • probabilistic timed automata (PTAs)
plus extensions of these models with costs and rewards.

Models are described using the PRISM language, a simple, state-based language. PRISM provides support for automated analysis of a wide range of quantitative properties of these models, e.g. "what is the probability of a failure causing the system to shut down within 4 hours?", "what is the worst-case probability of the protocol terminating in error, over all possible initial configurations?", "what is the expected size of the message queue after 30 minutes?", or "what is the worst-case expected time taken for the algorithm to terminate?". The property specification language incorporates the temporal logics PCTL, CSL, LTL and PCTL*, as well as extensions for quantitative specifications and costs/rewards.

PRISM incorporates state-of-the art symbolic data structures and algorithms, based on BDDs (Binary Decision Diagrams) and MTBDDs (Multi-Terminal Binary Decision Diagrams) [KNP04b, Par02]. It also includes a discrete-event simulation engine, providing support for approximate/statistical model checking, and implementations of various different analysis techniques, such as quantitative abstraction refinement and symmetry reduction.

PRISM is free and open source, released under the GNU General Public License (GPL).

To cite PRISM, please use the most recent tool paper, from CAV'11:

Latest News

November 2014: Marta Kwiatkowska has been awarded an honorary doctorate from KTH Royal Institute of Technology. More details here.
August 2014: Here is a new report, published by the LMS and the Smith Institute, giving an accessible introduction to quantitative verification.
July 2014: Dave Parker will give a session on "Probabilistic real-time systems" at the MOVEP'14 summer-school on 7 July. See here for resources.
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