PRISM is a probabilistic model checker, a formal verification software tool for the modelling and analysis of systems that exhibit probabilistic behaviour [1][2]. One source of such systems is the use of randomization, for example in communication protocols like Bluetooth and FireWire, or in security protocols such as Crowds and Onion routing. Stochastic behaviour also arises in many other computer systems, for example due to equipment failures or unpredictable communication delays. Yet another class of systems amenable to this kind of analysis are biochemical reaction networks.
PRISM was initially developed at the University of Birmingham and is now based at the Oxford University Computing Laboratory. It is open-source software, released under the GNU General Public License.