Specification and Proof of Liveness Properties in B Event Systems

International audienceIn this paper, we give a framework for defining an extension to the event B method. The event B method allows us to state only invariance properties, but in some applications such as automated or distributed systems, fairness and eventuality properties must also be considered. We first extend the expressiveness of the event B method to deal with the specification of these properties. Then, we give a semantics of this extended syntax over traces, in the same spirit as the temporal logic of actions TLA does. Finally, we give verification rules of these properties. We denote by temporal B model, the B model extended with liveness properties. We illustrate our method on a case study related to automated system