Section: New Results

Timed, Probabilistic, and Stochastic Extensions

In the context of the SENSATION project (see § 8.3.1.1), we study the specification and verification of quantitative properties of concurrent systems, which requires expressive and user-friendly property languages combining temporal, data-handling, and quantitative aspects.

In 2016, in collaboration with José Ignacio Requeno (Univ. Zaragoza, Spain), we aimed at facilitating the quantitative analysis of systems modeled as PTSs (Probabilistic Transition Systems) labeled by actions containing data values and probabilities. We proposed a new regular probabilistic operator that computes the probability measure of a path specified by a generalized regular formula involving arbitrary computations on data values. This operator, which subsumes the Until operators of PCTL (Probabilistic Computation Tree Logic)  [41] and their action-based counterparts, can provide useful quantitative information about paths having certain (e.g., peak) cost values. We integrated the regular probabilistic operator into MCL and we devised an associated on-the-fly model checking method, based on a combined local resolution of linear and Boolean equation systems. We implemented the method in a prototype extension of the EVALUATOR model checker and experimented it on realistic PTSs modeling concurrent systems. This work led to a publication [22].