Time-Bounded Reachability in Distributed Input/Output Interactive Probabilistic Chains

Abstract. We develop an algorithm to compute timed reachability pro-babilities for distributed models which are both probabilistic and non-deterministic. To obtain realistic results we consider the recently intro-duced class of (strongly) distributed schedulers, for which no analysis techniques are known. Our algorithm is based on reformulating the nondeterministic models as parametric ones, by interpreting scheduler decisions as parameters. We then apply the PARAM tool to extract the reachability probability as a polynomial function, which we optimize using nonlinear programming