Playing with Probabilities in Reconfigurable Broadcast Networks

We study verification problems for a model of network with the following characteristics: the number of entities is parametric, communication is performed through broadcast with adjacent neighbors, entities can change their internal state probabilistically and reconfiguration of the communication topology can happen at any time. The semantics of such a model is given in term of an infinite state system with both non deterministic and probabilistic choices. We are interested in qualitative problems like whether there exists an initial topology and a resolution of the non determinism such that a configuration exhibiting an error state is almost surely reached. We show that all the qualitative reachability problems are decidable and some proofs are based on solving a 2 player game played on the graphs of a reconfigurable network with broadcast with parity and safety objectives.