Fault diagnosis in a wireless network

Given a wireless network and a graph modelling the node connection topology, we address the problem of fault diagnosis of nodes. When the external point of access to network information is at a lower layer of the ISO/OSI protocol stack, the problem is trivial. However, as often occurs, a user is able to access the network at the application layer : this implies that the available observation of the network status is considerably restricted, and solving the diagnosis problem is not trivial. In this paper, we state necessary and sufficient conditions for being able to detect which node is faulty, and propose a diagnosis algorithm on the basis of diagnosability definitions and theoretical studies developed for timed and hybrid automata in the computer science community.