A distributed fault identification protocol for wireless and mobile ad hoc networks

Abstract

This paper considers the problem of self-diagnosis of wireless and mobile ad hoc networks (MANETs) using the comparison approach. In this approach, a network (MANET) consists of a collection of n independent heterogeneous mobile or stationary hosts interconnected via wireless links, and it is assumed that at most of these hosts are faulty. In order to diagnose the state of the MANET, tasks are assigned to pairs of hosts and the outcomes of these tasks are compared. The agreements and disagreements between the hosts are the basis for identifying the faulty ones. The comparison approach is believed to be one of the most practical fault identification approaches for diagnosing hard and soft faults. We develop a new distributed self-diagnosis protocol, called Dynamic-DSDP, for MANETs that identifies both hard and soft faults in a finite amount of time. The protocol is constructed on top of a reliable multi-hop architecture. Correctness and complexity proofs are provided and they show that our Dynamic-DSDP performs better, from a communication complexity viewpoint, than the existing protocols. We have also developed a simulator, that is scalable to a large number of nodes. Using the simulator, we carried out a simulation study to analyze the effectiveness of the self-diagnosis protocol and its performance with regards to the number of faulty hosts. The simulation results show that the proposed approach is an attractive and viable alternative or addition to present fault diagnosis techniques in MANET environments.