Network–wide broadcasting is used extensively in mobile ad hoc networks for route discovery and for disseminating data throughout the network. Flooding is a common approach to performing network-wide broadcasting. Although it is a simple mechanism that can achieve high delivery ratio, flooding consumes much of the communication bandwidth and causes serious packet redundancy, contention and collision. In this paper, the authors propose new broadcast schemes that reduce the overhead associated with flooding. In these schemes, a node selects a subset of its neighbors for forwarding the packet being broadcast to additional nodes. The selection process has for goal reducing the number of neighbors and maximizing the number of nodes that they can reach (i.e., forward the packet to). By applying this novel neighborhood-based broadcasting strategy, the authors have come up with routing protocols that have very low overhead. These protocols were implemented and simulated within the GloMoSim 2.03 network simulator. The simulation experiments show that our routing protocols can reduce the overhead for both low and high mobility substantially, as compared with the well-known and promising AODV routing protocol. In addition, they outperform AODV by increasing the delivery ratio and decreasing the end-to-end delays of data packets.
Route discovery optimization of reactive routing protocols for mobile ad hoc networks
