A Conditioned Broadcasting Approach for On-Demand Ad Hoc Routing Protocols

Broadcasting is a common algorithm of on-demand ad hoc routing protocols for its simplicity and reliable accessibility. However, blind broadcasting often incurs collision, contention, and redundancy, which are called broadcast storms. As a countermeasure, we propose a conditioned broadcasting approach, by allowing each intermediate node decides whether to rebroadcast or not based on neighbourhood information when it first receives a route request (RREQ) message. The proposed scheme also takes account of node mobility speed as well as retry-times in route request process when making forwarding decisions. We demonstrate the effectiveness of the proposed scheme by applying it to Ad Hoc on-demand distance vector routing (AODV). Simulation results show that the proposed scheme outperforms original AODV in terms of several metrics, including the ratio of re-broadcasting transmitter to all mobile nodes in route discovery phase, average packet delivery ratio, and normalize routing overhead.