Impact of Node Speed and Transmission Range on the Hello Interval of MANET Routing Protocols

In mobile ad-hoc networks (MANETs), nodes use hello messages to detect neighbor nodes and to maintain link connectivity. In a typical MANET routing, a node broadcasts hello messages at a fixed interval. However, a fixed hello interval causes a long delay of neighbor discovery (too long hello intervals) or a more bandwidth waste by unnecessary protocol overhead (too short hello intervals). In this paper, we investigate the impact of node speed and transmission range on hello intervals in terms of network throughput. Through simulations for a mobile ad-hoc network using AODV routing protocol, we show that the hello interval to maximize the network throughput can be determined as a function of node speed and transmission range.