Gossip-Based Ad Hoc Routing

Abstract

Many ad hoc routing protocols are based on(some variant of) flooding. Despite various optimizations, many routing messages are propagated unnecessarily. We propose a gossiping-based approach to reduce the overhead of the routing protocols. In large networks, Gossiping exhibits bimodal behavior in sufficiently large networks: in some executions, the gossip dies out quickly and hardly any node gets the message; in the remaining executions, a substantial fraction of the nodes gets the message. The fraction of executions in which most nodes gets the message depends on the gossiping probability and the topology of the network. In the networks we have considered, using gossiping probability between 0.6 and 0.8 suffices to ensure that almost every node gets the message in almost every execution. For large networks, this simple gossiping protocol uses up to 35% fewer messages than flooding, with improved performance. Gossiping can also be combined with various optimizations of flooding to yield further benefits. Simulations show that adding gossiping to AODV results in significant performance improvement, even in networks as small as 150 nodes only. We expect that the improvement should be even more significant in larger networks.