Investigating the Impact of Adaptive Beaconing on GEOADV Performance

Routing in VANETs is challenging due to the high mobility and dynamic topology. Geographic routing is considered suitable for such networks. In geographic routing, nodes are able to maintain up-to-date information on their neighbors by using beaconing. Beaconing is successful in VANET environments but causes a large amount of routing overhead. This paper investigates the impact adaptive beaconing has on the Geographic Ad hoc On-Demand Distance Vector (GEOADV) protocol. In our adaptive beaconing scheme, each vehicle starts with the same initial broadcast interval. After the first broadcast, the next beacon interval is then determined by supplying the fuzzy inference engine with three inputs. These inputs are the number of neighbors in a one-hop distance, the speed of the vehicles, and the link quality of the network. GEOADV performance is evaluated with an adaptive beacon rate network and compared to its performance in three different fixed beacon rates networks. We are able to show that the adaptive beaconing scheme is able to reduce routing overhead, increases the average delivery ratio, and decreases the average delay. We are also able to show that by reducing beacon frequency the information accuracy is degraded and packets which are forwarded are less suitable or get dropped due to the route becoming stale.