Node caching enhancement of reactive ad hoc routing protocols [MANET]

Enhancing route request broadcasting protocols constitutes a substantial part of recent research in mobile ad hoc network (MANET) routing. In this paper, we introduce a novel node caching approach for constraining the route request protocol in ad hoc routing. We have implemented node caching enhancement AODV-NC of AODV which improves the original AODV in all three metrics - extensive simulations in NS-2 show average decrease by 90% in communication overhead as well as average decrease by 63% in the delay, and average increase by 20% in the delivery ratio. We have also proposed a new measure of fairness of ad hoc routing protocols which depends on distribution of the forwarding load among nodes. The AODV-NC protocols are shown to be unfair and make certain overused nodes exhaust their batteries prematurely. We also suggest a load-balancing scheme that improves fairness and lifetime of AODV-NC, sustaining considerable improvement in overhead, delivery ratio and delay over the standard AODV.