Channel quality based Adaptive Gossip Flooding mechanism for AODV

This On-demand route discovery mechanism of reactive protocols based on flooding of route request packets faced serious excursion of “broadcast storm”. Moreover, frequent path breakages are experienced due to link failures, as an impact of time varying characteristics of radio channel and/or node mobility. In this paper Channel Quality Adaptive Gossip Flooding mechanism for Ad hoc On-demand Distance Vector (AODV) routing protocol, named CQAG-AODV is proposed as a solution to these issues. CQAG-AODV is a cross layer approach, where in route discovery mechanism of AODV is tuned to signal quality of wireless channel. Flooding of route requests (RREQs) is controlled with probabilistic measures based on signal strength observed at the physical layer. Proposed scheme tries to discover robust paths by forwarding more RREQs along good signal quality links rather than on weaker ones. The proposed scheme is implemented using Qualnet simulator and performance is evaluated in terms of PDR, throughput, end to end delay and link breakage. Simulation results show that CQAG-AODV significantly curtails the link breakages with reduced RREQ forwarding overhead compared to conventional AODV and thus takes care of “broadcast storm” problem.