An Efficient Restricted Flooding Based Route Discovery (RFBRD) Scheme for AODV Routing

– AODV is one of the widely used routing schemes in WSN and MANET due to its on-demand characteristics and low overhead. The excessive flooding at the time of route discovery consumes lots of node energy. The network performance deteriorates due to the unconstrained and blind flooding of route request (RREQ) packets. The excessive flooding mechanism accounts for multiple reception of RREQ packets at nodes. It causes unwanted path loops, and packet collisions thus exhausting the node batteries. The restricted flooding-based route discovery (RFBRD) mechanism introduced in this paper adopts two different strategies for receiving first and subsequent RREQ packets before they are forwarded. On reception of the first RREQ at an intermediate node, the RREQ is forwarded/restricted based on node densities evaluated for the neighbourhood as well as the network. Four regions and five probabilities are considered based on node densities in the neighbourhood and the network. The mobile nodes lying in the low-density region are allowed to transmit the RREQ packets with higher probability as compared to other nodes present in high-density regions when the RREQ is received for the first time. For subsequent RREQ packets at an intermediate node, the RREQ is forwarded/restricted based on energy ratios and is allowed to forward the RREQ packets, if the node has sufficient residual energy concerning neighbourhood and network energies. Simulation analysis showed enhanced and improved performance in terms of end-to-end delay, and network residual energy concerning traditional AODV.