EEIRA: An Energy Efficient Interference and Route Aware Protocol for Underwater WSNs

In this paper, an energy efficient, interference and route aware (EEIRA) protocol is proposed for underwater wireless sensor networks (UWSNs). The protocol combines the direct and relay forwarding mechanisms in transmitting the packets from source to destination. The relaying process involves selection of the best relay from a set of relay nodes. A relay node having the least distance from source to destination and the minimum number of neighbor nodes qualifies the criterion of the best relay. The direct transmission is used when the best relay is not within the transmission range of the source node. From top to bottom, the network is divided into three different zones, destination, relay and source zone, respectively. The relay zone has the greatest area to have maximum choices of selecting the best relay from the relay nodes residing in it. Nodes in all the three regions can sense the attribute and send the data to the sink. The destination nodes send data directly to sink. The relay nodes send the packets to the sink either directly or through the relaying process. The source nodes in the bottom send the data to sink via the best relay node or directly. Based on simulation results, the proposed protocol outperforms the depth based routing (DBR) scheme in terms of energy efficiency by selecting the best relay, reducing number of hops and following the shortest path to reduce channel losses.