Reliable and energy-efficient routing protocol for underwater acoustic sensor networks

In this paper, a reliable and energy-efficient routing (RER) protocol is proposed for underwater acoustic sensor networks to enhance the communication reliability. In the route discovery phase of the proposed method, a node with the minimum packet transmission delay to the current node is selected as its next hop node. After a route is set up, other nodes in the network will also send packets to the sink through the already established route, which greatly reduces the amount of time and energies spent to build a new route to send the packets. As a result, the real-time data will arrive at the destination earlier and the network lifetime will be extended. To handle the case of node failure on the established route, the proposed RER protocol includes a route recovery scheme that a new node will be selected instead of the failure node to continue the packet transmission. Through simulations, the proposed RER protocol is shown to outperform the traditional routing protocols in terms of average end-to-end delay, packet delivery ratio, and average energy consumption.