Reliable and Delay Aware Routing Protocol for Underwater Wireless Sensor Networks

The reliability of Underwater Wireless Sensor Networks (UWSNs) is measured in terms of energy consumption (EC), end-to-end delay(E2E), and packet delivery ratio (PDR). The adverse effects of a channel may cause data loss. Reducing delay up to the possible extent improves the reliability of the network, also increasing the number of nodes in a particular network increases reliability. Besides, increasing the number of nodes improves reliability but also increases power consumption. In order to overcome these shortcomings, the two routing protocols are proposed in this paper, namely the Delay and Reliability Aware Routing (DRAR) protocol and the Cooperative Delay and Reliability Aware Routing (Co-DRAR) protocol for UWSNs. In the DRAR protocol, the network is divided into two equal regions where two sink nodes(SNs) are positioned at the upper region of the network and two SNs are placed at the mid-region of the network. The protocol chooses the relay node based on residual energy (RE), distance, and Bit Error Rate (BER). These parameters protect the data packets from corruption and also provide a stable path (where nodes remain active for longer periods and do not die quickly). The protocol uses a single link and may get worse sometimes while changing channel circumstances. To address this problem, a cooperative routing scheme is added to the DRAR protocol in order to develop its enhanced version known as the Co-DRAR protocol. The protocol works by allowing the destination to receive multiple copies of data packets in order to decide the quality of packets. The proposed protocols DRAR and Co-DRAR perform routing irrespective of the geographical position of sensor nodes conversely to some conventional routing protocols. This is why our proposed protocols perform better than the well-known protocol i.e. Depth base routing (DBR) in terms of EC, E2E, PDR, dead nodes, packet drop ratio, and number of alive nodes.