## 4 Simulation Results
\begin{table}
\begin{tabular}{p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt}} \hline \hline
**Protocol** & **Cooperation** & **Sink Nodes** & **Depth Threshold** & **Nodes Selection Parameters** \\ \hline LFEER & Not involved. & Placed at the top of the water and static. & Fixed. & Residual energy, A Number of hops, Bit error rate. \\ \hline Co-LFEER & Involved with one relay node. & Placed at the top of the water surface and static. & Fixed. & Residual energy, A Number of hops, Bit error rate. \\ \hline Co-DBR & Involved with two relay nodes. & Static and placed at upper surface of the water. & Fixed. & Depth. \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Protocols Information. nodes than the Co-DBR protocol, because in Co-LFEER protocol only one RLN and the DSN contribute to transmit the information bags toward the targeted nodes. In the Co-DBR protocol, two forwarder nodes and the DSN transmit the information bag towards the final DNN, which consumes more energy and thus results in fewer alive nodes. The numbers of dead node is lower in count in the proposed LFEER and Co-LFEER protocols than Co-DBR, as shown in Figure 7. The LFEER protocol has the least count of dead nodes than the Co-DBR and the Co-LFEER due to the absence of cooperation and by selecting the only one DSN in the information bags transmission towards the final DNN. The Co-LFEER has cooperation by considering a single RLN and the Co-DBR involves cooperation with the two relay nodes in data bags transmission. Thus, the Co-LFEER protocol consumes less energy and has fewer dead nodes than the Co-DBR. The number of dead nodes at the end of 500 rounds identifies that the death rate of the nodes in the Co-DBR protocol is the maximum. After 500 rounds, in Co-DBR there are 175 dead node, in the LFEER there are 145 dead nodes and in the Co-LFEER there are 165 dead nodes. Figure 6: Alive nodes. Figure 7: Dead nodes. Figure 8 represents the comparative results of packets delivery ratio. In the proposed LFEER protocol, no cooperation is included, which minimizes the PDR as compared to the Co-LFEER and the Co-DBR protocols. The proposed Co-LFEER protocol has the maximum PDR because, in the Co-LFEER protocol, cooperation involves RLN with the minimum bit error rates. By doing this, packet drop and path loss effect decrease and correspondingly packets delivery ratio increases. On the other hand, the Co-DBR protocol has not involved BER in selection criteria for the destination and relay nodes which degrades the PDR. Figure 8 shows that, from round 0 to round 150, the PDR of the proposed Co-LFEER and the Co-DBR protocols is the same because, initially, every protocol uses its best nodes in data advancement. Later, death of such nodes and intelligent selection of nodes to mitigate channel effects in the Co-LFEER makes its PDR the highest. The delay is exhibited in Figure 9. The proposed LFEER protocol has the smallest delay due to the absence of cooperation in data packets transmission. From round 0 to round 180, the proposed Co-LFEER protocol has less delay than the Co-DBR as nodes providing low delay are alive in the latter. Such nodes die later, after 180 rounds, making delay in Co-LFEER higher. In summary, the LFEER protocol provides efficient consumption of power of nodes and considers channel impairments in the form of fitness criterion of the nodes that route packets. This feature is lacking in the Co-DBR and other protocols described above. Rather, channel impairments are dealt with at the cost of high energy consumption in these protocols. On the other hand, the Co-LFEER protocol combines channel impairments with cooperative routing and is independent of the localization of nodes. The Co-DBR blindly selects nodes during cooperation without considering channel impairments. In addition, other related protocols described above either do not consider channel impairments or require localization of nodes. These feature compromise throughput, which Co-LFEER avoids. Figure 8: Total packets delivery ratio.