# A Hybrid Energy Equating Game for Energy Management in the Internet of Underwater Things
## 5 Performance Evaluation
### Data Delivery Ratio  
The packet delivery rate is directly related to the data collision and the propagation link status between the FNs and the FCHs. The multi-hop communication between FNs can increase the chances of data collision. Similarly, if the propagation link status is not good enough, then the data will not successfully deliver at the SS. Figure 8a depicts the comparison of the packet delivery ratio with the increasing number of FNs in the network among the proposed models--ADDP [20], PRADD [21], and DEEP [14]. From the graph, it is obvious that increasing the number of FNs in the network can increase the generated packets. The packet delivery ratio of the proposed framework is greater than other models because the proposed scheme does not use any greedy strategy for the forwarder selection. The nodes at optimal routes remain busy for forwarding the data of their predecessors. The multiple nodes are trying to send the data through the optimal route and drop the packet after many tries. The optimal route selection is valid up to a few hops but as the number of hops increases, there are fewer chances for a packet to be delivered successfully. The proposed model has a good delivery ratio because the next hop selection for forwarding a data packets depends upon the available, not on the optimal routes. As a result, there are very fewer chances for data packets to be dropped. Last but not least, if a node with a data packet moved into the neighboring cluster due to water currents movements, it can easily forward the data according to the assigned schedule. The FNs can adjust  
Figure 7: The comparison of average fitness and hop selection probability with time for the proposed model.  
themselves according to the water current movements, so the FNs mobility pattern cannot seriously affect its delivery ratio.  
Figure 8b depicts the comparison of the packet delivery ratio with the increasing size of the network between HEEG, ADDP [20], PRADD [21], and DEEP [14]. The packet delivery ratio of the HEEG is greater than that of the other models because its data forwarding hierarchy is consistent as it selects the congestion-free routes instead of available routes for data delivery. So, HEEG has better adjustment capacity for route selection as compared to ADDP [20], PRADD [21], and DEEP [14]. As the network size increases, the large number of nodes try to send the data through the optimal  
Figure 8: The comparison of data delivery ratio of our proposed framework with different values of number of field nodes, network size, and data generation interval.  
route; as a result, some packets may be lost after many tries. The optimal route selection is valid up to a few hops but as the number of hops increases, there are fewer chances for a packet to be delivered successfully. The CHs closer to the SS are always busy forwarding the data of their predecessors due to heavy traffic load. These CHs have the same capabilities as other FNs, so most of the data is lost here due to congestion and heavy traffic load.  
Figure 8c portrays the comparison of the packet delivery ratio with increasing the data generation interval between HEEG, ADDP [20], PRADD [21], and DEEP [14]. From Figure 8c, we can see that with an increasing data generation interval, the chances of data collision are decreased. Consequently, maximum packets are successfully delivered at the destination. ADDP has a lower packet delivery ratio because in this protocol the data cannot be conveyed to the next hop until the data packet has reached its maximum packet size. Most of the time, the packet is discarded when the maximum packet size cannot be attained within the defined time limits. In the case of PRADD and DEEP, the data relaying gateways cannot hold a packet for a long time and hand it over to the neighbors to forward it. So, data travel takes longer as compared to the average time and some time is lost due to the route mismanagement, which affects the packet delivery ratio of these protocols.