# Robust Evolutionary-Game-Based Routing for Wireless Multimedia Sensor Networks
## 5 Performance Evaluation
### Simulation Results and Discussions
Furthermore, once the priority-based forwarding list is established in QMOR, the delay decreases. EGR performs better than both LEACH-C and QMOR. Also, the data volume to be delivered is reduced in EGR due to Algorithm 1, achieving lesser delay. The biggest advantage of EGR over QMOR is the reduced number of hops. EGR's clustering architecture allowed only two hop transmissions to the closest possible sink node whereas QMOR being an opportunistic routing protocol has to undergo  
Figure 16: Number of living nodes showing network lifetime. through multiple hops many times incurring higher delay. EGR is implemented in a scenario where nodes are involved in a moving object tracking. As time passes by, the movement of the object is increased so that the nodes could have frequent FoVs of the object. The goal behind this is to check how the data redundancy avoidance algorithm facilitates EGR with the lessened amount of multimedia data. Since GEEC and EEERE do not have any redundant data avoidance mechanism, they has to deal with higher data volume compared to EGR. Therefore, EGR has lesser end-to-end delay. Lastly, even though AB routing had a data redundancy avoidance mechanism, EGR shows better performance because of the multiple sink nodes. As shown in Figure 17, we can see that EGR performs better and shows less amount of delay than other five protocols. In summary, the use of multiple sink nodes, direct one hop transmission from the CHs to the closest sink nodes, and data redundancy avoidance mechanism are the main reasons for the performance improvement. Average end-to-end delay versus the network load: Normally, WMSNs have to deal with high volume of multimedia data. To prove the feasibility of the proposed EGR, the end-to-end delay and network load were comparatively observed along with different simulation time, as shown in Figure 18. As time increases, both end-to-end delay and network load are increased. Figure 17: Average end-to-end delay vs. the number of nodes. Figure 18: _Cont._  
In Figure 18a-c, average end-to-end delay is calculated almost in every 90 s during the whole simulation time. By observing the figures, it can be seen that EGR took 1.2 s to transmit 1.8 megabyte (MB) of data. On the other hand, QMOR, AB routing, LEACH-C, GEEC, and EEREG take the same amount of time to transmit 1.3 MB, 0.612 MB, 0.583, 0.6 MB, and 0.9 MB of data, respectively. This is mainly because of the shorter distance between the CH nodes and sink nodes in the network. Packet delivery ratio: For this routing metric, we considered transmissions of the CHs to the sink node/s. To calculate the average packet delivery ratio, we first summed the number of data packets transmitted by each CH. Assuming that there are \(N\) number of clusters in the network, we determined the average number of packets transmitted using the following equation:  
\[Tx_{\text{arg}}=\frac{\sum_{i=1}^{N}DT_{CH_{i}}}{N}, \tag{18}\]  
where \(Tx_{\text{arg}}\) is the average number of packets transmitted to the sink node and \(DT_{CH_{i}}\) is the data packets transmitted by any CH in the network. Finally, the average packet delivery ratio is calculated using Equation (19):  
Figure 18: Average end-to-end delay vs. network load: (**a**) EGR; (**b**) AB routing; (**c**) QMOR; (**d**) LEACH-C; (**e**) GEEC; (**f**) EEREG. \[PDR_{avg}=\frac{Tx_{avg}}{Rx_{sink}}, \tag{19}\]  
where, \(PDR_{avg}\) is the average packet delivery ratio, \(Rx_{sink}\) is the data received by the sink node. Since there are multiple sinks in EGR, Equation (18) is not applicable for it. The \(PDR_{avg}\) for EGR is calculated as;  
Figure 15:0  
where, \(Rx_{sink1},Rx_{sink2}\), and \(Rx_{sink3}\) are the data received by the three sink nodes used in EGR. QMOR is an opportunistic routing protocol. Moreover, EGR, AB routing, and LEACH-C are cluster-based routing protocols. It is not feasible to compare an opportunistic routing protocol with cluster-based routing protocols because the packet delivery ratio will always be high for opportunistic routing.