## 6 Performance Evaluations
### Simulation Results
#### 6.3.2 Miss Ratio Deadline Evaluation  
In this series of experiments, the performance of the proposed method is assessed in terms of the deadline miss ratio in comparison to SMRP [15] and EERP [23] for the above-mentioned scenarios under different traffic rates, a different number of sink nodes, and different deadline values.  
1. _Deadline miss ratio evaluation under the first scenario_  
This set of experiments examines the variation of deadline miss ratio with average traffic rate, sink node number, and deadline value under the first scenario.  
First experiment examines how the deadline miss ratio varies with the average traffic rate. To evaluate this variation, the simulation experiment increases the average traffic rate from three to 11 packets per second while keeping the sink nodes and deadline at three and 700 ms. Figure 6 compares deadline miss ratios with various traffic rates. As shown in the figure, the proposed routing method produced a lower deadline miss ratio than that of the SMRP and EERP algorithms. The proposed algorithm changes the target packet speed at each hop and picks relay nodes that can deliver the data on time. The relaying speed is then considered while picking the next forwarder. Moreover, it evaluates link quality to reduce retransmission latency. Such parameters reduce the packet miss ratio.  
In the case of the SMRP and EERP routing algorithms, the real-time delivery of data is not considered; therefore, the bounded delay requirements are not satisfied. Additionally, the packets in such algorithms cannot avoid unreliable paths, which causes a lot of lost packets and thus increases the delivery delay due to packet retransmission. Hence, this increases the deadline miss ratio.  
The primary purpose of the second simulation experiment is to analyze the deadline miss ratio with the number of sink nodes under the first scenario. The simulation experiment is launched to examine this variance by varying the number of sink nodes from one to three nodes while fixing the deadline and average traffic rate at 700 ms and three packets per second, respectively. Figure 7 shows the variation of the deadline miss ratio with  
Figure 6: Influence of increasing average traffic rate on deadline miss ratio under the first scenario.  
respect to a different number of sink nodes. As shown in the figure, the deadline miss ratio decreases with the increasing number of sink nodes. Actually, with deploying more sink nodes in the network, the data packets have to take a shorter distance to reach sink nodes, which improves the delivery latency, and thus the deadline miss ratio will be decreased. However, the figure demonstrates that the suggested method increases the number of sink nodes while delivering the lowest deadline miss ratio among the available solutions. This is because it integrated the relaying speed and link quality in making routing decisions, which decreases the delivery delay and, thus, the deadline miss ratio. On the other hand, the SMRP and EERP routing algorithms have to take longer delivery delays as they do not consider the real-time delivery of data and reliability of data transmission.  
The third simulation experiment evaluates how the deadline miss ratio increases under the first scenario. This experiment adjusts the deadline from 700 to 1000 ms, but the number of sink nodes and average traffic rate is kept the same. Figure 8 shows deadline miss ratios. Figure 8 shows that missed deadlines decrease as deadlines become extended. Packets take longer to reach sink nodes as deadlines increase. It speeds up the delivery of packets to the sink node. The proposed algorithm achieves the lowest deadline-miss ratio by selecting relay nodes that can transmit real-time data packets on time. Link quality is also considered, which lowers delivery delay due to retransmission. SMRP and EERP cannot offer timely messaging services. They do not address how to prevent unreliable wireless networks, which affects delivery delays because of missed packet retransmission.