## 4 The Proposed Method: SLP-E
### Protocol Execution Phase
#### 4.2.2 Scenario-2
Selecting the appropriate radio range in a multi-hop communication WSN involves balancing coverage, connectivity, energy efficiency, interference management, security, and other application-specific requirements [51]. Careful design and optimization of the network's physical and data link layer parameters are essential to ensure the WSN operates effectively and efficiently [52]. Since this work aims at enhancing source location privacy by introducing a new SLP protocol (named SLP-E) to prevent a passive attacker from locating the source node easily, in this study, we exclusively investigate the influence of sensor nodes' radio range on the performance parameters of SLP solutions. As it was mentioned in the previous sections of this work and in the existing SLP schemes, it is crucial to make sure that the established SLP schemes should put an emphasis on improving assets' level of privacy and lengthening the lifetime of the network. However, it is pointed out that there has been no investigation conducted to assess the potential influence of the radio range of the deployed sensor nodes on both privacy levels and the longevity of the network lifetime in the context of SLP. To understand the behavior of the proposed protocol (SLP-E) under different radio range settings, we experimented and collected additional results. In particular, the simu

\[H_{11}=\frac{\frac{2R}{3}-d}{r_{s}\times p_{r}},\]6 Network lifetime. \[H_{11}=\frac{\frac{2R}{3}-d}{r_{s}\times p_{r}},\]7 Delay. The plot for safety period vs. different values of radio range is shown in \[H_{11}=\frac{\frac{2R}{3}-d}{r_{s}\times p_{r}},\]8 It is seen that as the radio range increases, there is a decreasing trend in the safety period for radio range values up to 92 units, except for when the radio range is 77 units. After that, again the safety period sees an increasing trend. The safety period is highest when the radio range is 77 units. The capture ratio metric vs. radio range plot is seen in \[H_{11}=\frac{\frac{2R}{3}-d}{r_{s}\times p_{r}},\]9 This metric has an alternating increase and decrease in the values as the radio range increases. The capture ratio is the least when the radio range is 77 and 87. Figures 12 and 13 indicate that a radio range value of 77 units gives better results in terms of safety period and capture ratio. \[H_{12}=\frac{180^{\circ}}{\theta},\]0 Delay. \[H_{12}=\frac{180^{\circ}}{\theta},\]1 Network lifetime. \[H_{12}=\frac{180^{\circ}}{\theta},\]2 Energy consumption. Figures 14-16 show the plots for entropy, energy consumption, and delay metrics. It is seen that these three metrics almost have the same magnitudes for all the settings of the radio range, with minor deviations in energy consumption. It can be concluded that these three metrics are not much influenced by the radio range of the sensor nodes. The plot in Figure 17 is for the network lifetime metric. It is evident that the network lifetime metric is largely influenced by the radio range of the sensor node. The inference is that for the given spacing arrangement of the nodes in the network, a smaller radio range has a better network lifetime. Overall, it is concluded that the radio range of 77 units is doing good in terms of safety period and 72 radio range units is good for capture ratio and network lifetime. It is observed that when the sensor nodes' radio range increases, the safety period and the network lifetime decrease. Future studies could investigate the cause of this behavior. ### Discussions

A list of all metrics that have been averaged over each scenario setting are found in this section. These average values are shown in \[H_{12}=\frac{180^{\circ}}{\theta},\]3 We use shortest path routing (SPR) as our reference methodology to determine the percentage of increase or decrease. The table shows an improvement in SLP performance. The SLP-E's safety period has grown by 6379 times compared to SPR, while SLP-R, SRR, PRLRPW, and PSSLP have improved 5024-, 3185-, 2803-, and 5479-fold, respectively.