# HCLE: Hybrid Clustering Approach for Extending WBAN Lifetime
## 5 Simulation Results and Analysis
### Node Deployment
In the SIMPLE protocol, the residual energy of sensor nodes is drastically reduced after the first node dies (at round 6383). This rapid reduction occurs due to the speed at which all other nodes deplete their energy after the death of the first node. However, our proposed protocol (HCEL) and the ERRS protocol outperform the SIMPLE protocol, especially after the depletion of the first node. The better performance of our proposed and ERRS protocols is due to the use of a static and dynamic clustering-based routing mechanism. By allowing every sensor node to become a parent node, the load is evenly distributed among all nodes, extending their lifetime. Figure 5:0 Analysis of total number of dropped packets. Furthermore, the efficient selection of parent nodes and appropriate route selection in our proposed scheme (HCEL) play a significant role in the energy conservation of the deployed sensor nodes, thus extending the network lifetime compared to both the ERRS and SIMPLE protocols. The experiment in Figure 13 calculates an average EED for our proposed protocol (HCEL), as well as the SIMPLE and ERRS protocols. The results, shown in Figure 13, indicate that our proposed protocol achieves a lower delay than the SIMPLE and ERRS protocols. The key factor contributing to the improved EED in our protocol lies in the use of an adaptive static cluster routing mechanism, coupled with the careful selection of the parameters during parent node selection. That is, unlike the frequent selection of nodes closest to the sink as parent nodes in the SIMPLE protocol, our approach ensures a more balanced distribution of the traffic load among the nodes. This measure effectively mitigates rapid energy depletion at specific nodes, thereby enhancing the successful reception of packets at the sink and reducing the overall delay. As a result, our protocol shows an impressive improvement of approximately 56% compared to the SIMPLE protocol and approximately 40% compared to the ERRS protocol. Figure 5:1 Analysis of residual energy. Figure 5:2 Comparing the end-to-end delay among the HCEL, SIMPLE, and ERRS protocols. The following experiment, shown in Figure 14, analyzes the network cumulative path loss for our proposed protocol (HCEL), as well as for the SIMPLE and ERRS protocols. Using two-hop transmission in the routing protocol helps minimize the data transmission distance from the sensor nodes to the sink, resulting in lower path loss. Initially, our proposed protocol (HCEL) and ERRS protocol perform well compared to the SIMPLE protocol. However, starting from round 7981, all two-hop sensor nodes in the SIMPLE protocol deplete their energy, leading to a significant decrease in path loss. Consequently, the SIMPLE protocol exhibits a greater reduction in path loss compared to our proposed protocol (HCEL) and to the ERRS protocol from round 7981 to round 22,268. It is worth noting that the cumulative path loss is minimal when the number of alive nodes is minimal. Additionally, the increase in path loss observed in our proposed protocol (HCEL) and ERRS protocol during this period (rounds 6383 to 22,268) is due to its longer stability period and a higher number of alive nodes, contributing to the increased cumulative path loss. To address the overhead issue, efficient routing protocols aim to reduce the size of control packets. In our experiment, depicted in Figure 15, we analyze the communication cost in terms of bits for various numbers of rounds for our proposed protocol (HCEL), as well as for the SIMPLE and ERRS protocols. While the payload size remains the same (127 bytes) in all protocols, the difference lies in the overhead calculation. In the HCEL protocol, the overhead during the initialization phase in round 0 (63,424 bits) is lower compared to the SIMPLE protocol (94,080 bits). This is because one-hop sensor nodes do not participate in data forwarding or routing, eliminating the need to send their energy levels and RSSI values to other nodes or the sink in our protocol.