# A Robust and Energy-Efficient Weighted Clustering Algorithm on Mobile Ad Hoc Sensor Networks +
## 5 Simulation Results and Discussion
Within a short distance, the RE\({}^{2}\)WCA is similar to the DWCA and EMDWCA, however, in the long distance, the throughput of RE\({}^{2}\)WCA is obviously greater than the DWCA and EMDWCA since the proposed algorithm can elect the optimal \(CH\), which can accelerate the message forwarding. The throughput is nearly 10% greater than the EMDWCA and nearly 15% greater than DWCA respectively. Figure 11: Surviving nodes vary with Round number. Figure 12: Throughput of the network. (**a**) Network throughput varies with the distance. (**b**) Network throughput under certain fault nodes. In Figure 12, with the number of fault nodes increasing, the throughput of DWCA is decreased rapidly. On the meanwhile, the throughput of EMDWCA and RE\({}^{2}\)WCA decreased slowly since in order to increase robustness of network, both of them introduce fault nodes detection algorithm. In RE\({}^{2}\)WCA, the redundancy of the network is not increased but a mechanism of fault detection is introduced. The EMDWCA increases the redundant links of the nodes, which increases the routing overhead and consume more energy to construct links. Therefore, the throughput will be degraded. When the proportion of fault nodes reaches to 16%, the throughput of three types protocols decreased dramatically since many clusters cannot work normally. Actually, the proportion of fault node cannot reach so highly, thus, RE\({}^{2}\)WCA remains to maintain a better throughput than DWCA and EDWCA protocols. Figure 13 displays the effect of mobility on the packet drop rate. With increasing in the mobility of nodes, link failures occur causing more packets to be dropped on way. This decrease is less in RE\({}^{2}\)WCA algorithm because of the use of mobility thresholds as well as group mobility. Figure 14 shows the energy consumption of the whole network. We can conclude that DWCA consumes energy fastest, EMDWCA second and RE\({}^{2}\)WCA slowest. The energy consumption is vital in sensor network, however, DWCA fails to control the energy consumption reasonably, therefore when the round number is nearly 700 rounds, the network is paralyzed. In EMDWCA, the lifetime of the network is relatively longer because the \(CH\) election considers the residual energy. Unfortunately, since the increased routing overhead and constructed redundancy link, the energy still consumes fast, therefore when the round number is nearly 1100 rounds, the network is paralyzed. However, the proposed algorithm can reach 1220 rounds, because we not only consider the residual energy but also exclude the fault nodes so that network can proceed the topology maintenance which can save amount of energy caused by the times of failed routing. The energy consumption of network which is conducted in RE\({}^{2}\)WCA protocol is 50% less than DWCA and 15% for EMDWCA respectively. In conclusion, we discuss the cluster application from different aspects which are throughput and network energy consumption. The throughput actually reflects the lifespan of the network and data transmission ability. Network energy consumption however, demonstrates the energy-efficiency, which indirectly implies the lifetime of network. From the simulations results, we can conclude that our protocol, RE\({}^{2}\)WCA, is superior to original two protocols, EMDWCA and DWCA respectively  
Figure 13: Number of packages dropped varies with Mobility parameter.