## 4 Privacy-Preserving Optimization Based on Advanced CH Selection (P2O-ACH)
### Enhanced ROA-Based CH Selection
In terms of speed variation, the routing overhead of the P2O-ACH is increased by up to 130 packets, and the performance of the earlier work GWO-CH is increased by 310 packets; ACO-SCRS is increased by 400 packets; and QMM-VANET is increased by 280 packets. From the analysis, it is proved that the routing overhead performance of the proposed P2O-ACH is lesser than the other works. The throughput of the proposed P2O-ACH improved from 356 Kbps to 489 Kbps, whereas earlier works, such as GWO-CH, ACO-SCRS, and QMM-VANET, improved from 121 Kbps to 156 Kbps, 153 Kbps to 175 Kbps, and 212 Kbps to 259 Kbps, respectively. In terms of speed variation, the throughput of the P2O-ACH increased up to 150 Kbps, and the performance of the earlier work GWO-CH improved by 35 Kbps; ACO-SCRS improved by 30 Kbps; and QMM-VANET improved by 45 Kbps. From the analysis, it is stated that the throughput of the proposed P2O-ACH is more improved than the others. This detail's analysis in terms of both the number of vehicles and speed shows that the overall performance of the proposed P2O-ACH is better when compared with the earlier works, such as GWO-CH, ACO-SCRS, and QMM-VANET. ### Algorithm Comparison

In the GWO-CH method [36], a grey wolf optimization algorithm-based clustering approach is proposed to solve the scalability issues in the VANETs. The social characteristics and hunting of the grey wolf are utilized to find the effective CHs in the network. Through this method, the energy consumption, delay, and routing overhead of the network fail to improve the packet delivery ratio and throughput of the network. Due to a lack of security, packet loss occurred in the network, which affects the effectiveness of the network. In the ACO-SCRS method [37], the ant colony optimization (ACO) algorithm is used to rely on the bus selection and effective clustering to improve the communication standard of VANETs. The model improves the energy efficiency of the network, but fails to reduce the data loss which happens due to the ground-level obstacles in the VANETs environment, which is reflected in the effective communication in the network. In the QMM-VANETs model [38], to improve the connectivity and network stability, an improved trust-based clustering algorithm is proposed so that trusted vehicles are introduced in the network, which leads to reduced packet loss, and the energy consumption is also reduced; however, this method consumes more energy when it reaches high speed with dynamic mobility. The major drawbacks, which are identified in the earlier approaches, are low density of vehicle, high packet loss due to ineffective security, and high delay and overhead. To solve these issues, in the proposed P2O-ACH approach, an efficient optimization with CH selection and the privacy-preserving mobility model is introduced, which concentrates on reducing the energy consumption and packet loss in an effective manner so that it directly improves the energy efficiency, packet delivery ratio, and network throughput. In terms of algorithm, when compared with the grey wolf optimization and the ant colony optimization, our enhanced ROA optimization shows better performance in the parameters such as delay, overhead, and energy consumption. When compared with other CH selection processes, our method is highly effective in achieving high energy efficiency. The whole the overall performance of the proposed P2O-ACH is better when compared with the earlier approaches, namely GWO-CH, ACO-SCRS, and QMM-VANET. ## 6 Conclusions

In this research, the major drawbacks to concentrate on are reducing energy consumption and improving security during the process of communication in VANETs. For this purpose, an efficient privacy-preserving mobility model and enhanced ROA-based CH selection are implemented, and they greatly improve the overall performance of the network by reducing energy consumption and congestion as well as improving the security of the network. Advanced CH selection is performed, which becomes a great solution for security and energy utility issues.