## 5 Performance Analysis  
This section compares the proposed protocol with the last three years of UAV communication protocols in terms of security and computational overhead. * Comparison of safety characteristics  
Table 9 shows a comparative analysis between the security properties of the protocols that shows the proposed protocol performs well and satisfy the requirements in all the given security properties. The literature [31, 32, 33] all satisfy anonymity, session key agreement, resistance to replay attacks, man-in-the-middle attacks and DoS attacks. In perfect forward secrecy, it is found that literature [32] does not satisfy the requirements. In addition, there is no mention of perfect backward secrecy in the literature [31, 32, 33]. As a result, if any long-term key used to derive past session keys has been made public, the adversary can use the session key to recover the encrypted message to obtain sensitive data, making subsequent sessions vulnerable to various attacks if any current long-term key is damaged. Previous protocols [31, 32] are not able to resist privileged insider attacks. For resisting drone capture attacks, those described by [31] do not satisfy the requirements; and in [32] the problem is not mentioned. \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Security Features**} & \multicolumn{4}{c}{**Schemes**} \\ \cline{2-5}  & **Ref. [31]** & **Ref. [32]** & **Ref. [33]** & **Our Scheme** \\ \hline Anonymity & \(\surd\) & \(\surd\) & \(\surd\) & \(\surd\) \\ Perfect Forward Secrecy & \(\surd\) & \(\times\) & \(\surd\) & \(\surd\) \\ \hline \hline \end{tabular}
\end{table} 
Table 9: Comparison of safety characteristics. * Comparison of node overhead calculations  
Let \(T_{H}\) represent the execution time of Hash function operation; \(T_{F}\) represents the execution time of Fuzzy extractor operation; \(T_{E}\) represents the execution time of exponentiation operation; \(T_{SM}\) represents the execution time of Elliptic curve scalar point multiplication operation; \(T_{BP}\) represents the execution time of Bilinear pairing operation; \(T_{X}\) represents the execution time of XOR operation; \(T_{N}\) represents the execution time of pseudo-random number generation; \(T_{K}\) represents the execution time of Key encryption and decryption operation; \(T_{A}\) represents the execution time of elliptic curve point addition operation; \(T_{C}\) represents the execution time of Concatenation operation; \(T_{S}\) represents the execution time of Digital signature operation. The results are derived from a system with Intel Dual core 2.40 GHz processor, 18.04.5 Ubunt operating system, and 5.7 GB RAM. The time of each operation is used as given in [34,35]: \(T_{H}\) takes 0.0023 ms, \(T_{F}\) takes 5.427 ms, \(T_{E}\) takes 1.25 ms, \(T_{SM}\) takes 2.26 ms, \(T_{BP}\) takes 5.811 ms, \(T_{X}\) takes 0.000126 ms; \(T_{N}\) takes 0.00253 ms \(T_{K}\) takes 3.85 ms \(T_{A}\) takes 0.0288 ms,\(T_{C}\) takes 0.00587 ms, \(T_{S}\) takes 1.25 ms. In the proposed protocol, the computation cost for UAV and GCS are \(2T_{X}+2T_{SM}+T_{N}+3T_{H}+5T_{C}+2T_{S}+T_{K}\) and \(2T_{X}+T_{SM}+T_{N}+2T_{H}+3T_{C}+T_{S}+T_{K}\). Therefore, the total computed consumption is \(4T_{X}+3T_{SM}+2T_{N}+5T_{H}+8T_{C}+3T_{S}+2T_{K}\), about 18.298 ms. On the other hand, the schemes of Refs. [31, 32, 33] need approximately 32.12 ms, 19.152 ms and 29.0818 ms, respectively, as shown in Table 10 and Figure 9. This cost is better than the schemes of Refs. [31, 32, 33]. The proposed protocol is more balanced in terms of computational cost across nodes and the total computational cost is moderate. * Comparison of communication overheads  
In this section, we compare the communication costs of the different participants involved in the transmission of messages during the authentication and key negotiation phases.