# Lightweight and Security-Enhanced Key Agreement Protocol Using PUF for IoD Environments
## 9 Conclusions  
This paper confirms that [PERSON]'s protocol is susceptible to session key disclosure and impersonation attacks by eavesdropping on public channel messages. Furthermore, [PERSON]'s protocol is unsuitable for the IoD environment due to the high communication and computation costs incurred using ECC. Therefore, this work proposes a robust and lightweight key agreement protocol for the IoD environment, addressing the limitations of [PERSON]'s protocol. The proposed protocol is resilient to various security attacks, including physical drone capture, session key disclosure, offline password guessing, and user impersonation attacks. Furthermore, the proposed protocol ensures anonymity, untraceability, and mutual authentication. This work confirms the session key security and mutual authentication of the proposed protocol using BAN logic and the RoR model, respectively. Moreover, this work uses the AVISPA simulation tool to demonstrate that the proposed protocol defends against replay and MITM attacks. Finally, this work reveals that the proposed protocol is more efficient regarding computational and communication costs by comparing the performance results of the proposed and relevant protocols. However, there are still significant challenges in applying our proposed protocol to real large-scale IoD environments, such as addressing various potential attack scenarios and optimizing computational and communication overhead. In future work, we plan to implement the proposed protocol on a testbed that is similar to a real IoD environment to verify the practical performance and security characteristics of the proposed protocol. In addition, we intend to investigate the potential integration of our proposed protocol with blockchain technology to improve its security and transparency.  
Conceptualization, S.L. and S.S.; Formal analysis, S.L. and S.S.; Methodology, S.L. and S.S.; Software, S.S.; Validation, S.L. and Y.P.; Formal Proof, S.S.; Writing--original draft, S.L. and S.S.; Writing--review and editing, S.L. and Y.P.; Supervision, Y.P. All authors have read and agreed to the published version of the manuscript.  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**SCF** & [25] & [26] & [27] & [28] & [13] & **Proposed** \\ \hline SCF1 & ✓ & ✓ & ✓ & ✓ & X & ✓ \\ SCF2 & ✓ & ✓ & ✓ & ✓ & X & ✓ \\ SCF3 & ✓ & ✓ & - & ✓ & X & ✓ \\ SCF4 & - & ✓ & ✓ & ✓ & - & ✓ \\ SCF5 & - & ✓ & - & - & - & ✓ \\ SCF6 & ✓ & - & ✓ & ✓ & X & ✓ \\ SCF7 & ✓ & ✓ & ✓ & ✓ & ✓ & ✓ \\ SCF8 & ✓ & ✓ & - & ✓ & ✓ & ✓ \\ SCF9 & ✓ & ✓ & ✓ & ✓ & ✓ & ✓ \\ SCF10 & ✓ & - & ✓ & ✓ & - & ✓ \\ SCF11 & ✓ & - & ✓ & ✓ & ✓ & ✓ \\ SCF12 & ✓ & - & ✓ & ✓ & ✓ & ✓ \\ \hline \hline \end{tabular}  
*: Not considered. X: Not secure. \(\gamma\): Secure.  
\end{table}
Table 9: Security feature comparison.  
**Funding:** This work was supported by a National Research Foundation of Korea (NRF) grant funded by the Korea government (Ministry of Science and ICT) (RS-2024-00450915).  
**Data Availability Statement:** Data are contained within the article.  
**Conflicts of Interest:** The authors declare no conflicts of interest.