## 5 Conclusions  
This study introduced a blockchain and Kerberos-based authentication framework for VANETs, which encapsulated authentication messages within blockchain blocks. The practicability of implementing blockchain technology and the network's performance were evaluated. We executed three experiments to test the applicability of the system in diverse network scenarios to fulfill network and blockchain requirements. In the first scenario, we tested the proposed system in a suburban area with 100 vehicles and 1 TAS. In the second scenario, we changed the environment to an urban area that had an increased number of vehicles of 200, without any TAS addition. In the third scenario, we used the second scenario environment with one TAS addition. The performance of the system was assessed through network performance and blockchain performances impacted by TAS and the number of vehicles. Network performance included authentication, handover, and end-to-end delays. The blockchain performances included the gas value and the block size. The study revealed that, in the first scenario, the system fulfilled all of the network requirements. However, in the second scenario it did not fulfill the authentication delay requirement of \begin{table}
\begin{tabular}{p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt}} \hline \hline
**Reference/Year** & \begin{tabular}{c} **Vehicles for** **Simulation** \\ \end{tabular} & \begin{tabular}{c} **Kerberos** \\ **Integration** \\ \end{tabular} & \begin{tabular}{c} **Encryption** \\ **Technique** \\ \end{tabular} & \begin{tabular}{c} **Gas and Cost** \\ **Calculation** \\ \end{tabular} & \begin{tabular}{c} **Delay Evaluation** \\ **Analysis** \\ \end{tabular} & \begin{tabular}{c} **Security Attack** \\ **Analysis** \\ \end{tabular} \\ \hline [12]/2020 & 25–50 & \(\times\) & not defined & \(\times\) & Yes, end-to-end delay & \(\times\) \\ \hline [13]/2020 & not defined & \(\times\) & AES and CCMP & ✓ & \begin{tabular}{c} Yes, authentication \\ delay \\ \end{tabular} & ✓ \\ \hline [14]/2020 & 1–50 & \(\times\) & ECC & \(\times\) & Not Evaluated & ✓ \\ \hline [15]/2022 & 10–50 & \(\times\) & ECC & \(\times\) & Yes, end-to-end delay & ✓ \\ \hline [16]/2023 & 25–200 & \(\times\) & ECC & ✓ & \
\begin{tabular}{c} Yes, authentication \\ delay \\ \end{tabular} & ✓ \\ \hline [50]/ 2018 & 1–50 & \(\times\) & ECC and IBE & \(\times\) & Yes, end-to-end delay & ✓ \\ \hline [51]/2024 & 20–100 & \(\times\) & ECC & \(\times\) & Not evaluated & ✓ \\ \hline Proposed/2024 & 1–200 & ✓ & AES-128 & ✓ &
\begin{tabular}{c} Yes, authentication \\ delay, handover delay, and end-to-end delay & ✓ \\ \hline \hline \end{tabular}
\end{table} 
Table 8: Comparison of proposed method with existing literature. VANETs because it exceeded the maximum limit of 100 ms. The third scenario overcame that authentication delay problem by increasing the number of TASs to two. Concerning blockchain practicability, although the gas value and memory size of the system rose linearly with vehicle quantity, the system remained practicable as it did not exceed the maximum allowable gas value and memory size of the block. All of the findings showed that our proposal is applicable to be implemented in diverse network scenarios with the addition of a TAS. In future work, we would like to vary the vehicle's communication range in the system, which can reduce broadcast-storm and frequent disconnections when the vehicular density is high. Conceptualization, M.R. and S.H. ; methodology, M.R. and S.H. ; software, M.R. and M.B.H. ; investigation, M.R., M.B.H., S.H., M.A.A., Y.K. and Y.N. ; resources, M.R. and Y.N. ; data curation, M.R. and M.B.H. ; writing--original draft preparation, M.R., M.B.H. and S.H. ; writing--review and editing, M.R., M.B.H., S.H., M.A.A., Y.K. and Y.N. ; visualization, M.R. ; supervision, S.H. and Y.N. ; project administration, S.H. and Y.N. All authors have read and agreed to the published version of the manuscript. This research received no external funding. Not applicable.