# Integrated Authentication Server Design for Efficient Kerberos–Blockchain VANET Authentication

## TL;DR

This paper introduces a more efficient and secure authentication system for VANETs by combining two servers into one, improving performance and reducing costs.

## Contribution

The novel contribution is an integrated authentication server design that merges AS and TGS in a Kerberos–Blockchain system for VANETs.

## Key findings

- The integrated server reduces authentication delays to under 100 ms while maintaining security.
- Throughput improves by 104% and signaling overhead decreases by 45% compared to the previous system.
- The design eliminates the need for an additional server, lowering infrastructure costs.

## Abstract

Vehicular Ad Hoc Network (VANET) is a fundamental component of the intelligent transportation systems (ITS), providing critical road information to users. However, the volatility of VANETs creates significant vulnerabilities from malicious actors. Thus, verifying joining entities is crucial to maintaining the VANET’s communication security. Authentication delays must stay below 100 ms to meet VANET requirements, posing a major challenge for security. Our previous research introduced a Kerberos–Blockchain (KBC) authentication system that contains two main components separately: Authentication Server (AS) and Ticket Granting Server (TGS). However, this KBC architecture required an additional server to accommodate increasing vehicle volumes in urban environments, leading to higher infrastructure costs. This paper presents an integrated authentication server that merges AS and TGS into a Combined Server (CBS) while retaining blockchain security. We evaluate it using OMNeT++ with SUMO for traffic simulation and Ganache for blockchain implementation. Results show that CBS removes the need for an extra server while keeping authentication delays under 100 ms. It also improves throughput by 104% and reduces signaling overhead by 45% compared to KBC. By optimizing authentication without compromising security, the integrated server greatly enhances the cost-effectiveness and efficiency of VANET systems.