EEGAP: ECC-Based Efficient Group Authentication Protocol for Dynamic Vehicular Platoon

Vehicular platooning has emerged as a promising paradigm in intelligent transportation, offering significant benefits such as reduced energy consumption, improved road throughput and mitigated traffic congestion. However, the open nature of vehicular communication channels exposes platoons to a wide range of security and privacy threats. Although existing group key-based protocols provide foundational security services, they often incur substantial computation overhead and insufficiently address vehicle privacy, making them unsuitable for dynamic vehicular platoon. Therefore, this paper introduces an efficient group authentication protocol (EEGAP) for dynamic vehicular platoons, which ensures privacy-preserving and secure communication during platoon restructuring operations, such as merging and splitting, by integrating anonymous authentication, fog computing, and group key agreement mechanisms. Leveraging Elliptic Curve Cryptography (ECC) and secret sharing mechanisms, EEGAP enables lightweight yet robust group key negotiation, reducing computation overhead by 7.08% and communication overhead by 6.85% compared to existing schemes. Both formal security proofs and informal analysis confirm that EEGAP satisfies the stringent security requirements of vehicular platoon communication systems.