Secure Routing in VANET Systems Using Fog Computing and Software Defined Networks

Vehicular ad hoc networks (VANETs) are crucial for enabling secure, low-latency communications in intelligent transportation systems. This paper proposes Secure Routing using SDN and Fog (SRSF), a novel protocol that integrates softwaredefined networking (SDN), fog computing, permissioned blockchain, and adaptive authenticated encryption (AEAD). SRSF dynamically selects between AES-GCM and ChaCha20-Poly1305 ciphers based on real-time network load and security risk, optimizing both performance and resilience. Extensive NS-3 simulations demonstrate that SRSF outperforms existing protocols in terms of end-to-end delay, throughput, and packet delivery ratio, especially under attack scenarios. The protocol achieves over 98% Sybil detection and complete mitigation of replay attacks, with statistical validation confirming the significance of observed improvements. These results highlight SRSF as an effective and scalable solution for secure data routing in VANET environments.