GreenFlow VANET: 5G-Enabled Secure and Energy-Efficient Routing for Smart Cities

The rapid proliferation of smart cities and Intelligent Transportation Systems (ITS) demands revolutionary approaches to vehicular communications that can simultaneously address energy efficiency, security, and quality of service requirements. This paper presents GreenFlow VANET, a novel 5G-enabled secure and energy-efficient routing protocol specifically designed for smart city deployments. Our approach leverages a three-tier architecture integrating Vehicle Ad-Hoc Networks (VANETs) with 5G Ultra-Reliable Low-Latency Communication (URLLC), enhanced Mobile Broadband (eMBB), and massive Machine Type Communication (mMTC) network slices. The GreenFlow Secure Routing Protocol (GF-5G-SRP) introduces MEC-assisted route discovery, multi-criteria next-hop selection incorporating 5G quality metrics, and adaptive energy management techniques. Our security framework employs ECC-256 cryptography, ChaCha20-Poly1305 encryption, and distributed trust management to ensure robust protection against vehicular network threats while preserving location privacy through SUPI/SUCI mechanisms. Extensive simulations using NS-3 with 5G-LENA and SUMO mobility models demonstrate that GreenFlow VANET achieves 96.8% packet delivery ratio, 59% energy reduction compared to traditional approaches, and 81% improvement in network lifetime while maintaining sub-millisecond latency for safety-critical communications. The proposed solution effectively addresses the scalability challenges of dense urban vehicular networks with up to 1000 vehicles while providing comprehensive security with 97.8% attack detection rates and minimal false positives.