An Integrated SDN–Blockchain Framework for Secure and Intelligent Communication in IoT-Enabled Vehicular Networks

Abstract

Intelligent transportation systems are increasingly relying on connected vehicles and Internet of Things (IoT) technologies to improve road safety, traffic efficiency, and real-time communication. Ensuring secure, reliable, and low-latency communication in highly dynamic vehicular environments remains a significant challenge due to frequent topology changes, high vehicle mobility, and growing cybersecurity threats. Conventional Vehicular Ad Hoc Networks (VANETs) often experience limitations in network management, resource utilization, and trust establishment, reducing their ability to support critical applications such as emergency vehicle communication. This study proposes an integrated Software-Defined Networking (SDN) and blockchain framework to provide intelligent network control and secure communication for IoT-enabled vehicular networks. The proposed framework employs a centralized SDN controller for dynamic Road Side Unit (RSU) allocation, adaptive routing, and priority-based communication, while blockchain technology ensures transaction authentication, data integrity, and decentralized trust using SHA-256 hashing and a lightweight Proof-of-Work consensus mechanism. The framework was implemented in Python with a Flask-based web dashboard and evaluated through simulation using network performance and blockchain metrics. The results demonstrate stable vehicle–RSU connectivity, efficient routing, successful blockchain transaction validation, and reliable priority communication for emergency vehicles. These findings demonstrate that integrating SDN with blockchain improves communication efficiency, network security, and resource utilization compared with conventional approaches. The proposed framework provides a scalable foundation for secure next-generation intelligent transportation systems and offers opportunities for future enhancement through distributed SDN controllers, lightweight blockchain consensus mechanisms, and edge computing integration.