The rapid evolution of vehicles leads to future vehicular technologies which improve transportation systems. One prominent technology is platooning networks where a vehicle, called platoon head, leads to a group of vehicles. Platoons not only improve the vehicle driving experience and safety but also reduce traffic congestion. Despite all these benefits, the authentication of vehicles for platoon networks is a critical problem in order to share and get access control to other vehicles. Moreover, due to the platoon networks’ complexity and high dynamic formation, it requires an efficient and robust authentication mechanism between vehicles. In this paper, we propose a blockchain-based authentication protocol for platoons using the concept of the platoon as a service. Our approach not only proposes an efficient protocol that reduces the computation and communication for the authentication but also improves the security with the use of a distributed authentication (Auth-I) data ledger across the network and a token-based platoon authentication (Auth-II), which is suitable for practical implementations in areas with different traffic density.

With the fast evolution of vehicle networks, Connected and Autonomous Vehicles (CAVs) are mobile devices that are not only used for transportation but also form part of other promising technologies such as the internet of vehicles and cyber-physical systems. Despite the benefits of CAVs, exposing in-vehicle networks to external devices can lead to different privacy and security challenges. Due to scalability, efficiency, and dynamic communication requirements, the security between in-vehicle networks with external devices cannot fully rely on the vehicle's external third parties. In this paper, we propose a semi-decentralized fine-grained security framework based on Ciphertex-Policy Attribute-Based Encryption (CP-ABE) to secure the communication of in-vehicle network's Electronic Control Units (ECUs) with vehicle's external connected device. Our approach's fine-grained access control is based on the attributes of external devices connected to different subsystems inside the vehicle. Each subsystem inside the vehicle has full control of the access policy during the vehicle's operation. Therefore, our proposed approach has a flexible and dynamic key management suitable for future CAVs. Finally, the experiment of our framework validates its feasibility for implementation.

Despite the benefits of electric and autonomous vehicles, current in-vehicle networks lack a robust and feasible security framework that considers the authentication, confidentiality, and integrity for the communication of Electronic Control Units (ECUs). Although a centralized key management mechanism offers an efficient solution, the security fully relies on this centralized unit, which leads to a single point of failure problem. In this paper, we present a semi-centralized key management framework to secure in-vehicle networks. It provides a decentralized and dynamic key distribution during the vehicle's operation and considers different aspects such as ECU's broadcast communication, ECU manufacturing process and ECU authentication without the use of certificates from external third parties. Finally, the implementation and the simulation of our framework validate the feasibility and practical use of our approach.