The advancement of Internet of Vehicles (IoV) technologies has significantly enhanced road safety and transportation efficiency through smart traffic management and precise control systems. With the advent of 5G and beyond, vehicles within the IoV ecosystem can seamlessly communicate with various smart entities (X) using V2X (Vehicle-to-Entity) communications. However, the openness of IoV networks and the exponential growth of V2X links have expanded potential attack surfaces, increasing the risk of security and privacy breaches. In response to these challenges, this article proposes a privacy-preserving and secure communication framework for IoV networks, addressing critical security challenges in V2X communication. By leveraging lightweight cryptographic mechanisms such as hash functions, quadratic residuosity, and Legendre symbols, the proposed scheme ensures secure authentication, group key sharing, and pseudonym management within IoV networks. The proposed scheme's security and privacy features, along with its correctness, have been rigorously validated against various security threats where other state-of-the-art schemes fail. Comprehensive performance analysis demonstrates that our scheme completes authentication in a fraction of a millisecond, significantly outperforming existing approaches. The design simplicity and efficiency of the proposed authentication structure make it highly suitable for real-world IoV applications. 

One of the major challenges in implementing agroup key establishment and management scheme to providesecurity solutions for group communication in the Internet of Things (IoT) is the limited resource availability of the nodes suchas memory, computation, and energy. To ensure security such as confidentiality, integrity of the transmitting messages in a certain IoT group, a feasible group key establishment and management scheme is necessary which uses minimum resources but provides high scalability and strong security. In this paper, we propose asymmetric group key establishment scheme that uses the secrecy guarantee provided by One Time Pad (OTP) and performs computations like bitwise Exclusive OR (XOR) and bit shifting of randomly generated binary vectors to produce random different keys for different sessions of message transmission. We show that our scheme is lightweight to support the resource-constrained nature of IoT nodes by using only primitive operations and scalable to support the dynamic constellation of IoT network groups where nodes can join and exit frequently. We prove that our scheme is secure under a designed threat model where a similar existing scheme fails by a detailed analysis

Vehicular Ad-Hoc Networks (VANETs) offer enhanced road safety, efficient traffic management, and improved vehicle connectivity while dealing with privacy and security challenges in public communication. In these networks, authentication mechanisms are mandatory to establish trust among communicating entities, such as vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I), without losing identity and location-based privacy. The prevailing conventional authentication mechanisms frequently depend on a centralized trust authority (CA) to ensure the mutual verifiability of transmitted messages. Nevertheless, in scenarios where the density of vehicles within the network is notably high, an overwhelming influx of authentication requests may result in a communication bottleneck at the CA, leading to a single point of failure. This paper proposes a novel distributed authentication scheme in a decentralized VANET with multiple independent CAs connected to multiple local inspectors to eliminate a single point of failure. Furthermore, prior solutions lack the capability to immediately revoke a disputed vehicle that is transmitting malicious messages in the network. In this regard, the proposed scheme also facilitates an immediate revocation of a disputed sender to prevent other vehicles from further receiving malicious messages. As vehicles share time-sensitive data for driving assistance, our scheme minimizes the computation and communication costs for V2I key sharing and direct V2V authenticated message sharing significantly compared to previously proposed schemes. Using comparatively lightweight elliptic curve cryptography and eliminating the direct involvement of CAs in the authentication process, we have reduced the overall delays and achieved a maximum of ≈ 3.9 times faster V2I authenticated key sharing, and a maximum of ≈ 7.5 times faster V2V message sharing compared to state-of-the-art bilinear pairing-based protocols. A comprehensive efficiency analysis validates our scheme's ability to outperform time-sensitive responses, such as sending and receiving an alert within nearly 4 milliseconds. 

Vehicular Ad Hoc Networks (VANETs) play a crucial rolein the evolution of Intelligent Transportation Systems. The problems ofrenting and drivers’ accountability still need to be answered in VANETs.Existing proposals do not consider renting vehicles, and there is nodistinction between renters and owners. This paper proposes privacy-preserving rental and accountability protocols to address these problems.The proposed rental protocol outputs an agreement between an ownerand a renter, which allows the renter to unlock and drive the vehicle.The privacy-preserving accountability protocol offers a robust solutionfor detecting and mitigating malicious behavior in VANETs. It provides aplatform for holding entities accountable for their actions without violating their privacy. The paper demonstrates that our solution successfullymeets the pre-set security and privacy requirements in VANETs. Thesefindings suggest promising potential for improving future vehicular networks’ safety, efficiency, and performance.