The continuous growth to the 6G wireless communication technology overcomes storage, stringent computation, privacy and power constraints to make an efficient and intelligent next generation transportation system to alleviate traffic jams and enhance driving experience in vehicular ad-hoc networks (VANETs). In combination with 6G technology, high availability, high reliability and occasionally high throughput are enabled in VANETs. However, the information shared in the VANET system should be secured. In this paper, an efficient batch authentication and key exchange schemes are proposed to provide a high level security by evading communication with the malicious vehicle users. In addition, an anonymous batch authentication scheme is proposed to alleviate the authentication burden on the road side units (RSUs) while performing authentication in the congested areas. Moreover, the integrity of the communicating messages is preserved in this proposed scheme to evade message modification during transmission. Even though many cryptographic schemes were proposed for batch authentication in VANETS, they suffered from lack of privacy-preservation and computational overhead. The discussion of the possible attacks section illustrates that the proposed protocol can survive against potential security attacks. In the performance analysis section, the proposed batch authentication scheme is compared with well-known existing schemes and then it is clearly revealed that the proposed scheme is computationally more efficient than the existing schemes.

Internet-of-Things (IoT)-based wireless body area networks (WBANs) play an important role in modern medical systems for patient-health monitoring. WBANs have the capability to collect real-time biological information from the patients' body using intelligent sensors and then send the collected information to the remote doctors or medical experts using the Internet. In recent years, numerous anonymous authentication schemes were proposed to provide security in WBANs. However, many of these schemes are not computationally efficient during anonymous authentication. Moreover, the previous schemes did not provide location privacy for both doctors and patients. In order to overcome these limitations, in this article, we propose an efficient and secure anonymous authentication framework with location privacy preservation for IoT-based WBANs. The comprehensive analysis section shows that the proposed scheme overcomes the security weaknesses in the existing schemes and also provides low computation cost during anonymous authentication.

In this work, a secure and decentralized Blockchain based energy trading model for electric vehicles (EVs) using Smart contract that achieves Peer-to-Peer (P2P) transactions between EVs in Vehicle to Grid networks is designed. The traditional energy trading model is a centralized structure based on trusted third parties, and there may an issue of single-point failure and leakage of privacy. In this way, a blockchain-based framework offers a secure, efficient and transparent trading model. Initially, the participating EVs and aggregator in the trading process should register at the trusted authority. Once the registration is successfully completed, both EVs and aggregator authenticate each other mutually in an anonymous manner. Moreover, only authorized EVs (charging and discharging EVs) participate in the contrary auction mechanism to exchange power/money based on their demand. Simulation conducted for the proposed scheme shows that our scheme has high speed (i.e., less computational time and execution time) which improves the market efficiency. In-addition, the transactions are non tamperable, when compared to the conventional scheme.

Smart driving has become conceivable due to the rapid growth of vehicular ad hoc networks. VANETs are considered as the main platform for providing safety road information and instant vehicle communication. Nevertheless, due to the open wireless nature of communication channels, VANET is susceptible to security attacks by malicious users. For this reason, secure anonymous authentication schemes are essential in VANETs. However, when vehicles reach a new roadside unit (RSU) coverage area, the vehicles need to perform reauthentication with the current RSU, which significantly diminishes the efficiency of the entire VANET. Therefore, the introduction of blockchain technology has created opportunities for VANETs to resolve the aforementioned challenges. Due to the decentralized nature of blockchain technology, rapid reauthentication of vehicles is achieved in this paper through secure authentication code transfer between the consecutive RSUs. The security strength of the proposed blockchain-based anonymous authentication scheme against various harmful security attacks is proven in the security analysis section to ensure that it provides better security. In addition, blockchain, as presented in the performance analysis section, is used to substantially diminish the computational cost compared to conventional authentication schemes.

The recent developments in the wireless body area networks (WBAN) play a vital role in the modern remote health care monitoring system. In WBAN, the deployed intelligent, resource-limited body sensors will collect the patient's biological information (BI) and communicate the same to the doctor for further action through the Internet. But during the communication among the WBAN entities, the privacy, security of the BI, and user's personal data need to be protected against various security threats. To address these security flaws, in this article, a computationally efficient privacy-preserving anonymous authentication scheme is proposed for resource-limited WBAN. Also, it preserves the physical security of sensors and the confidentiality of BI and provides conditional privacy to the WBAN users. The comprehensive security and performance evaluation phase ensures that the proposed scheme is efficient and secure in terms of computational and communication complexity when compared with the other conventional schemes.