Device-to-Device (D2D) communication in a 5G network offers direct interaction between devices in close vicinity, bypassing the need for 5G network infrastructure for user data transmission. This approach enhances network performance by reducing traffic on the 5G core network, extending coverage, and minimizing communication latency. D2D communication is classified into three use-case scenarios based on the network’s coverage: In-coverage, Relay coverage, and Out-of-coverage. In the In-coverage scenario, both communicating devices operate in the network’s coverage area. As D2D communication gains increasing attention, the need for a secure authentication and key agreement scheme becomes paramount. While public key infrastructure (PKI) solutions, such as RSA and ECC, are widely used, they are vulnerable to quantum attacks, particularly Shor’s algorithm. To address this challenge, we propose a lightweight authentication and key agreement scheme. The significance of the proposal is that it enhances resistance to quantum attacks by leveraging symmetric key techniques and the SHA3-512 hash function, offering robustness against Grover’s algorithm and avoiding vulnerabilities associated with Shor’s algorithm. This ensures a higher level of security in anticipation of emerging quantum threats, given the rapid advancements in quantum computing. Validation through BAN logic and AVISPA confirms the scheme’s resilience against various threats, while performance analysis highlights its efficiency with minimal computation and communication overhead. The computation overhead of the devices is measured at 931.04 ms for the Arduino Uno Rev 3, 37.14 ms for the ESP8266, and 2.96 ms for the Raspberry Pi 4, while the communication overhead is measured to be 7920 bits.

Identity privacy is a security issue that is crucial for the users of a cellular network. Knowledge of the permanent identity of a user may allow an adversary to track and amass comprehensive profiles about individuals. Such profiling may expose an individual to various kind of unanticipated risks, and above all may deprive an individual of his right to privacy. With the introduction of sensitive services like online banking, shopping, etc. through cellular phones, identity privacy has now become a bigger security issue. In GSM and UMTS, the problem of user identity privacy vulnerability is proven to exist. In both these systems, there are situations where the permanent identity of a subscriber may get compromised. Long Term Evolution (LTE), which evolved from GSM and UMTS, is proposed by 3GPP for inclusion into the fourth generation of cellular networks. Although security of LTE has evolved from the security of GSM and UMTS, due to different architectural and business requirements of fourth generation systems, LTE security is substantially different and improved compared to its predecessors. However, the issue of identity privacy vulnerability continue to exist in LTE. In this paper, we discuss how the security architecture of LTE deals with identity privacy. We also discuss a possible solution that may be utilised to overcome the problem of user identity privacy in LTE.