Physical-layer authentication for wireless security enhancement: current challenges and future developments
While the open nature of radio propagation enables convenient “anywhere” wireless access, it becomes the root of security vulnerabilities in wireless communications. In light of this, physical-layer authentication, which is based on exploitation of the dynamics of physical layer attributes, is emerging as an effective approach to enhancing wireless security. In this article, we first review the existing physical-layer authentication techniques and identify their current limitations, ranging from low authentication reliability to the difficulties of integrating these techniques with the existing wireless infrastructure and applying them in complex future networks. We then present three promising research areas in addressing these challenges. Specifically, we propose the use of the multi-attribute multi-observation technique for enhancing the authentication reliability. In order to apply pointto- point physical-layer authentication techniques into existing wireless networks, we propose a cross-layer authentication approach relying on a composite security key that can seamlessly integrate physical-layer and upper-layer authentication schemes. We also discuss possible ways of invoking physical-layer authentication to reduce both the complexity and latency of the security processes in complex heterogeneous networks with the aid of the proposed physical security context sharing.