Leveraging Group Secret Sharing Technology for FD-RAN: A Lightweight AKA Mechanism
Ning Wang, Jiacheng Chen, Jianbing Ni, Liquan Chen, Haibo Zhou · 2024
With rapid advances in communication technology, a new access architecture of fully decoupled radio access network (FD-RAN) has been proposed. FD-RAN completely decouples the base station (BS) into uplink data base station (UBS), downlink data base station (DBS), and control base station (CBS). Different BSs handle the uplink and downlink data of the user plane, as well as control signaling, and facilitate communication needs through multi-BS cooperation. To ensure the security of multi-BS cooperation and user access, it becomes imperative to conduct key negotiations among multiple parties. However, as the number of simultaneously accessed BSs increases, the existing access security mechanism imposes excessive overhead in FD-RAN, compromising both access security and efficiency. Additionally, it becomes susceptible to distributed denial of service (DDoS) attacks launched by potential attackers. This paper introduces a lightweight authentication and key agreement (AKA) protocol based on secret value ($m_{i},\ n_{i}$) sharing technology to negotiate multi-BS group communication keys, which ensures access security in FD-RAN. By leveraging interpolation polynomial and multi-party key negotiation, the proposed protocol achieves efficient and cost-effective key negotiation on both the user and BS sides, which mitigates the risk of man-in-the-middle (MitM) and DDoS attacks. Security analysis and further evaluation show that the proposed scheme can resist various known attacks, and guarantee the computational and communication efficiency of key negotiation within the FD-RAN context.