Random Interleaving at MAC Layer for Privacy Protection in 6G RAN

In radio networks, the MAC layer control information is exchanged in the form of MAC-Control elements. These MACCEs are used for various purposes such as activation/deactivation of secondary cells in case of carrier aggregation, switching of bandwidth parts, timing advance commands. Due to its dynamicity as compared to higher layer signaling, the number of MAC-CEs being defined in 5G for use in different features is constantly on the rise. However, unlike the higher layers in the wireless protocol stack which are secured using integrity protection and encryption algorithms, the MAC sub layer is unprotected. This lack of a security mechanism in the MAC sublayer is a cause for concern as it leaves the RAN network open to security attacks such as tracking of users, denial of service, etc., In 6G, MAC layer security in radio interface is considered as an important aspect. This paper proposes a random interleaving technique for encrypting the data at MAC sub layer without any significant increase in the computation time, processing and delay.