Physical Layer Key Generation in 5G Wireless Networks

TL;DR

This paper reviews and proposes solutions for physical layer key generation in 5G networks, addressing challenges like eavesdroppers, high bit disagreement, and temporal correlation, to enhance security and reliability.

Contribution

It surveys existing methods and introduces novel solutions leveraging beamforming, mmWave channel sparsity, and hybrid precoding for improved key generation in 5G.

Findings

Beamforming enhances resistance to co-located eavesdroppers.

Utilizing mmWave channel sparsity reduces bit disagreement ratio.

Hybrid precoding decreases temporal correlation among samples.

Abstract

The bloom of the fifth generation (5G) communication and beyond serves as a catalyst for physical layer key generation techniques. In 5G communications systems, many challenges in traditional physical layer key generation schemes, such as co-located eavesdroppers, the high bit disagreement ratio, and high temporal correlation, could be overcome. This paper lists the key-enabler techniques in 5G wireless networks, which offer opportunities to address existing issues in physical layer key generation. We survey the existing key generation methods and introduce possible solutions for the existing issues. The new solutions include applying the high signal directionality in beamforming to resist co-located eavesdroppers, utilizing the sparsity of millimeter wave (mmWave) channel to achieve a low bit disagreement ratio under low signal-to-noise-ratio (SNR), and exploiting hybrid precoding to reduce the temporal correlation among measured samples. Finally, the future trends of physical layer key generation in 5G and beyond communications are discussed.