5G内生安全技术：跨层认证

5g network adopts the traditional upper layer authentication as the access authentication protocol, which is vulnerable to man-in-the-middle attack. Physical layer authentication uses the physical information for authentication, which perfectly solves the problem. This paper summarizes the origin and research status of physical layer authentication. Then, applying physical layer authentication to 5G network, 5G cross layer authentication protocol based on wireless channel features is proposed. Experimental verification is carried out. Simulation test results show that 5G cross layer authentication protocol can resist man-in-the-middle attack, and performs better than standard 5G authentication protocol.