Improved 5G message RCS access authentication IMS-AKA mechanism with balanced security and efficiency

The invention discloses an improved 5G message RCS access authentication IMS-AKA mechanism with balanced security and efficiency, and in the mechanism, UE and an HSS share key generation functions f3, f4 and f5 and a message authentication function H1; the UE and the S-CSCF share key generation functions f3'and f4 'and a message authentication function H2; the HSS and the S-CSCF share a secret key KHS; the UE and the HSS generate random numbers respectively; synchronizing a system clock; the UE trust the HSS to which the UE belongs; and realizing UE registration authentication and key agreement as well as service authentication and key agreement based on the content. False base station attacks, fake user network access, replay attacks, man-in-the-middle attacks and shared key leakage can be avoided, fake users enjoy encrypted communication, and network end expenses are saved. 本发明公开了一种均衡安全和效率的改进型5G消息RCS接入鉴权IMS-AKA机制，该机制中，UE与HSS共享密钥生成函数f3、f4和f5及消息鉴权函数H1；UE与S-CSCF共享密钥生成函数f3'、f4'及消息鉴权函数H2；HSS与S-CSCF共享密钥KHS；UE和HSS