Section: 5.4.1.3.4 Authentication completion by the network
Content: Upon receipt of an AUTHENTICATION RESPONSE message, the network stops the timer T3560 and checks the correctness of RES* (see 3GPP TS 33.501[ Security architecture and procedures for 5G System ]  [24]). If the 5G AKA based primary authentication and key agreement procedure has been completed successfully and the related ngKSI is stored in the 5G NAS security context of the network, the network shall include a different ngKSI value in the AUTHENTICATION REQUEST message when it initiates a new 5G AKA based primary authentication and key agreement procedure. Upon receipt of an AUTHENTICATION FAILURE message, the network stops the timer T3560. In the case where the 5GMM cause #21 "synch failure" is received, the core network may renegotiate with the UDM/AUSF and provide the UE with new authentication parameters.