 XRES* and verifies the identity. 16. The AUSF sends an authentication response with SUPI and Kseaf to the AMF. The AMF sends Kamf from Kseaf. 17. The AUSF sends authentication confirmation to UDM on successful verification. 18. The UDM responds with an acknowledgment to the AUSF. 5G Standalone Networks UE Performs Registration: Authentication + AMF reg in UDM (3 of 5) AM PCF DL NAS Transport NAS: SMC (Selected Sec. Algos, DL Info Transport UE Security Capability, ngKSI ME Check IP Start Start UL Deciphen Slice Select UL Ciphering AM Data SM Data UL Info Tansport UE CNTX in Subscriber UE Cntx Event UL NAS Xport UE Authn Data Mgmt Notify NAS: SMC Accept Start DL Cipher NAS Ciphering & Intgrt Prot Setup Select UDM UE_CM Registration Request (SUPI, AMF 3gpp Acess, AMF ID) UE_CM Registration Response UE Subscriber Data Mgmt Get (SUPI, AM Data, SMF Select Data, UE Cntx in SMF) UE Subscriber Data Mgmt Get Resp (Access & Mobility Subscription data, SMF Selection Subscription data Subscribe to Data Change Notifications (SUPI) Subscription Ack DL NAS Transport NAS: Request IMEI DL Info Transport UL Info Tansport Equipment Identity Respository UL NAS Xport NAS: IMEI Equipment Identity Check Integrity Protected Msg Int. Protect & Ciphered Figure 11.6 - UE registration - part 3: authentication and AMF registration 5G SA network design fundamentals 19. A DL NAS Transport message is then sent from the AMF to the gNB. 20. The NAS message carrying the selected security algorithm, UE security capability, and more are sent to the UE. 21. A UL Information Transport Message is then sent to the gNB to be sent to the AMF; this contains the Security mode command Accept message. 22. The UL NAS transport message is sent to the AMF and the DL Cipher starts. The AMF selects the UDM. 23. The AMF sends the UE_CM registration request to the UDM. This contains the SUPI, AMF 3GPP Access, and AMF ID. The UDM checks the UE authentication. 24. The UDM sends the UE_CM registration response to the AMF. 25. The AMF sends a UE subscriber Data Manageme