Message Dictionary (Message)¶
A dictionary for looking up 5GC signaling Messages by their Protocol, direction, purpose, and main IEs. It covers the main Messages that appear in the Registration chapter.
Related: Protocol Dictionary / Timer Dictionary / Cause Dictionary
Message List¶
| Message | Protocol | Direction | Purpose (1 line) | Main IEs | Related Chapter/Spec |
|---|---|---|---|---|---|
| Registration Request | NAS (5GMM) | UE→AMF | Registration request | 5GS registration type, 5GS mobile identity (SUCI / 5G-GUTI), UE security capability | Registration / TS 24.501 §8.2.6 |
| Registration Accept | NAS (5GMM) | AMF→UE | Registration acceptance | 5G-GUTI, allowed NSSAI, registration result | Registration / TS 24.501 §8.2.7 |
| Registration Complete | NAS (5GMM) | UE→AMF | Registration completion | (ACK on 5G-GUTI reassignment, etc.) | Registration / TS 24.501 §8.2.8 |
| Authentication Request | NAS (5GMM) | AMF→UE | Sending the authentication challenge | ABBA, RAND, AUTN | Registration / TS 24.501 §8.2.1 |
| Authentication Response | NAS (5GMM) | UE→AMF | Authentication response | RES* | Registration / TS 24.501 §8.2.2 |
| Security Mode Command | NAS (5GMM) | AMF→UE | Instruction to establish NAS security | selected NAS security algorithms | Registration / TS 24.501 §8.2.25 |
| Security Mode Complete | NAS (5GMM) | UE→AMF | Completion of NAS security establishment | (IMEISV, etc., as needed) | Registration / TS 24.501 §8.2.26 |
| NG Setup Request | NGAP | gNB→AMF | Request to establish N2 (NG-C) | Global RAN Node ID, Supported TA List | Registration / TS 38.413 §9.2.6 |
| NG Setup Response | NGAP | AMF→gNB | N2 establishment response | AMF Name, Served GUAMI List, PLMN Support List | Registration / TS 38.413 §9.2.6 |
| Initial UE Message | NGAP | gNB→AMF | Carries the NAS of the initial UE | NAS-PDU, RAN UE NGAP ID, User Location Information | Registration / TS 38.413 §9.2.5.1 |
| Initial Context Setup Request | NGAP | AMF→gNB | Request to establish UE context | AMF UE NGAP ID, GUAMI, Allowed NSSAI, Security Key | Registration / TS 38.413 §9.2.2.1 |
| Initial Context Setup Response | NGAP | gNB→AMF | UE context establishment response | (result reporting IEs) | Registration / TS 38.413 §9.2.2.2 (to be confirmed: clause number) |
About Clause Numbers To Be Confirmed
NG Setup Request/Response are defined within the same clause (TS 38.413 §9.2.6). The clause number of Initial Context Setup Response (§9.2.2.2) is treated as to be confirmed, avoiding a definitive assertion. The listing of IEs is representative, not exhaustive.