School of Specs 38.300v19.3.0

3GPP 38.300 v19.3.0 — the document's own text

15.3.1.3 Application layer initialization

Taught in 13. Where RAN meets the groups that write the rest of 3GPP (TSG RAN — the group that specifies the radio, in depth).

Once SCTP connectivity has been established, the NG-RAN node and the AMF shall exchange application level configuration data over NGAP with the NG Setup procedure, which is needed for these two nodes to interwork correctly on the NG interface:

  • The NG-RAN node provides the relevant configuration information to the AMF, which includes list of supported TA(s), etc.;
  • The AMF provides the relevant configuration information to the NG-RAN node, which includes PLMN ID, etc.;
  • When the application layer initialization is successfully concluded, the dynamic configuration procedure is completed and the NG-C interface is operational.

After the application layer initialization is successfully completed, the AMF may add or update or remove SCTP endpoints to be used for NG-C signalling between the AMF and the NG-RAN node pair as specified in TS 23.501 [3].

The AMF and the NG-RAN node may agree at the NG Setup procedure that UE-related contexts and related signalling connection that have been existing before the NG Setup shall not be affected. The AMF or NG-RAN node or both may trigger an NGAP Reset procedure for any UE-related context and related signalling connection for UEs which could not be kept in CM_CONNECTED mode, or for UEs for which the AMF or the NG-RAN node decided to remove the UE context and related signalling connection. If either the AMF or the NG-RAN node do not agree to keep the UE contexts (if any), then they are removed and all related signalling connections are erased.