Content for  TS 38.473  Word version:  18.2.0

The purpose of the gNB-DU Configuration Update procedure is to update application level configuration data needed for the gNB-DU and the gNB-CU to interoperate correctly on the F1 interface. This procedure does not affect existing UE-related contexts, if any. The procedure uses non-UE associated signalling.

The gNB-DU initiates the procedure by sending a GNB-DU CONFIGURATION UPDATE message to the gNB-CU including an appropriate set of updated configuration data that it has just taken into operational use. The gNB-CU responds with GNB-DU CONFIGURATION UPDATE ACKNOWLEDGE message to acknowledge that it successfully updated the configuration data. If an information element is not included in the GNB-DU CONFIGURATION UPDATE message, the gNB-CU shall interpret that the corresponding configuration data is not changed and shall continue to operate the F1-C interface with the existing related configuration data. The updated configuration data shall be stored in both nodes and used as long as there is an operational TNL association or until any further update is performed. If gNB-DU ID IE is contained in the GNB-DU CONFIGURATION UPDATE message for a newly established SCTP association, the gNB-CU will associate this association with the related gNB-DU. If Served Cells To Add Item IE is contained in the GNB-DU CONFIGURATION UPDATE message, the gNB-CU shall add cell information according to the information in the Served Cell Information IE. For NG-RAN, the gNB-DU shall include the gNB-DU System Information IE. If Served Cells To Modify Item IE is contained in the GNB-DU CONFIGURATION UPDATE message, the gNB-CU shall modify information of cell indicated by Old NR CGI IE according to the information in the Served Cell Information IE and overwrite the served cell information for the affected served cell. Further, if the gNB-DU System Information IE is present the gNB-CU shall store and replace any previous information received. If Served Cells To Delete Item IE is contained in the GNB-DU CONFIGURATION UPDATE message, the gNB-CU shall delete information of cell indicated by Old NR CGI IE. If Cells Status Item IE is contained in the GNB-DU CONFIGURATION UPDATE message, the gNB-CU shall update the information about the cells, as described in TS 38.401. If the Switching Off Ongoing IE is present in the Cells Status Item IE, contained in the GNB-DU CONFIGURATION UPDATE message, and the corresponding Service State IE is set to "Out-of-Service", the gNB-CU shall ignore the Switching Off Ongoing IE. If Cells to be Activated List Item IE is contained in the GNB-DU CONFIGURATION UPDATE ACKNOWLEDGE message, the gNB-DU shall activate the cell indicated by NR CGI IE and reconfigure the physical cell identity for cells for which the NR PCI IE is included. If Cells to be Activated List Item IE is contained in the GNB-DU CONFIGURATION UPDATE ACKNOWLEDGE message and the indicated cells are already activated, the gNB-DU shall update the cell information received in Cells to be Activated List Item IE. If Cells to be Activated List Item IE is included in the GNB-DU CONFIGURATION UPDATE ACKNOWLEDGE message, and the information for the cell indicated by the NR CGI IE includes the IAB Info IAB-donor-CU IE, the gNB-DU shall, if supported, apply the IAB STC Info IE therein to the indicated cell. If Cells to be Deactivated List Item IE is contained in the GNB-DU CONFIGURATION UPDATE ACKNOWLEDGE message, the gNB-DU shall deactivate all the cells with NR CGI listed in the IE. If Dedicated SI Delivery Needed UE List IE is contained in the GNB-DU CONFIGURATION UPDATE message, the gNB-CU should take it into account when informing the UE of the updated system information via the dedicated RRC message. For NG-RAN, the gNB-CU shall include the gNB-CU System Information IE in the GNB-DU CONFIGURATION UPDATE ACKNOWLEDGE message. The SIB type to Be Updated List IE shall contain the full list of SIBs to be broadcast. For NG-RAN, the gNB-DU may include the RAN Area Code IE in the GNB-DU CONFIGURATION UPDATE message. The gNB-CU shall store and replace any previously provided RAN Area Code IE by the received RAN Area Code IE. For NG-RAN, the gNB-DU may include the Supported MBS FSA ID List IE in the Served Cell Information IE in the GNB-DU CONFIGURATION UPDATE message. The gNB-CU shall store and replace any previously provided MBS FSA ID list IE by the received MBS FSA ID list IE. If Available PLMN List IE, and optionally also Extended Available PLMN List IE, is contained in GNB-DU CONFIGURATION UPDATE ACKNOWLEDGE message, the gNB-DU shall overwrite the whole available PLMN list and update the corresponding system information. If Available SNPN ID List IE is contained in GNB-DU CONFIGURATION UPDATE ACKNOWLEDGE message, the gNB-DU shall overwrite the whole available SNPN ID list and update the corresponding system information. If in GNB-DU CONFIGURATION UPDATE message, the Cell Direction IE is present, the gNB-CU should use it to understand whether the cell is for UL or DL only. If in GNB-DU CONFIGURATION UPDATE message, the Cell Direction IE is omitted in the Served Cell Information IE it shall be interpreted as that the Cell Direction is Bi-directional. If the GNB-DU CONFIGURATION UPDATE message includes gNB-DU TNL Association To Remove List IE, the gNB-CU shall, if supported, initiate removal of the TNL association(s) indicated by gNB-DU TNL endpoint(s) and gNB-CU TNL endpoint(s) if the TNL Association Transport Layer Address gNB-CU IE is present, or the TNL association(s) indicated by gNB-DU TNL endpoint(s) if the TNL Association Transport Layer Address gNB-CU IE is absent:

• if the received TNL Association Transport Layer Address IE includes the Port Number IE, the gNB-DU TNL endpoint is identified by the Endpoint IP Address IE and the Port Number IE. Otherwise, the gNB-DU TNL endpoints correspond to all gNB-DU TNL endpoints identified by the Endpoint IP Address IE and any port number(s).
• if the received TNL Association Transport Layer Address gNB-CU IE includes the Port Number IE, the gNB-CU TNL endpoint is identified by the Endpoint IP Address IE and the Port Number IE. Otherwise, the gNB-CU TNL endpoints correspond to all gNB-CU TNL endpoints identified by the Endpoint IP Address IE and any port number(s).

If the Intended TDD DL-UL Configuration IE is present in the GNB-DU CONFIGURATION UPDATE message, the receiving gNB-CU shall use the received information for Cross Link Interference management and/or NR-DC power coordination. The gNB-CU may merge the Intended TDD DL-UL Configuration information received from two or more gNB-DUs. The gNB-CU shall consider the received Intended TDD DL-UL Configuration IE content valid until reception of an update of the IE for the same cell(s). If the Aggressor gNB Set ID IE is included in the Served Cell Information IE in the GNB-DU CONFIGURATION UPDATE message, the gNB-CU shall, if supported, take it into account. If the Victim gNB Set ID IE is included in the Served Cell Information IE in the GNB-DU CONFIGURATION UPDATE message, the gNB-CU shall, if supported, take it into account. If the GNB-DU CONFIGURATION UPDATE message includes Transport Layer Address Info IE, the gNB-CU shall, if supported, take into account for IPSec tunnel establishment. If the GNB-DU CONFIGURATION UPDATE ACKNOWLEDGE message includes Transport Layer Address Info IE, the gNB-DU shall, if supported, take into account for IPSec tunnel establishment. If the GNB-DU CONFIGURATION UPDATE ACKNOWLEDGE message contains the Uplink BH Non-UP Traffic Mapping IE, the gNB-DU shall, if supported, consider the information therein for mapping of non-UP uplink traffic. If the SFN Offset IE is contained in the Served Cell Information IE in GNB-DU CONFIGURATION UPDATE message, the gNB-CU shall, if supported, use this information to deduce the SFN0 offset of the reported cell. If the NR PRACH Configuration List IE is included in the Served Cell Information IE contained in the GNB-DU CONFIGURATION UPDATE message, the gNB-CU may store the information, and forward it to other RAN nodes for RACH optimisation. If the L139 Info IE included in the NR PRACH Configuration List IE is present, it shall contain the Root Sequence Index IE. If the GNB-DU CONFIGURATION UPDATE ACKNOWLEDGE message contains the BAP Address IE, the gNB-DU shall, if supported, store the received BAP address and use it as specified in TS 38.340. If the Coverage Modification Notification IE is contained in the GNB-DU CONFIGURATION UPDATE message, the gNB-CU shall, if supported, take it into account for Coverage and Capacity Optimization and network energy saving. If the Coverage Modification Cause IE is set to the "network energy saving", gNB-CU may consider those deactivated SSB beams are due to network energy saving. If the Cells for SON IE is present in the GNB-DU CONFIGURATION UPDATE ACKNOWLEDGE message, the gNB-DU may store or update this information and behaves as follows:

• For each served cell indicated by the NR CGI IE included within the Cells for SON Item IE, the gNB-DU may adjust the PRACH configuration of this served cell.
• If the Neighbour NR Cells for SON List IE is present in the Cells for SON Item IE, the gNB-DU may take the PRACH configuration of neighbour cells included in the Neighbour NR Cells for SON List IE into consideration when adjusting the PRACH configuration of the served cell.

If the RedCap Broadcast Information IE is contained in the Served Cell Information IE in the GNB-DU CONFIGURATION UPDATE message, the gNB-CU may store and use this information to determine a suitable target in case of subsequent outgoing mobility involving RedCap UEs. If the eRedCap Broadcast Information IE is contained in the Served Cell Information IE in the GNB-DU CONFIGURATION UPDATE message, the gNB-CU may store and use this information to determine a suitable target in case of subsequent outgoing mobility involving eRedCap UEs. If the TAI NSAG Support List IE is included in the Served Cell Information IE in the GNB-DU CONFIGURATION UPDATE message, the gNB-CU shall, if supported, use this information as specified in TS 23.501. If the gNB-DU Name IE is included in the GNB-DU CONFIGURATION UPDATE message, the gNB-CU may store it or update this IE value if already stored, and use it as a human readable name of the gNB-DU. If the Extended gNB-DU Name IE is included in the GNB-DU CONFIGURATION UPDATE message, the gNB-CU may store it or update this IE value if already stored, and use it as a human readable name of the gNB-DU and shall ignore the gNB-DU Name IE if also included. If the RRC Terminating IAB-Donor Related Info IE is included in the GNB-DU CONFIGURATION UPDATE message, the gNB-CU shall, if supported, consider that the BAP address indicated by the Mobile IAB-MT BAP Address IE is assigned by the gNB-CU of the RRC-terminating IAB-donor indicated by the RRC Terminating IAB-Donor gNB-ID IE, and it shall use this BAP address and gNB ID for the subsequent IAB Transport Migration Management procedure towards the RRC-terminating IAB-donor of the mobile IAB-node as needed, as specified in TS 38.423. If the GNB-DU CONFIGURATION UPDATE message contains the Mobile IAB-MT User Location Information IE, the gNB-CU shall, if supported, take it into account when reporting UE location information to the AMF for a UE served by the mobile IAB-node. If the XR Broadcast Information IE is included in the Served Cell Information IE in the GNB-DU CONFIGURATION UPDATE message, the gNB-CU shall, if supported, consider the indicated cell does not allow 2Rx XR UEs in case of subsequent outgoing mobility involving XR UEs.

If the gNB-CU cannot accept the update, it shall respond with a GNB-DU CONFIGURATION UPDATE FAILURE message and appropriate cause value. If the GNB-DU CONFIGURATION UPDATE FAILURE message includes the Time To Wait IE, the gNB-DU shall wait at least for the indicated time before reinitiating the GNB-DU CONFIGURATION UPDATE message towards the same gNB-CU.

Not applicable.

The purpose of the gNB-CU Configuration Update procedure is to update application level configuration data needed for the gNB-DU and gNB-CU to interoperate correctly on the F1 interface. This procedure does not affect existing UE-related contexts, if any. The procedure uses non-UE associated signalling.

The gNB-CU initiates the procedure by sending a GNB-CU CONFIGURATION UPDATE message including the appropriate updated configuration data to the gNB-DU. The gNB-DU responds with a GNB-CU CONFIGURATION UPDATE ACKNOWLEDGE message to acknowledge that it successfully updated the configuration data. If an information element is not included in the GNB-CU CONFIGURATION UPDATE message, the gNB-DU shall interpret that the corresponding configuration data is not changed and shall continue to operate the F1-C interface with the existing related configuration data. The updated configuration data shall be stored in the respective node and used as long as there is an operational TNL association or until any further update is performed. If Cells to be Activated List Item IE is contained in the GNB-CU CONFIGURATION UPDATE message, the gNB-DU shall activate the cell indicated by NR CGI IE and reconfigure the physical cell identity for which the NR PCI IE is included. If the SSBs within the cell to be Activated List IE is included in the Cells to be Activated List Item IE within the gNB-CU CONFIGURATION UPDATE message, the gNB-DU shall, if supported, only activate those SSB beams indicated by the SSB Index IE. If at least one requested SSB beam in the SSBs within the cell to be Activated List IE is activated, the gNB-DU includes the Cells with SSBs Activated List IE in the GNB-CU CONFIGURATION UPDATE ACKNOWLEDGE message. The gNB-CU shall consider that the SSB beams indicated by the SSBs activated List IE as activated. If Cells to be Deactivated List Item IE is contained in the GNB-CU CONFIGURATION UPDATE message, the gNB-DU shall deactivate the cell indicated by NR CGI IE. If Cells to be Activated List Item IE is contained in the GNB-CU CONFIGURATION UPDATE message and the indicated cells are already activated, the gNB-DU shall update the cell information received in Cells to be Activated List Item IE. If Cells to be Activated List Item IE is included in the GNB-CU CONFIGURATION UPDATE message, and the information for the cell indicated by the NR CGI IE includes the IAB Info IAB-donor-CU IE, the gNB-DU shall, if supported, apply the IAB STC Info IE therein to the indicated cell. If the Cells Allowed to be Deactivated List IE is contained in the GNB-CU CONFIGURATION UPDATE message, the gNB-DU shall, if supported, consider that it is allowed to deactivate the SSB beams within the indicated cells for network energy saving purpose. If the gNB-CU System Information IE is contained in the gNB-CU CONFIGURATION UPDATE message, the gNB-DU shall include the Dedicated SI Delivery Needed UE List IE in the GNB-CU CONFIGURATION UPDATE ACKNOWLEDGE message for UEs that are unable to receive system information from broadcast. If Dedicated SI Delivery Needed UE List IE is contained in the GNB-CU CONFIGURATION UPDATE ACKNOWLEDGE message, the gNB-CU should take it into account when informing the UE of the updated system information via the dedicated RRC message. If the gNB-CU TNL Association To Add List IE is contained in the gNB-CU CONFIGURATION UPDATE message, the gNB-DU shall, if supported, use it to establish the TNL association(s) with the gNB-CU. If the gNB-CU TNL Association To Add List IE is included in the GNB-CU CONFIGURATION UPDATE message, and if the TNL Association Transport Layer Information IE does not include the Port Number IE, the gNB-DU shall assume that port number value 38472 is used for the endpoint. The gNB-DU shall report to the gNB-CU, in the gNB-CU CONFIGURATION UPDATE ACKNOWLEDGE message, the successful establishment of the TNL association(s) with the gNB-CU as follows:

• A list of TNL address(es) with which the gNB-DU successfully established the TNL association shall be included in the gNB-CU TNL Association Setup List IE;
• A list of TNL address(es) with which the gNB-DU failed to establish the TNL association shall be included in the gNB-CU TNL Association Failed To Setup List IE.

If the GNB-CU CONFIGURATION UPDATE message includes gNB-CU TNL Association To Remove List IE, the gNB-DU shall, if supported, initiate removal of the TNL association(s) indicated by gNB-CU TNL endpoint(s) and gNB-DU TNL endpoint(s) if the TNL Association Transport Layer Address gNB-DU IE is present, or the TNL association(s) indicated by gNB-CU TNL endpoint(s) if the TNL Association Transport Layer Address gNB-DU IE is absent:

• if the received TNL Association Transport Layer Address IE includes the Port Number IE, the gNB-CU TNL endpoint is identified by the Endpoint IP Address IE and the Port Number IE. Otherwise, the gNB-CU TNL endpoints correspond to all gNB-CU TNL endpoints identified by the Endpoint IP Address IE and any port number(s).
• if the received TNL Association Transport Layer Address gNB-DU IE includes the Port Number IE, the gNB-DU TNL endpoint is identified by the Endpoint IP Address IE and the Port Number IE. Otherwise, the gNB-DU TNL endpoints correspond to all gNB-DU node TNL endpoints identified by the Endpoint IP Address IE and any port number(s).

If the gNB-CU TNL Association To Update List IE is contained in the gNB-CU CONFIGURATION UPDATE message the gNB-DU shall, if supported, overwrite the previously stored information for the related TNL Association(s).

• if the received TNL Association Transport Layer Address IE includes the Port Number IE, the gNB-CU TNL endpoint is identified by the Endpoint IP Address IE and the Port Number IE. Otherwise, the gNB-CU TNL endpoints correspond to all gNB-CU TNL endpoints identified by the Endpoint IP Address IE and any port number(s).

If in the gNB-CU CONFIGURATION UPDATE message the TNL Association usage IE is included in the gNB-CU TNL Association To Add List IE or the gNB-CU TNL Association To Update List IE, the gNB-DU node shall, if supported, use it as described in TS 38.472. For NG-RAN, the gNB-CU shall include the gNB-CU System Information IE in the GNB-CU CONFIGURATION UPDATE message. The SIB type to Be Updated List IE shall contain the full list of SIBs to be broadcast. If Protected E-UTRA Resources List IE is contained in the GNB-CU CONFIGURATION UPDATE message, the gNB-DU shall protect the corresponding resource of the cells indicated by E-UTRA Cells List IE for spectrum sharing between E-UTRA and NR. If the GNB-CU CONFIGURATION UPDATE message contains the Protected E-UTRA Resource Indication IE, the receiving gNB-DU should forward it to lower layers and use it for cell-level resource coordination. The gNB-DU shall consider the received Protected E-UTRA Resource Indication IE when expressing its desired resource allocation during gNB-DU Resource Coordination procedure. The gNB-DU shall consider the received Protected E-UTRA Resource Indication IE content valid until reception of a new update of the IE for the same gNB-DU. If Available PLMN List IE, and optionally also Extended Available PLMN List IE, is contained in GNB-CU CONFIGURATION UPDATE message, the gNB-DU shall overwrite the whole available PLMN list and update the corresponding system information. If Available SNPN ID List IE is contained in GNB-CU CONFIGURATION UPDATE message, the gNB-DU shall overwrite the whole available SNPN ID list and update the corresponding system information. If Cells Failed to be Activated Item IE is contained in the GNB-CU CONFIGURATION UPDATE ACKNOWLEDGE message, the gNB-CU shall consider that the indicated cells are out-of-service as defined in TS 38.401. If the Neighbour Cell Information List IE is present in the GNB-CU CONFIGURATION UPDATE message, the receiving gNB-DU shall use the received information for Cross Link Interference management and/or NR-DC power coordination. The gNB-DU shall consider the received Neighbour Cell Information List IE content valid until reception of an update of the IE for the same cell(s). If the Intended TDD DL-UL Configuration NR IE is absent from the Neighbour Cell Information List IE, whereas the corresponding NR CGI IE is present, the receiving gNB-DU shall remove the previously stored Neighbour Cell Information IE corresponding to the NR CGI. If the GNB-CU CONFIGURATION UPDATE message includes Transport Layer Address Info IE, the gNB-DU shall, if supported, take into account for IPSec tunnel establishment. If the GNB-CU CONFIGURATION UPDATE ACKNOWLEDGE message includes Transport Layer Address Info IE, the gNB-CU shall, if supported, take into account for IPSec tunnel establishment. If the GNB-CU CONFIGURATION UPDATE message contains the Uplink BH Non-UP Traffic Mapping IE, the gNB-DU shall, if supported, consider the information therein for mapping of non-UP uplink traffic. If the IAB Barred IE is included in the GNB-CU CONFIGURATION UPDATE message, the gNB-DU shall, if supported, consider it as an indication of whether the cell allows IAB-node access or not. If the BAP Address IE is included in the GNB-CU CONFIGURATION UPDATE message, the gNB-DU shall, if supported, store the received BAP address and use it as specified in TS 38.340. If the CCO Assistance Information IE is contained in the GNB-CU CONFIGURATION UPDATE message, and the NR CGI IE contained in the Affected Cells and Beams IE is served by the gNB-DU, the gNB-DU may use it to determine a new cell and/or beam configuration. If the CCO Assistance Information IE is contained in the GNB-CU CONFIGURATION UPDATE message and the NR CGI IE contained in the Affected Cells and Beams IE is not served by the gNB-DU, the gNB-DU may use it to adjust coverage of its cells.If the CCO issue detection IE set to "network energy saving" is included in the CCO Assistance Information IE, the gNB-DU may consider the indicated SSB beams by the Affected Cells and Beam IE are deactivated due to network energy saving. If the Cells for SON IE is present in the GNB-CU CONFIGURATION UPDATE message, the gNB-DU may store or update this information and it behaves as follows:

• For each served cell indicated by the NR CGI IE included within the Cells for SON Item IE, the gNB-DU may adjust the PRACH configuration of this served cell.
• If the Neighbour NR Cells for SON List IE is present in the Cells for SON Item IE, the gNB-DU may take the PRACH configuration of neighbour cells included in the Neighbour NR Cells for SON List IE into consideration when adjusting the PRACH configuration of the served cell.

If the gNB-CU Name IE is included in the GNB-CU CONFIGURATION UPDATE message, the gNB-DU may store it or update this IE value if already stored, and use it as a human readable name of the gNB-CU. If the Extended gNB-CU Name IE is included in the GNB-CU CONFIGURATION UPDATE message, the gNB-DU may store it or update this IE value if already stored, and use it as a human readable name of the gNB-CU and shall ignore the gNB-CU Name IE if also included. If the Mobile IAB Barred IE is included in the GNB-CU CONFIGURATION UPDATE message, the gNB-DU shall, if supported, consider it as an indication of whether the cell allows mobile IAB-node access.

If the gNB-DU cannot accept the update, it shall respond with a GNB-CU CONFIGURATION UPDATE FAILURE message and appropriate cause value. If the GNB-CU CONFIGURATION UPDATE FAILURE message includes the Time To Wait IE, the gNB-CU shall wait at least for the indicated time before reinitiating the GNB-CU CONFIGURATION UPDATE message towards the same gNB-DU.

Not applicable.