Content for  TS 37.483  Word version:  18.2.0

The purpose of the gNB-CU-UP Configuration Update procedure is to update application level configuration data needed for the gNB-CU-UP and the gNB-CU-CP to interoperate correctly on the E1 interface. This procedure does not affect existing UE-related contexts, if any. The procedure uses non-UE associated signalling.

The gNB-CU-UP initiates the procedure by sending a GNB-CU-UP CONFIGURATION UPDATE message to the gNB-CU-CP including an appropriate set of updated configuration data that it has just taken into operational use. The gNB-CU-CP responds with GNB-CU-UP CONFIGURATION UPDATE ACKNOWLEDGE message to acknowledge that it successfully updated the configuration data. If an information element is not included in the GNB-CU-UP CONFIGURATION UPDATE message, the gNB-CU-CP shall interpret that the corresponding configuration data is not changed and shall continue to operate with the existing related configuration data. If the Supported PLMNs IE is included in the GNB-CU-UP CONFIGURATION UPDATE message, the gNB-CU-CP shall overwrite the whole list of information and store the corresponding information.

• If the Slice Support List IE is contained in the GNB-CU-UP CONFIGURATION UPDATE message, the gNB-CU-CP shall store the corresponding information and replace any existing information.
• If the NR CGI Support List or the Extended NR CGI Extended Support List IE is contained in the GNB-CU-UP CONFIGURATION UPDATE message, the gNB-CU-CP shall store the corresponding information and replace any existing information.
• If the ECGI Support List IE is contained in the GNB-CU-UP CONFIGURATION UPDATE message, the gNB-CU-CP shall store the corresponding information and replace any existing information.
• If the QoS Parameters Support List IE is contained in the GNB-CU-UP CONFIGURATION UPDATE message, the gNB-CU-CP shall store the corresponding information and replace any existing information.
• If the NPN Support Information IE is contained in the GNB-CU-UP CONFIGURATION UPDATE message, the gNB-CU-CP shall store the corresponding information and replace any existing information.

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 the gNB-CU-UP Capacity IE is contained in the GNB-CU-UP CONFIGURATION UPDATE message, the gNB-CU-CP shall take this IE into account. If the gNB-CU-UP ID IE is included in the GNB-CU-UP CONFIGURATION UPDATE message, the gNB-CU-CP shall associate the TNLA to the E1 interface instance using the gNB-CU-UP ID. If the gNB-CU-UP Name IE is included in the GNB-CU-UP CONFIGURATION UPDATE message, the gNB-CU-CP may store it or update this IE value if already stored, and use it as a human readable name of the gNB-CU-UP. If the Extended gNB-CU-UP Name IE is included in the GNB-CU-UP CONFIGURATION UPDATE message, the gNB-CU-CP may store it or update this IE value if already stored, and use it as a human readable name of the gNB-CU-UP and shall ignore the gNB-CU-UP Name IE if also included. If the GNB-CU-UP CONFIGURATION UPDATE message includes gNB-CU-UP TNLA To Remove List IE, the gNB-CU-CP shall, if supported, initiate removal of the TNL association(s) indicated by gNB-CU-CP TNL endpoint(s) and gNB-CU-UP TNL endpoint(s) if the TNLA Transport Layer Address gNB-CU-CP IE is present, or the TNL association(s) indicated by gNB-CU-UP TNL endpoint(s) if the TNLA Transport Layer Address gNB-CU-CP IE is absent:

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

If the GNB-CU-UP CONFIGURATION UPDATE message includes the Transport Network Layer Address Info IE, the gNB-CU-CP shall, if supported, take this IE into account for IPSec tunnel establishment. If the GNB-CU-UP CONFIGURATION UPDATE ACKNOWLEDGE message includes the Transport Network Layer Address Info IE, the gNB-CU-UP shall, if supported, take this IE into account for IPSec tunnel establishment.

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

Not applicable.

The purpose of the gNB-CU-CP Configuration Update procedure is to update application level configuration data needed for the gNB-CU-CP and the gNB-CU-UP to interoperate correctly on the E1 interface. This procedure does not affect existing UE-related contexts, if any. The procedure uses non-UE associated signalling.

The gNB-CU-CP initiates the procedure by sending a GNB-CU-CP CONFIGURATION UPDATE message to the gNB-CU-UP including an appropriate set of updated configuration data that it has just taken into operational use. The gNB-CU-UP responds with GNB-CU-CP CONFIGURATION UPDATE ACKNOWLEDGE message to acknowledge that it successfully updated the configuration data. If an information element is not included in the GNB-CU-CP CONFIGURATION UPDATE message, the gNB-CU-UP shall interpret that the corresponding configuration data is not changed and shall continue to operate 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 the gNB-CU-CP Name IE is included in the GNB-CU-CP CONFIGURATION UPDATE message, the gNB-CU-UP may store it or update this IE value if already stored, and use it as a human readable name of the gNB-CU-CP. If the Extended gNB-CU-CP Name IE is included in the GNB-CU-CP CONFIGURATION UPDATE message, the gNB-CU-UP may store it or update this IE value if already stored, and use it as a human readable name of the gNB-CU-CP and shall ignore the gNB-CU-CP Name IE if also included. If the gNB-CU-CP TNLA To Add List IE is contained in the gNB-CU-CP CONFIGURATION UPDATE message, the gNB-CU-UP shall, if supported, use it to establish the TNL association(s) with the gNB-CU-CP. If the gNB-CU-CP TNLA To Add List IE is included in the gNB-CU-CP CONFIGURATION UPDATE message, and if the gNB-CU-CP TNLA To Add List IE does not include the Port Number IE, the gNB-CU-UP shall assume that port number value 38462 is used for the endpoint. The gNB-CU-UP shall report to the gNB-CU-CP, in the gNB-CU-CP CONFIGURATION UPDATE ACKNOWLEDGE message, the successful establishment of the TNL association(s) with the gNB-CU-CP as follows:

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

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

• if the received TNLA Transport Layer Address IE includes the Port Number IE, the gNB-CU-CP TNL endpoint is identified by the Endpoint IP Address IE and the Port Number IE. Otherwise, the gNB-CU-CP TNL endpoints correspond to all gNB-CU-CP TNL endpoints identified by the Endpoint IP Address IE and any Port Number(s).
• if the received TNLA Transport Layer Address gNB-CU-UP IE includes the Port Number IE, the gNB-CU-UP TNL endpoint is identified by the Endpoint IP Address IE and the Port Number IE. Otherwise, the gNB-CU-UP TNL endpoints correspond to all gNB-CU-UP TNL endpoints identified by the Endpoint IP Address IE and any Port Number(s).If the gNB-CU-CP TNLA To Update List IE is contained in the gNB-CU-CP CONFIGURATION UPDATE message the gNB-CU-UP shall, if supported, overwrite the previously stored information for the related TNL association.
• If the received TNLA Transport Layer Address IE includes the Port Number IE, the gNB-CU-CP TNL endpoint is identified by the Endpoint IP Address IE and the Port Number IE. Otherwise, the gNB-CU-CP TNL endpoints correspond to all gNB-CU-CP TNL endpoints identified by the Endpoint IP Address IE and any Port Number(s).

If the TNLA Usage IE is included in the gNB-CU-CP TNLA To Add List IE or the gNB-CU-CP TNLA To Update List IE in the gNB-CU-CP CONFIGURATION UPDATE message, the gNB-CU-UP shall, if supported, use it as described in TS 37.482. If the GNB-CU-CP CONFIGURATION UPDATE message includes the Transport Network Layer Address Info IE, the gNB-CU-UP shall, if supported, take this IE into account for IPSec tunnel establishment. If the GNB-CU-CP CONFIGURATION UPDATE ACKNOWLEDGE message includes the Transport Network Layer Address Info IE, the gNB-CU-CP shall, if supported, take this IE into account for IPSec tunnel establishment.

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

Not applicable.

The purpose of the E1 Release procedure is to release all existing signalling connections and related application level data. This procedure does not affect existing UE-related contexts, if any. The procedure uses non-UE associated signalling.

Not applicable.

The purpose of the gNB-CU-UP Status Indication procedure is to inform the gNB-CU-CP that the gNB-CU-UP is overloaded so that overload reduction actions can be applied. The procedure uses non-UE associated signalling.

The gNB-CU-UP initiates the procedure by sending the GNB-CU-UP STATUS INDICATION message to the gNB-CU-CP. If the gNB-CU-UP Overload Information IE in the GNB-CU-UP STATUS INDICATION message indicates that the gNB-CU-UP is overloaded, the gNB-CU-CP shall apply overload reduction actions until informed, with a new GNB-CU-UP STATUS INDICATION message, that the overload situation has ceased. The detailed overload reduction policy is up to gNB-CU-CP implementation.

Not applicable.

This procedure is used by an gNB-CU-CP to request the reporting of load measurements to gNB-CU-UP. The procedure uses non UE-associated signalling.

The procedure is initiated with a RESOURCE STATUS REQUEST message sent from gNB-CU-CP to gNB-CU-UP to start a measurement or stop a measurements. If gNB-CU-UP is capable to provide all requested resource status information, it shall initiate the measurement as requested by gNB-CU-CP, and respond with the RESOURCE STATUS RESPONSE message. Interaction with other procedures When starting a measurement, the Report Characteristics IE in the RESOURCE STATUS REQUEST indicates the type of objects gNB-CU-UP shall perform measurements on. The gNB-CU-UP shall include in the RESOURCE STATUS UPDATE message:

• the HW Capacity Indicator IE, if the second bit, "HW Capacity Ind Periodic" of the Report Characteristics IE included in the RESOURCE STATUS REQUEST message is set to 1;
• the TNL Available Capacity Indicator IE, if the first bit, "TNL Available Capacity Ind Periodic" of the Report Characteristics IE included in the RESOURCE STATUS REQUEST message is set to 1;

If the Reporting Periodicity IE is included in the RESOURCE STATUS REQUEST message, this indicates the periodicity for the reporting of periodic measurements. The gNB-CU-UP shall report only once, unless otherwise requested within the Reporting Periodicity IE.

If any of the requested measurements cannot be initiated, gNB-CU-UP shall send a RESOURCE STATUS FAILURE message with an appropriate cause value.

If the initiating gNB-CU-CP does not receive either RESOURCE STATUS RESPONSE message or RESOURCE STATUS FAILURE message, the gNB-CU-CP may reinitiate the Resource Status Reporting Initiation procedure towards the same gNB-CU-UP, provided that the content of the new RESOURCE STATUS REQUEST message is identical to the content of the previously unacknowledged RESOURCE STATUS REQUEST message with the same Transaction ID. If the Report Characteristics IE bitmap is set to "0" (all bits are set to "0") in the RESOURCE STATUS REQUEST message then gNB-CU-UP shall initiate a RESOURCE STATUS FAILURE message with an appropriate cause value. If the gNB-CU-UP receives a RESOURCE STATUS REQUEST message which includes the Registration Request IE set to "start" and the gNB-CU-CP Measurement ID IE corresponding to an existing on-going load measurement reporting, for which a different Transaction ID is used, then gNB-CU-UP shall initiate a RESOURCE STATUS FAILURE message with an appropriate cause value.

This procedure is initiated by gNB-CU-UP to report the result of measurements admitted by gNB-CU-UP following a successful Resource Status Reporting Initiation procedure. The procedure uses non UE-associated signalling.

The gNB-CU-UP shall report the results of the admitted measurements in RESOURCE STATUS UPDATE message. The admitted measurements are the measurements that were successfully initiated during the preceding Resource Status Reporting Initiation procedure.

Not applicable.

Void.