Content for  TS 23.273  Word version:  18.5.0

This step is the same as step 1 of clause 6.1.2 and step 1 of clause 6.3.1, with the difference that the LCS request is targeting a group of UE identified by a group ID. The GMLC may map the external/internal group ID to the list of UE ID (i.e. SUPI) using Nudm_SDM_Get (Group Identifier Translation, External Group Identifier) service operation.

The NEF shall send a Ngmlc_Location_ProvideLocation Request to the GMLC with the group of UE identified by a group ID to indicate a bulk operation procedure. If deferred location is requested the NEF shall include an Event type to indicate that deferred location is requested and provides an LDR reference number (Notification Correlation ID) to be used for event reporting at steps 6b-1 and 11b-1. If immediate location is requested the NEF shall not provide an Event type to indicate that immediate location is requested and provides a Notification Correlation ID to be used for reporting at steps 6b-1.

he NF (e.g. NWDAF) shall send a Ngmlc_Location_ProvideLocation Request to the GMLC with the group of UE identified by a group ID to indicate a bulk operation procedure.

If deferred location is requested from the LCS Client, the GMLC responds with an acknowledgment.

The GMLC responds with a Ngmlc_Location_ProvideLocation Response. GMLC may decide whether completely or partially (i.e. accept part of the UE(s) within the group identified by the group ID in step 1) reject the location request. If GMLC decides to partially reject the location request, GMLC will respond to the LCS client /AF with a proper error cause.

The NEF acknowledges the execution of the Nnef_EventExposure_Subscribe.

If deferred location is requested from the NF, the GMLC responds with an acknowledgment.

The GMLC invokes a Nudm_SDM_Get (LCS privacy, SUPI) service operation towards the UDM to get the UE LCS privacy profile of the target UE. The GMLC checks the privacy settings. For the UE whose privacy setting does not allow it to be located, steps 4 and 5 are skipped. The GMLC may also subscribe to and receive notification of UE privacy profile updates according to steps 0 and 4 of clause 6.12.1.

The GMLC invokes a Nudm_UECM_Get service operation towards the UDM of the target UE with SUPI of this UE. The UDM returns the current serving AMF ID to the GMLC.

If no AMF ID is returned at step 4:

• if it is a deferred location request and the GMLC supports the storage of the LCS service request for a group of UE, the GMLC subscribes the UE reachability status to the UDM using Nudm_EventExposure_Subscribe service operation with the data key "SUPI";
• otherwise, this step is skipped and the GMLC returns an appropriate error cause to the LCS client or NEF at step 6.

If the UDM returns the current serving AMF ID to the GMLC at step 4:

• the GMLC initiates 5GC_MT_LR procedure (from step 4 onwards) as described in clause 6.1.2, with the difference that Step 24 is skipped (as it is replaced by step 6 below); The GMLC shall not include the Notification Correlation ID received from NEF in step 1b-2.
• or the GMLC initiates Deferred 5GC-MT-LR Procedure (from step 4 onwards) as described in clause 6.3.1 with the difference that steps 8,21 and 30 are skipped (as it is replaced by steps 2, 6 and 11 below) and that GMLC assign LDR reference numbers (separate number for each UE) to be used for event reporting at steps 20 and 29.

The GMLC receives response messages as defined in clause 6.1.2 step 22 or 23 or GMLC receives notification messages as defined in clause 6.3.1 step 28 or 29. The GMLC sends one or more LCS Service Responses to the LCS Client to convey UE locations or event reports.

The GMLC receives response messages as defined in clause 6.1.2 step 22 or 23 or GMLC receives notification messages as defined in clause 6.3.1 step 28 or 29. The GMLC maps the messages to the Request received in step 1b-2 and invokes one or more Ngmlc_Location_EventNotify service operations towards the NEF to convey UE locations or event reports. GMLC may aggregate one or more UE location estimates / event reports in each message sent to NEF.

The NEF invokes one or more Nnef_EventExposure_Notify service operations towards the AF, to convey UE locations or event reports , received from GMLC in step 6b-1.

The GMLC receives response messages as defined in clause 6.1.2 step 22 or 23 or GMLC receives notification messages as defined in clause 6.3.1 steps 28 or 29. The GMLC sends one or more Ngmlc_Location_EventNotify to the NF to convey UE locations or event reports.

For the deferred location request, if any UE in the group didn't get its serving AMF ID at step 4, the GMLC may store the LCS service request locally if the GMLC supports the storage of the LCS service request for a group of UE; otherwise, this step is skipped.

UE performs the registration as described in clause 4.2.2 of TS 23.502, during which an AMF is selected to serve the UE, and the AMF ID is stored into UDM.

UDM notifies the GMLC who had subscribed the UE registration at step 5a using Nudm_EventExposure_Notify service operation, which includes "SUPI" and UE registration status.

GMLC initiates Deferred 5GC-MT-LR Procedure as described in step 5b.

The GMLC receives notification messages as defined in clause 6.3.1 step 28 or 29. The GMLC sends one or more LCS Service Responses to the LCS Client to convey UE locations or event reports.

The GMLC receives notification messages as defined in clause 6.3.1 step 28 or 29. The GMLC maps the messages to the Request received in step 1b-2 and invokes one or more Ngmlc_Location_EventNotify service operations towards the NEF to convey UE locations or event reports. GMLC may aggregate one or more UE location estimates / event reports in each message sent to NEF.

The NEF invokes one or more Nnef_EventExposure_Notify service operations towards the AF, to convey event reports received from GMLC in step 11b-1.

The GMLC receives notification messages as defined in clause 6.3.1 steps 28 or 29. The GMLC sends one or more Ngmlc_Location_EventNotify to the NF to convey UE locations or event reports.