Step 1.
Step 2.
For non-roaming case and if 5GC GMLC and EPC GMLC are combined, steps 2a and 2b are skipped. Otherwise the 5GC GMLC may derive an address of a EPC GMLC or 5GC+EPC GMLC, either received together with the network address of the current serving node) from the UDM/HSS in step 1, by internal configuration or by query to NRF.
Step 2a.
If an address of a EPC GMLC is derived, the 5GC GMLC then sends the Lr location request to the EPC GMLC. If the result of privacy check indicates that the notification (and verification) based on current location is needed, the 5GC GMLC shall send a location request to the VGMLC indicating "positioning allowed without notification".
Step 2b.
If an address of an 5GC+EPC GMLC is derived, the 5GC GMLC invokes a Ngmlc_Location_ProvideLocation service operation towards the 5GC+EPC GMLC. If the result of privacy check indicates that the notification (and verification) based on current location is needed, the 5GC GMLC invokes the service request indicating "positioning allowed without notification"
Step 3.
Step 4.
For non-roaming case and if 5GC GMLC and EPC GMLC are combined, step 4a and 4b are skipped. Otherwise the following applies:
Step 4a.
If step 2a was performed, the EPC GMLC forwards the location estimation of the target UE, its age, its accuracy and optionally the information about the positioning method to the 5GC GMLC.
Step 4b.
If step 2b was performed, the 5GC+EPC GMLC forwards the location estimation of the target UE, its age, its accuracy and optionally the information about the positioning method to the 5GC+EPC GMLC in a Ngmlc_Location_ProvideLocation service Response.
Step 5.
If the privacy check in step 1 indicates that further privacy checks are needed, the 5GC GMLC shall perform an additional privacy check in order to decide whether the 5GC GMLC can forward the location information to the LCS client or AF or send a notification if the result of the privacy check requires the notification and verification based on current location. One example when this additional privacy check is needed is when the target UE user has defined different privacy settings for different geographical locations. When an additional privacy check is not needed, the (H)GMLC skips steps 6-8.
Step 6.
For non-roaming case and if5GC GMLC and EPC GMLC are combined, step 6a and 6b are skipped. Otherwise the following applies:
Step 6a.
If step 2a was performed and if the result of privacy checks in step 5 indicates that the notification (and verification) based on current location is needed, and in the case of roaming, the 5GC GMLC shall send a location request to the EPC GMLC indicating "notification only".
Step 6b.
If step 2b was performed and if the result of privacy checks in step 5 indicates that the notification (and verification) based on current location is needed, and in the case of roaming, the 5GC GMLC shall invokes a Ngmlc_Location_ProvideLocation service operation to the 5GC+EPC GMLC indicating "notification only".
Step 7.
Step 8.
For non-roaming case and if 5GC GMLC and EPC GMLC are combined, step 8a and 8b are skipped. Otherwise the following applies:
Step 8a.
If step 2a was performed, the EPC GMLC forwards an indication of the result of notification and verification procedure to the 5GC GMLC.
Step 8b.
If step 2b was performed, the 5GC+EPC GMLC forwards an indication of the result of notification and verification procedure to the 5GC GMLC.
Step 9.