9.1.18 EPC Post Positioning Notification and Verification Procedure

23.2713GPPFunctional stage 2 description of Location Services (LCS)Release 17TS

Figure 9.21 illustrates the post positioning notification and verification procedure.

Figure 9.21: EPC Post Positioning Notification and Verification Procedure

1) Common PS and CS MT-LR procedure as described in clause 9.1.1.

2) The GMLC sends a Provide Subscriber Location message to the MME with an indication of "notification only". This message carries the UE subscriber’s IMSI. For a session related location request, the message also carries the APN-NI to which the user has established the session. For a value added LCS client, the message shall carry the client name, the external identity of the LCS client and the Requestor Identity (if that is both supported and available), optionally the message may also carry the Service Type. Also the message may carry the type of the LCS client name and also the type of the Requestor identity if the requestor identity was included. If the result of the privacy check at H-GMLC/PPR indicated that the codeword shall be sent to the UE user, the message may carry also the codeword received from the LCS client. For a PLMN operator LCS client, the message shall carry the internal identity of the LCS client. If the Requestor Identity is provided, the GMLC shall send it as separate information.

3) The MME first checks if the UE is detached or suspended. If this is the case, an error response is returned. The MME determines a required privacy related action as described in Annex A.3 based on the indicators of privacy related action in the PSL message from the GMLC.

If the UE is not using Control Plane CIoT EPS Optimisation and if the UE is in ECM-IDLE state, the MME performs a network triggered service request as defined in TS 23.401 [41] in order to establish a signalling connection with the UE and assign a specific eNodeB.

If the UE is using Control Plane CIoT EPS Optimisation, procedures for Mobile Terminated Data Transport in Control Plane CIoT EPS optimisation as defined in TS 23.401 [41] are performed by the MME to establish a signalling connection with the UE.

4) A notification invoke message is sent to the target UE indicating a location type of notification and verification only, the identity of the LCS client and the Requestor Identity (if that is both supported and available), whether privacy verification is required. Also the message may indicate the type of the LCS client name and also the type of the Requestor identity if the requestor identity was included. Moreover, the message may carry also the service type and the codeword.

5) The target UE notifies the UE user of the location request and, if privacy verification was requested, waits for the user to grant or withhold permission. The UE then returns a notification result to the MME indicating, if privacy verification was requested, whether permission is granted or denied. If the UE user does not respond after a predetermined time period, the MME shall infer a "no response" condition. The MME shall return an error response to the GMLC if privacy verification was requested and either the UE user denies permission or there is no response with the UE subscription profile indicating barring of the location request.

6) The MME returns the indication of successful notification and verification result, if it has received a NAS Location Notification Return Result indicating that permission is granted. If a LCS Location Notification Return Result message indicating that permission is not granted is received, or there is no response, with the requested privacy action or the UE subscription profile indicating barring of location, the MME shall return an error response to the GMLC.

7) Common MT-LR procedure in PS and CS domain as described in clause 9.1.1.