Content for  TS 23.434  Word version:  19.3.0

The VAL server sends Monitor Location Subscription Request to LM server including target VAL UE Identifier(s), predetermined or dynamic area of interest information, notification interval and notification URI where the VAL server intends to receive the notifications from LM server regarding target VAL UE's presence in a given area, interested notification information, dynamic geofencing conditions.

• "Area of interest" is the location information, which the VAL server wishes to monitor the target VAL UE's location adherence. This parameter can include an area of interest information and other relevant parameters. In the case of dynamic area of interest, it includes a reference VAL UE Identifier and its proximity range.
• "Notify_Interval" represents the periodic interval in which the LM server needs to notify target VAL UE's location information to the VAL server. When the target VAL UE moves away from the "Area of interest", then the LM server ignores the "Notify_Interval" and sends the location notification to the VAL server immediately.
• "dynamic geofencing conditions" includes a temporal condition(s) (e.g. time of day and day of week), connectivity condition(s) (e.g. operator information, roaming status, access type) and/or a spatial condition(s) (e.g. location area(s)) for the reference VAL UE. For instance, the monitoring is valid when a reference UE is served by operator A without using satellite in location area X from 7:00am to 9:00am on working days.

If dynamic area of interest information and dynamic geofencing conditions are received, the LM server requests 3GPP CN (e.g. NEF service for location, access type and roaming status monitoring as specified in TS 23.502) to monitor the reference UE location change, access type change and roaming status change, in order to determine spatial dynamicity in area of interest related to the target UE(s). If spatial condition is received, the LM server also requests 3GPP CN (i.e. NEF service for area of interest monitoring as specified in TS 23.502) to know whether the reference UE is in the VAL server's predetermined area (e.g. PLMN x). The LM server will process the monitoring considering the received dynamic geofencing conditions for the reference UE.

If dynamic area of interest information is received, the LM server requests 3GPP CN (i.e. NEF service for loss of connectivity as specified in TS 23.502) for both target UE(s) and reference UE.

LM server processes the Area of interest information in the request, and then subscribes to target UE location monitoring as specified in TS 23.502 with appropriate parameters mapping. Based on the subscription, the LM server receives the target VAL UE location information periodically from the 3GPP core network. The LM server also invokes NEF service for Area of Interest monitoring as specified in clause 5.3.3 of TS 23.256 to know whether the target VAL UE is in the VAL server's predetermined or dynamic area of interest.

LM server shall use the Location information procedures as specified in clause 9.3.7 and clause 9.3.10, to periodically obtain the target VAL UE location information. Based on the geographic information from the VAL server, the LM server may determine to additionally include the positioning methods in SEAL LMS procedures to obtain location information.

LMS may periodically obtain the target VAL UE location information from the 3rd party location management server based on the geographic information from the VAL server.

LM server, after successful subscription according to steps 2~4, sends Monitor Location Subscription response, indicating that the LM server accepts VAL server's request and will monitor the location of the target VAL UE(s) to verify if the target VAL UE(s) is in the area of interest.

LM server processes the location information received from SEAL Location Information procedures, the 3GPP core network and/or the 3rd party location management server, and validates the information. If the location information is matching, then the LM server shall check if the VAL UE's current location is within the predetermined or dynamic area of interest received in step 1.

LM server verifies its determined target VAL UE location status (i.e. presence or absence with regard to the predetermined area of interest) with the retrieved 3GPP core network result from the NEF monitoring service for Area of Interest. The LM server will continue with step 7, step 8 and step 9 as applicable.

If the location information received from Location management client, the 3GPP core network and/or the 3rd party location management server do not match or the NEF reported Area of Interest monitoring result does not match with the determined target VAL UE location status (present/absence) in LM server, then the LM server shall consider the target VAL UE as outside from its specified area of interest and shall notify ("Notify Mismatch Location" message) the VAL server of the same, including target VAL UE ID and the location information from LM server, the 3GPP core network and/or the 3rd party location management server in the notification message.

If the target VAL UE's current location is from Location management client, the 3GPP core network and/or the 3rd party location management server matches, and either not in the predetermined area of interest received from VAL server in Monitor Location Subscription Request message or not within the proximity range of the reference UE, and such out of area of interest result is also aligned with the NEF reported area of interest monitoring result, then the LM server considers the target VAL UE as outside from its specified area of interest and shall notify the VAL server that the target VAL UE's current location is outside of area of interest and target VAL UE ID in "Notify Absence" message.

When the target VAL UE's current location is either in the predetermined area of interest or in the proximity range of the reference UE, and such in area of interest result is also aligned with the NEF reported area of interest monitoring result, then the LM server shall notify ("Notify Presence" message) the VAL server periodically, according to the "Notify_Interval" value in "Monitor Location Subscription Request" message, indicating the VAL server that the target VAL UE is within the area of interest, along with target VAL UE's current location information.

If the LM server is notified by the 3GPP CN about loss of connectivity for the reference UE or target UE(s), then the LM server notifies ("Notify Unknown" message with detailed reason) the VAL server indicating that the LM server does not know whether the target UE is "Presence" or "Absence", therefore the dynamic geofencing monitoring for the impacted target UE(s) is suspended.

The VAL server sends a location area monitoring subscription request to the location management server to subscribe to the list of UEs moving in or moving out of the specific location area. In the request message, the VAL server includes the information as specified in Table 9.3.2.14-1. The location information criteria may include the geographic location information or the VAL service area identified by the VAL service area ID where the UEs moving in or moving out to be monitored, or it may include reference UE information where in the UEs moving in or moving out of given application defined proximity range from the reference UE (target UE) to be monitored. The reference UE information may include VAL UE ID. If the VAL server initiates the subscription for the Geofencing service, the Geofencing monitoring events (i.e. the UEs moving in/out of the pre-defined location area, the number of UEs moving in/out of the pre-defined location area, the time period of UEs enter/leave the pre-defined location area) can be included in the request message as specified in Table 9.3.2.14-1.

The location management server shall check if the VAL server is authorized to initiate the location area monitoring subscription request.

The location management server replies with a location area monitoring subscription response indicating the subscription status. In the response message, the location management server includes the information as specified in Table 9.3.2.15-1.

The VAL server sends a location area monitoring subscription modify request to the location management server to modify the subscription to the list of UEs moving in or moving out of the specific location area. In the request message, the VAL server includes the information as specified in Table 9.3.2.17-1.

The location management server shall check if the VAL server is authorized to initiate the location area monitoring subscription modification request.

The location management server replies with a location area monitoring subscription modify response indicating the subscription status. In the response message, the location management server includes the information as specified in Table 9.3.2.18-1.

The VAL server sends a location area monitoring unsubscrbe request to the location management server to unsubscribe to the subscription to the list of UEs moving in or moving out of the specific location area. In the request message, the VAL server includes the information as specified in Table 9.3.2.19-1.

The location management server replies with a location area monitoring unsubscrbe response indicating the subscription status. In the response message, the location management server includes the information as specified in Table 9.3.2.20-1.

One of the events occurs at the location management server as specified in the subscribe request. The location management server identifies the UEs which are moved into the area or moved out of the area based on their location data and time stamp of the location. The LMS may report the list of all UEs in the given location or UEs moved in and moved out. When the Geofencing service is triggered, the LM Server also checks whether the UE is inside/outside the area based on the location information criteria as defined in Table 9.3.2.14-1 and the received UE location data. Further, the LM Server statistics and reports the Geofencing monitoring events (e.g. the list of UEs moving in/out of the location area, the number of UEs moving in/out of the location area, the time period of UEs enter/leave the location area, etc.) to the VAL server.

The location management server sends a location area monitoring notification to the VAL server. In the notification message, the location management server includes the information as specified in Table 9.3.2.16-1. If the LM server didn't obtain any UE location information due to UE issues or network issues in step 1, it informs the VAL server with the proper reason (e.g., "UE cannot be connected") in the notification report.

After received the Geofencing information report from the LM Server, the VAL server may take some actions to inform the VAL UE (e.g. send the alarms or warnings to the UE).