Content for &nbsp; TS 23.558 &nbsp; Word version:&nbsp; 19.3.0

The EAS sends UE location request to the EES. The UE location request shall include the UE Identifier. It may also include location granularity to indicate requested format of the location e.g. GPS Coordinates, Cell ID, Tracking Area ID, or civic addresses (e.g. streets, districts, etc.), which can be understood by the EAS and location QoS.

The EES checks the UE location:

If the UE location request from the EAS includes the location granularity, the EES considers the location granularity parameter for checking the location of the UE.
If the EES has a valid locally cached location of the UE, the EES may use this cached UE location to respond to the EAS. Otherwise, the EES utilizes the capabilities of the 3GPP core network as specified in clause 8.10.3.
The EES may modify the format of the UE location to fit to the location granularity requested from the EAS in the step 1, if supported. For example, if the EES receives the UE location in a format of tracking area ID or cell ID, the EES can modify the representation of the location information to the GPS Coordinates, or civic addresses (e.g. streets, districts, etc.) as requested by the EAS.

Figure 8.6.2.2.3.2-1: UE location API: Subscribe operation

If successful, the EES responds to the EAS with the location of the UE, and optionally the timestamp of the location.

8.6.2.2.3 Subscribe-notify model p. 115

8.6.2.2.3.1 General p. 115

Void

8.6.2.2.3.2 Subscribe p. 115

Figure 8.6.2.2.3.2-1 illustrates the subscribe operation between the EAS and the EES for continuous UE location reporting.

Pre-conditions:

The EAS is authorized to discover and to use UE location API provided by the EES;
The EES is authorized to use 3GPP network exposure capability (e.g. Nnef Event Exposure API) for UE location, based on service level agreement with MNO; and
UE Identifier or UE Group ID between EAS and the EES is authorized for the UE location API.

The EAS sends UE location subscribe request to the EES for tracking a UE's location continuously. The UE location subscribe request shall include the UE Identifier or UE Group ID and may include proposed expiration time. It may also include location granularity to indicate requested format of the location e.g. GPS Coordinates, Cell ID, Tracking Area ID, or civic addresses (e.g. streets, districts, etc.), which can be understood by the EAS and location QoS.

The EES checks if the request from the EAS is authorized. If authorized, the EES sends success response to the EAS and utilizes the UE location exposure capability of the 3GPP core network as specified in clause 8.10.3. The EES requests continuous location reporting from the 3GPP system to have up to date location information of the UE(s).

Figure 8.6.2.2.3.3-1: UE location API: Notify operation

The EES may subscribe to UE expected behaviour analytics (UE mobility) as described in TS 23.288.

Step 4.

The response includes the subscription identifier and may include the expiration time, indicating when the subscription will automatically expire. To maintain the subscription, the EAS shall send a UE location subscription update request prior to the expiration time. If a UE location subscription update request is not received prior to the expiration time, the EES shall treat the EAS as implicitly unsubscribed. If it is not authorized, the EES sends failure response with rejection cause.

8.6.2.2.3.3 Notify p. 116

Figure 8.6.2.2.3.3-1 illustrates the notify operation between the EES and the EAS for continuous location.

Pre-conditions:

The EAS has subscribed to UE location API provided by the EES.

Reproduction of 3GPP TS 23.558, Fig. 8.6.2.2.3.3-1: UE location API: Notify operation

The EES detects the location of a UE e.g., receiving location of a UE from the 3GPP system. The EES may cache the detected location information locally with timestamp as the latest location information of the UE(s) and start the notification aggregation for a group of UEs. The EES decides whether to aggregate and the aggregation period based on the analytics result received from the 3GPP Core Network, local policy and UE location subscription information received from the EAS. The EES determines to notify the location information of the UE(s) to the EAS which has subscribed for UE(s)'s location.

Figure 8.6.2.2.3.4-1: UE location API: Subscription update operation

The EES sends UE location notification to the EAS. The EES includes the location of the UE(s). Each UE location includes UE ID and location type and may include the location accuracy and the timestamp of the location.

The EES may modify the format of location information to fit to the location granularity requested from the EAS during the subscribe operation, if supported. For example, if the EES receives the UE location in a format of tracking area ID or cell ID, the EES can modify the representation of the location information to the GPS Coordinates, or civic addresses (e.g. streets, districts, etc.) as requested from the EAS.

8.6.2.2.3.4 Subscription update p. 117

Figure 8.6.2.2.3.4-1 illustrates the subscription update operation between the EAS and the EES.

Pre-conditions:

The EAS has subscribed to UE location API provided by the EES.

Reproduction of 3GPP TS 23.558, Fig. 8.6.2.2.3.4-1: UE location API: Subscription update operation

The EAS sends UE location subscription update request to the EES. The request includes the subscription identifier of the subscription to be updated. The UE location subscription update request may also include proposed expiration time for the updated subscription, updated Location granularity and Location QoS.

The EES checks if the request from the EAS is authorized. If authorized, the EES updates the subscription request and may update the UE location subscription in the 3GPP Core Network.

Figure 8.6.2.2.3.5-1: UE location API: unsubscribe operation

The EES may update the subscription to the UE expected behaviour analytics.

Step 4.

The EES sends the UE location subscription update response to the EAS.

8.6.2.2.3.5 Unsubscribe p. 118

Figure 8.6.2.2.3.5-1 illustrates the unsubscribe operation between the EAS and the EES to stop the UE location notifications.

Pre-conditions:

The EAS has subscribed to UE location API provided by the EES.

Reproduction of 3GPP TS 23.558, Fig. 8.6.2.2.3.5-1: UE location API: unsubscribe operation

The EAS sends the UE location unsubscribe request to the EES.

The EES checks if the EAS is authorized or not. If authorized, the EES terminates the subscription of the EAS and unsubscribes the UE location from the 3GPP Core Network.