Change Notification with ULI Change

This section describes the change notification request and the response call flow with ULI change.

Change Notification with ULI Call Flow Description

Step

Description

1

The MME sends a Change Notification Request (for ULI change) to SGW.

2

The SGW forwards a Change Notification Request to SMF.

3

The SMF sends a N4 Session Modification Request for query URR to UPF based on the event triggers armed.

Note

USER_LOCATION_CHANGE event triggers for ULI change.

4

The UPF responds with a N4 Session Modification Response with Gy, and radius URR SMF based on Gy and radius configuration(enabled/disabled).

5

The SMF sends a Change Notification Response to SGW.

6

The SGW forwards a Change Notification Response to MME.

7

Based on the URRs received in N4 Modification Response, Gy, and radius signaling occurs.

8

The SMF sends a CCR-U to OCS and Radius Accounting Request to AAA.

9

The responds with a CCA-U and AAA with Radius Accounting Response.

10

The SMF sends a N4 Session Modification Request for update URR to UPF.

11

The UPF sends a N4 Session Modification Response to SMF.

12

If the event trigger arms, the SMF sends a CCR-U to the PCRF.

Note

USER_LOCATION_CHANGE event triggers for ULI change.

13

The PCRF then sends a CCA-U to SMF.

14

Now, Bearer creation/update/deletion occurs based on Gx CCA-U contents.