RADIUS-initiated Detach Procedure
The following figure shows the call flow for E-UTRAN RADIUS disconnect messages.

Step | Description |
---|---|
1 |
AAA Radius Disconnect Message to SMF. |
2 |
SMF sends back Radius Disconnect acknowledgment. |
3 |
SMF sends PCRF Session Modification Request (Update FAR with DROP) to UPF. |
4 |
UPF responds to SMF with PCRF Session Modification Response. |
5 |
SMF sends Delete Bearer Request to S-GW |
6 |
S-GW forwards Delete Bearer Request to MME. |
7 |
MME responds to S-GW with Delete Bearer Response. |
8 |
S-GW forwards Delete Bearer Response to SMF. |
9 |
SMF sends PCRF Session Deletion Request to UPF. |
10 |
UPF responds to SMF with PCRF Session Deletion Response. |
11 |
SMF sends CCR-T to OCS. |
12 |
SMF sends Accounting Request(Stop) to AAA. |
13 |
OCS responds to SMF with CCA-T. |
14 |
SMF responds to AAA with Accounting Response(Stop). |
14 |
SMF sends CCR-T to PCRF. |
15 |
PCRF responds to SMF with CCA-T. |