No User Connect Retry Timer Call Flow
This section describes the No User Connect Retry Timer call flow.

Step |
Description |
---|---|
1 |
Received DDN ACK success at the S11-GTP-EP pod. |
2 |
The transaction started while sending the DDN ends here. S11-GTP-EP sends the DDN ACK success to the SGW-service pod. |
3 |
No User Connect Retry timer is started at the SGW-C pod. This timer is configurable. SGW-service pod updates the CDL. |
4 |
SGW-service pod sends the DDN Request to the S11-GTP-EP pod, when:
A new transaction S-T1 is created. |
5 |
A new E-T2 transaction is created. S11-GTP-EP pod forwards the DDN Request to MME. |
6 |
MME sends the DDN Response to the S11-GTP-EP. |
7 |
The transaction E-T2 started at step four is complete. S11-GTP-EP forwards the DDN Response Success to the SGW-service pod. |
8 |
S-T1 transaction started at step two is completed. No User Connect Retry timer is started at the SGW-C pod. This timer is configurable. SGW-service pod updates the CDL. |
9 |
If DDN Failure Indication/MBR is not received, No User Connect Retry expiry triggered. A new transaction S-T3 is created. SGW-service pod sends the background IPC request for Sx Modification request to the PFCP-EP pod (DROBU flag and Apply Action as BUFFER). |
10 |
A new transaction P-T4 is created. PFCP-EP pod sends the Sx Modification Request to the SGW-U pod. |
11 |
PFCP-PE pod receives the Sx Modification Response. |
12 |
The transaction P-T4 started at step nine is complete. PFCP-EP pod sends the background IPC response to the SGW-service pod. |
13 |
The transaction S-T3 started at step eight is complete. CDL is updated. |