UE-Triggered Service Request with PGW Interaction Call Flow

This section describes the UE-Triggered Service Request with PGW Interaction call flow.

UE-Triggered Service Request with PGW Interaction Call Flow
UE-Triggered Service Request with PGW Interaction Call Flow description

Step

Description

1

The MME sends the Modify Bearer Request with s1-eNodeB F-TEID to cnSGW-C when the UE changes from the IDLE to ACTIVE state.

2

The S11-GTP-EP decodes the UDP message and converts it into the gRPC message. This gRPC message is sent to the SGW-Service pod, which handles the UE session using TEID.

3

The SGW-Service pod finds the subscriber context using the local ingress TEID.

It validates the Modify Bearer Request content and sends the Sx Modify Request to PFCP-EP.

4

The PFCP-EP sends the Sx Modify Request to the UPF through the UDP proxy.

5

The UPF1 processes the Sx Modify Request and sends the Sx Modify Response message.

6

The PFCP-EP sends the Sx Modify Response message to the SGW-Service pod.

7

The SGW-Service pod detects ULI or UE time zone change and sends the Modify Bearer Request message to S5-GTP-EP.

8

The S5-GTP-EP sends the Modify Bearer Request message to the PGW.

9

The PGW processes the Modify Bearer Request message and sends the Modify Bearer Response message.

10

The S5-GTP-EP sends the Modify Bearer Response message to the SGW-Service pod.

11

The SGW-Service pod moves PDN into the CONNECTED state and sends the update to CDL.

The CDL module updates the information in the database.

12

The SGW-Service pod sends the Modify Bearer Response message to the S11-GTP-EP.

13

The S11-GTP-EP sends the Modify Bearer Response message to the MME.

The MME processes the Modify Bearer Response message.