Create Session Request with Dedicated Bearer EBI Call Flow

This section describes the Create Session Request with the Dedicated EBI call flow.

CSReq with Dedicated Bearer EBI Call Flow
CSReq with Dedicated Bearer EBI Call Flow Description

Step

Description

1

The MME sends a Create Session Request with the TIED value as zero to the GTPC-EP(S11).

2

The GTPC-EP(S11) forwards the Create Session Request with TIED value as zero to the SGW-SVC.

3

The MME and the PGW process the Initial Attach PDN with the EBI-5 process.

4

The MME sends the Create Session Request with EBI-6 to the GTPC-EP.

5

The GTPC-EP forwards the Create Session Request with EBI-6 to the SGW-SVC.

6

The MME and PGW establish the PDN with the EBI-6 connection.

7

The MME and PGW complete the Create Dedicated Bearer with EBI-7 process.

8

If the SGW and MME are not in sync, then MME sends a Create Session Request with EBI-6 present in SGW.

9

The GTPC-EP sends a CSReq with EBI-7 to SGW.

10

After receiving the Create Session Request, the SGW-SVC:

  • Cleans up the PDN with default EBI=6.

  • Sends the Sx signalling to UPF to clear the session.

  • Performs the Create Session Request as new PDN-Setup.

The SGW sends a Sx Session Delete Request on PDN-2 to Protocol-SXA.

11

The Protocol-SXA forwards the Sx Session Delete Request to SGW-UPF.

12

The SGW sends a Session Establishment Request to the Protocol-SXA.

13

The Protocol-SXA forwards a Sx Session Establishment Request to SGW-UPF.

14

The SGW-UPF responds to the Protocol-SXA with the Sx Session Establishment Response.

15

The Protocol-SXA sends the Sx Session Establishment Response to the SGW-SVC.

16

The SGW-SVC sends the Create Session Request containing TIED=0x80002002, EBI-7 to the GTPC-EP.

17

The GTPC-EP sends the Create Session Request containing TIED=0x80002002, EBI-7 to the PGW.

18

The PGW sends a Create Session Response to the GTPC-EP.

19

The GTPC-EP responds to the SGW-SVC with the Create Session Response.

20

The SGW-SVC forwards the response to the GTPC-EP.

21

The GTPC-EP sends the Create Session Response to the MME.