Wi-Fi to LTE Success Call Flow

This section describes the Wi-Fi to LTE success call flow.

Wi-Fi to LTE Success Call Flow
Wi-Fi to LTE Success Call Flow Description

Step

Description

1

The MME sends the Create Session Request to the GTP-EP(S11) with:

  • RAT as EUTRAN

  • The handoff indicator set to TRUE.

2

The GTP-EP(S11) forwards the Create Session Request to the SGW-SVC.

3

The SGW-SVC sends the Sx Establishment Request to the Protocol-Sxa.

4

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

5

The SGW-SVC sends the Create Session Request (with HI) to the GTP-EP(S5).

6

The GTP-EP(S5) forwards the Create Session Request (with HI) to the PGW.

7

The PGW sends the Create Session Response to the GTP-EP(S5).

The PGW provides IPv6 Prefix.

8

The GTP-EP(S5) forwards the Create Session Response to the SGW-SVC.

9

The SGW-SVC sends the Sx Modification Request to the Protocol-Sxa.

10

The Protocol-Sxa sends the Sx Modification Response to the SGW-SVC.

11

The SGW-SVC sends the Create Session Response to the GTP-EP(S11).

12

The GTP-EP(S11) sends the Create Session Response to the MME.

13

The MME sends the Modify Bearer Request (with HI) to the GTP-EP(S11).

14

The GTP-EP forwards the Modify Bearer Request (with HI) to the SGW-SVC.

15

The SGW-SVC sends the Sx Modification Request to the Protocol-Sxa.

16

The Protocol-Sxa sends the Sx Modification Response to the SGW-SVC.

17

The SGW-SVC forwards the Modify Bearer Request (with HI) to the GTP-EP(S5).

18

The GTP-EP(S5) forwards the Modify Bearer Request (with HI) to the PGW.

19

The PGW sends the Modify Bearer Response to the GTP-EP(S5).

20

The GTP-EP(S5) forwards the Modify Bearer Response to the SGW-SVC.

21

The SGW-SVC forwards the Modify Bearer Response to the GTP-EP(S11).

22

The GTP-EP(S11) forwards the Modify Bearer Response to the MME.

The S1 SGW FTEID is the same as the S1-U SGW FTEID sent in Create Session Response from the SGW-SVC to the MME.

The SGW-SVC can now send the downlink packets to the eNodeB, and the switching of the data path from Wi-Fi to LTE occurs after the Modify Bearer Response.