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

Step |
Description |
---|---|
1 |
The MME sends the Create Session Request to the GTP-EP(S11) with:
|
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. |