PCF-initiated Bearer Modification for EPS session on SMF Call Flow
This section describes the PCF-Initiated Bearer Modification for EPS session on SMF call flow.

Step | Description |
---|---|
1 | PCF initiates the N7 Policy Update Notify with the updated parameters of QoS or TFT toward SMF. |
2 | SMF sends the “200 OK” acknowledgment to PCF. The PCC rules that the PCF provides are mapped to TFTs for the modified dedicated bearer. The associated QoS is mapped to 4G QoS. |
3 | SMF sends the Update Bearer Request to SGW. |
4 | SGW sends the Update Bearer Response to SMF with EPS Bearer ID and the modified QoS or TFT for the associated bearer. |
5 | SMF initiates the PFCP Modification request toward UPF. |
6 | UPF sends the PFCP Modification Response to SMF with updated QER. |
7 | SMF sends the PCF Notify message to PCF. |
8 | PCF sends the “200 OK” acknowledgment to SMF. |