Custom IEs at UPF

This section lists the custom IEs that are available at UPF.

Extended Apply Action

The Extended Apply Action IE indicates the action(s) the UPF is required to apply to packets. It is coded as shown in the following figure.

Extended Apply Action IE

The octet 5 is encoded as follows:

  • Bit 1 – UL DROP (Drop Uplink): when set to 1, this indicates a request to drop uplink packets.

  • Bit 2 – DL DROP (Drop Downlink): when set to 1, this indicates a request to drop downlink packets.

  • Bit 3 – TERMFLOW (Terminate/Kill Flow) : when set to 1, this indicates a request to terminate the flow.

  • Bit 4 to 8 – Spare, for future use and set to 0.

QGR-INFO List

The QGR-INFO List IE indicates the information about the QoS Group received from the PCF to UPF which identifies the flow and applies the received parameters. It is coded as shown in the following figure.

QGR-INFO List IE

The octet 7 (bit vector for the QGR Information) is encoded as follows:

  • Bit 1 – PRECED (Precedence): when set to 1, this indicates precedence is present.

  • Bit 2 – QGRN (QGR Name): when set to 1, this indicates QGR Name is present.

  • Bit 3 – FAR : when set to 1, this indicates FAR ID is present.

  • Bit 4 – QER: when set to 1, this indicates QER ID is present.

  • Bit 5 to 8 – Spare, for future use and set to 0.

SMF encodes the QGR information based on this bit vector field.

Burst Size

The Burst Size IE indicates the information about the UL and DL burst size for MBR to UPF. It is coded as shown in the following figure.

Burst Size IE

Conform Action

The Conform Action IE indicates the action(s) the UPF is required to apply to packets for both UL and DL. It is coded as shown in the following figure.

Conform Action IE

Exceed Action

The Exceed Action IE indicates the action(s) the UPF is required to apply to packets for both UL and DL. It is coded as shown in the following figure.

Exceed Action IE

The following tables provide information on the custom IEs included in the N4 messages.

FAR Format

FAR ID

Unique ID

Extended Apply Action

Private IE to include Flow-Action Allow as well Discard Uplink, Discard Downlink, and Terminate Flow.

The value of Extended Apply Action is derived from FlowStatus IE value received in QosGroupOfRuledef IE from PCF.

QER Format

QER ID

Unique ID

Maximum Bitrate

MBR of QGR in Kbps.

  • UL MBR

  • DL MBR

Burst Size

Private IE to include the burst size.

  • UL Burst

  • DL Burst

Conform Action

Private IE to configure the conform action.

  • Uplink Action

  • Uplink ToS

  • Downlink Action

  • Downlink ToS

Exceed Action

Private IE to configure the exceed action.

  • Uplink Action

  • Uplink ToS

  • Downlink Action

  • Downlink ToS