DSCP Marking

Differentiated Services Code Point (DSCP) marking allows network devices to prioritize different types of traffic based on their DSCP value. AMF supports updating the IP headers with configured DSCP information on outgoing packets on N2/SCTP interface, N26/GTPC interface, and SBI interface.

Feature History

Table 1. Feature History

Feature Name

Release Information

Description

DSCP Marking

 2025.03.0

AMF applies DSCP marking to outgoing packets on the N2/SCTP and N26/GTPC interfaces, ensuring that traffic is handled appropriately.

Command introduced:

  • config { instance instance-id instance_id { endpoint sctp { dscp dscp_value } } } — Used to configure the DSCP value for N2-SCTP interface.

  • config { instance instance-id instance_id { endpoint gtp { dscp dscp_value } } } — Used to configure the DSCP value for N26-GTPC interface.

Default Setting: Disabled – Configuration Required

DSCP marking for SBI interface

2026.02.0

AMF applies DSCP marking to outgoing packets on the SBI interfaces, ensuring that traffic is handled appropriately.

Command introduced:

config { instance instance-id instance_id { endpoint sbi { dscp dscp_value } } } — Used to configure the DSCP value for SBI interface.

Default Setting: Disabled – Configuration Required

Usage Guidelines for DSCP Marking

To configure DSCP marking:

  • Use CLI commands to set DSCP values for N2/SCTP, N26/GTPC, and SBI interfaces.

  • DSCP values can be configured as hexadecimal (e.g., 0x0-0x3F) or decimal (range: 0-63).

  • If DSCP value is not specified in the configuration then the default DSCP value is set to 0.

  • Configured values apply to all outgoing requests and responses on the specified interface.

  • DSCP marking is configured per interface, not per peer or session.

  • Supports runtime changes to DSCP values.

Configure DSCP for N2/SCTP Interface

Procedure

Step 1

Enter the instance configuration mode.

instance instance-id instance_id

Step 2

Configure the endpoint for the instance.

endpoint endpoint_name

Specify sctp as the endpoint type for the instance.

Step 3

Configure the DSCP value for the SCTP endpoint.

dscp dscp_value

DSCP value is either in hexadecimal string (range 0x0-0x3F) eg:0x3F or decimal value (range 0-63) eg:12.

Following is an example of the sample CLI output for the DSCP marking.

[amf] amf# show running-config instance instance-id 1 endpoint sctp
instance instance-id 1
 endpoint sctp
  replicas     2
  nodes        1
  internal-vip 29.29.29.29
  dscp         10
  service sctp-1
   interface sctp
    internal-port metrics 9705 admin 9703 ipc 9701 pprof 9707 keepalived 29001
    internal-vip 29.29.29.29
    vip-ip 29.29.29.29 vip-port 1000
   exit
  exit
  service sctp-2
   interface sctp
    internal-port metrics 9715 admin 9713 ipc 9711 pprof 9717 keepalived 29011
    internal-vip 29.29.29.29
    vip-ip 29.29.29.29 vip-port 1001
   exit
  exit
 exit
exit

Step 4

Save and commit the configuration.

Configure DSCP for N26/GTPC Interface

Procedure

Step 1

Enter the instance configuration mode.

instance instance-id instance_id

Step 2

Configure the endpoint for the instance.

endpoint endpoint_name

Specify gtp as the endpoint type for the instance.

Step 3

Configure the DSCP value for the GTPC endpoint.

dscp dscp_value

DSCP value is either in hexadecimal string (range 0x0-0x3F) eg:0x3F or decimal value (range 0-63) eg:12.

Following is an example of the sample CLI output for the DSCP marking.

[amf] amf# show running-config instance instance-id 1 endpoint gtp
instance instance-id 1
 endpoint gtp
  nodes        2
  retransmission timeout 4 max-retry 5
  internal-vip 27.27.27.27
  dscp         46
  vip-ip 27.27.27.27
  interface n26
   vip-ip 27.27.27.27
  exit
 exit
exit

Step 4

Save and commit the configuration.

Configure DSCP for SBI Interface

Procedure

Step 1

Enter the instance configuration mode.

instance instance-id instance_id

Step 2

Configure the endpoint for the instance.

endpoint endpoint_name

Specify sbi as the endpoint type for the instance.

Step 3

Configure the DSCP value for the SBI endpoint.

dscp dscp_value

DSCP value is either in hexadecimal string (range 0x0-0x3F) eg:0x3F or decimal value (range 0-63) eg:12.

Following is an example of the sample CLI output for the DSCP marking.

[amf] amf# show running-config instance instance-id 1 endpoint sbi
instance instance-id 1
 endpoint sbi
  replicas     1
  nodes        2
  loopbackPort 8091
  instancetype IPv6
  dscp 33 
  fqdn cisco-amf.3gppnetwork.org
  vip-ipv6 2001:172:16:186::4 vip-ipv6-port 8070