Help us improve your experience.

Let us know what you think.

Do you have time for a two-minute survey?


Defining Aliases for CoS Value Bit Patterns

To define a CoS value alias, include the code-point-aliases statement at the [edit class-of-service] hierarchy level:

The CoS marker types are as follows:

  • dscp—Differentiated Services code point aliases for IPv4 packets.

  • dscp-ipv6—Differentiated Services code point aliases for IPv6 packets.

  • exp—Layer 2 CoS values for MPLS packets.

  • ieee-802.1—Layer 2 IEEE 802.1 CoS values.

  • ieee-802.1—Layer 2 IEEE 802.1ad (DEI) CoS values.

  • inet-precedence—IP precedence for IPv4 packets. IP precedence mapping requires only the first three bits of the DSCP field.

For example, you might configure the following aliases:

To specify this configuration:

  1. Specify the code-point-alias type as DSCP:
  2. Specify the alias names and DSCP 6-bit pattern.

This configuration produces the following mapping:

The following notes explain certain results in the mapping:

  • my1 110001:

    • 110001 was not mapped to anything before, and my1 is a new alias.

    • Nothing in the default mapping table is changed by this statement.

  • my2 101110:

    • 101110 is now mapped to my2 as well as ef.

  • be 000001:

    • be is now mapped to 000001.

    • The old value of be, 000000, is not associated with any alias. Packets with this DSCP value are now mapped to the default forwarding class.

  • cs7 110000:

    • cs7 is now mapped to 110000, as well as nc1 and cs6.

    • The old value of cs7, 111000, is still mapped to nc2.