Code-Point Aliases Overview

A code-point alias assigns a name to a pattern of code-point bits. You can use this name instead of the bit pattern when you configure other class-of-service (CoS) components, such as classifiers, drop-profile maps, and rewrite rules.

When you configure classes and define classifiers, you can refer to the markers by alias names. You can configure user-defined classifiers in terms of alias names. If the value of an alias changes, it alters the behavior of any classifier that references it.

The following types of code points are supported by Junos operating system (OS):

• DSCP—Defines aliases for DiffServ code point (DSCP) IPv4 values.

  You can refer to these aliases when you configure classes and define classifiers.

• DSCP-IPv6—Defines aliases for DSCP IPv6 values.

  You can refer to these aliases when you configure classes and define classifiers.

• EXP—Defines aliases for MPLS EXP bits.

  You can map MPLS EXP bits to the device forwarding classes.

• inet-precedence—Defines aliases for IPv4 precedence values.

  Precedence values are modified in the IPv4 type-of-service (ToS) field and mapped to values that correspond to levels of service.