This feature allows you to limit the input or output transmission rate of a class of traffic based on user-defined criteria. It also enables the system to mark packets according to a user-defined criterion, such as the IP precedence value, the QoS group, or the DSCP value. Such traffic can then be dropped or transmitted, as desired.
A policer typically drops traffic that is out of profile. For example, the rate-limiting policer either drops the packet or rewrites its IP precedence, resetting the type of service bits in the packet header. Policers can have two or three colors.
A two-color policer lets you identify two types of traffic:
- Conforming traffic (CIR-Committed Information Rate)
- Exceeding traffic (above CIR)
The traffic ...