Traffic Policing - HP 5830 Series Configuration Manual

CIR—Rate at which tokens are put into bucket C. It sets the average packet transmission or
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forwarding rate allowed by bucket C.
CBS—Size of bucket C, which specifies the transient burst of traffic that bucket C can forward.
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Excess burst size (EBS)—Size of bucket E, which specifies the transient burst of traffic that bucket E
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can forward.
Peak information rate (PIR)—Rate at which tokens are put into bucket E, which specifies the average
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packet transmission or forwarding rate allowed by bucket E.
CBS is implemented with bucket C and EBS with bucket E. In each evaluation, packets are measured
against the following bucket scenarios:
If bucket C has enough tokens, packets are colored green.
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• If bucket C does not have enough tokens but bucket E has enough tokens, packets are colored
yellow.
If neither bucket C nor bucket E has sufficient tokens, packets are colored red.
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Traffic policing

Traffic policing supports policing the inbound traffic and the outbound traffic.
A typical application of traffic policing is to supervise the specification of certain traffic entering a
network and limit it within a reasonable range, or to "discipline" the extra traffic to prevent aggressive
use of network resources by a certain application. For example, you can limit bandwidth for HTTP
packets to less than 50% of the total. If the traffic of a certain session exceeds the limit, traffic policing can
drop the packets or reset the IP precedence of the packets.
outbound traffic on an interface.
Figure 8 Traffic policing
Traffic policing is widely used in policing traffic entering the networks of ISPs. It can classify the policed
traffic depending on the evaluation result and take pre-defined policing actions on each packet:
Forwarding the packet if the evaluation result is "conforming."
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Dropping the packet if the evaluation result is "excess."
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Forwarding the packet with its precedence (which can be DSCP) re-marked if the evaluation result
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is "conforming."
Figure 8
31
shows an example of policing