HP VPN Firewall Appliances Network Management Configuration Guide

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• EBS—Size of bucket E, which specifies the transient burst of traffic that bucket E can forward.
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.
• 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.
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. Figure 228 sho
ws an example of poli
cing
outbound traffic on an interface.
Figure 228 Traffic policing
Traffic policing is widely used in policing traffic entering the networks of ISPs. It can classify the policed
traffic and take predefined policing actions on each packet depending on the evaluation result:
• Forwarding the packet if the evaluation result is "conforming."
• Dropping the packet if the evaluation result is "excess."
• Forwarding the packet with its IP precedence re-marked if the evaluation result is "conforming."
• Delivering the packet to next-level traffic policing with its IP precedence re-marked if the evaluation
result is "conforming."
• Entering the next-level policing (you can set multiple traffic policing levels each focused on specific
objects).