R3303-HP HSR6800 Routers ACL and QoS Configuration Guide

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• 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).
Traffic shaping
Traffic shaping supports shaping the inbound traffic and the outbound traffic.
Traffic shaping limits the outbound traffic rate by buffering exceeding traffic. You can use traffic shaping
to adapt the traffic output rate on a device to the input traffic rate of its connected device to avoid packet
loss.
The difference between traffic policing and GTS is that packets to be dropped with traffic policing are
retained in a buffer or queue with GTS, as shown in Figure 10. W
hen enough tokens are in the token
bucket, the buffered packets are sent at an even rate. Traffic shaping can result in additional delay and
traffic policing does not.
Figure 10 GTS
For example, in Figure 11, Router B performs traffic policing on packets from Router A and drops packets
exceeding the limit. To avoid packet loss, you can perform traffic shaping on the outgoing interface of
Router A so packets exceeding the limit are cached in Router A. Once resources are released, traffic
shaping takes out the cached packets and sends them out.
Figure 11 GTS application
Router A
Router B
Physical link