H3C Technologies H3C SR8800 - Manual (Page 33)

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• Modifying the IP precedence of the packets whose evaluation result is “conforming” and
forwarding them
• Modifying the IP precedence of the packets whose evaluation result is “conforming” and delivering
them into the next-level Traffic policing
• Entering the next-level policing (you can set multiple traffic policing levels with each level focusing
on specific objects)
Traffic shaping
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 in traffic policing are
cached in a buffer or queue in GTS, as shown in Figure 8 . When the token bucket has enough tokens,
these cached packets are sent at an even rate. Traffic shaping may result in an additional delay, but
traffic policing does not.
Figure 8 GTS
For example, in Figure 9 , 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 9 GTS application