Traffic Shaping - HP A6600 Configuration Manual

Traffic shaping

Traffic shaping provides measures to adjust the rate of outbound traffic actively. A typical traffic shaping
application limits the local traffic output rate according to the downstream traffic policing parameters.
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 9. When enough tokens are in the token bucket,
the buffered packets are sent at an even rate. Traffic shaping may result in additional delay and traffic
policing does not.
Figure 9 GTS schematic diagram
Tokens are put into the
bucket at the set rate
Packets to be sent
through this interface
Packets sent
Packet
classification
Token
bucket
Queue
Packets dropped
For example, in Figure 10, Router A sends packets to Router B. Router B performs traffic policing on packets
from Router A and drops packets exceeding the limit.
Figure 10 GTS application
Router A
Router B
Physical link
Perform traffic shaping for the packets on the outgoing interface of Router A to avoid unnecessary packet loss.
Packets exceeding the limit are cached in Router A. Once resources are released, traffic shaping takes out
the cached packets and sends them out. In this way, all the traffic sent to Router B conforms to the traffic
specification defined in Router B.
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