Traffic Shaping - HP A5120 EI Series Configuration Manual

Traffic policing is widely used in policing traffic entering the networks of internet service providers (ISPs).
Traffic policing can classify the policed traffic, and take pre-defined policing actions on each packet
depending on the evaluation result following these rules:
Forwarding the packet if the evaluation result is ―conforming‖

Dropping the packet if the evaluation result is ―excess‖

Forwarding the packet with its DSCP precedence re-marked if the evaluation result is ―conforming‖


Traffic shaping

NOTE:
Traffic shaping shapes the outbound traffic.
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
the buffered packets are sent at an even rate. Traffic shaping can result in additional delay, but traffic
policing does not.
Figure 9 Schematic diagram for GTS
Packets to be sent
through this interface
For example, in
packets from Switch A and drops packets exceeding the limit.
Figure 10 GTS application
Switch A
Tokens are put into the
bucket at the set rate
Packet
classification
Token
bucket
Figure 10, Switch A sends packets to Switch B. Switch B performs traffic policing on
Switch B
Physical link
Figure 9. When the token bucket has enough tokens,
Packets sent
Queue
Packets dropped
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