Line Rate; Configuring Traffic Policing - HP A5120 EI Series Configuration Manual

You can perform traffic shaping for the packets on the outgoing interface of Switch A to avoid
unnecessary packet loss. Packets exceeding the limit are cached in Switch A. Once resources are
released, traffic shaping takes out the cached packets and sends them out. All of the traffic sent to Switch
B conforms to the traffic specification defined in Switch B.

Line rate

NOTE:
Line rate rate-limits the outbound traffic.
The line rate of a physical interface specifies the maximum rate for forwarding packets (including critical
packets).
Line rate also uses token buckets for traffic control. With line rate configured on an interface, all packets
to be sent through the interface are handled by the token bucket at line rate. When the token bucket has
enough tokens, packets can be forwarded; otherwise, packets are put into QoS queues for congestion
management. The traffic passing the physical interface is controlled.
Figure 11 Line rate implementation
Packets to be sent via
this interface
In the token bucket approach for traffic control, bursty traffic can be transmitted if enough tokens are
available in the token bucket; if tokens are scarce, packets cannot be transmitted until efficient tokens are
generated in the token bucket. The token bucket approach limits the traffic rate to the rate for generating
tokens, and allows bursty traffic.
Line rate can only limit traffic rate on a physical interface, and traffic policing can limit the rate of a flow
on an interface. To limit the rate of all the packets on interfaces, using line rate is easier.

Configuring traffic policing

Follow these steps to configure traffic policing:
To do...
Enter system view
Put tokens into the token
bucket at the set rate
Queuing
Buffer queue
Use the command...
system-view
36
Packets sent
Token
bucket
Remarks
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