Rate Limit - HP 1910 User Manual

Figure 478 GTS application
Device A

Rate limit

Rate limit is a traffic control method using token buckets. The rate limit of a physical interface specifies the
maximum rate for forwarding packets (including critical packets). Rate limit can limit all the incoming or
outgoing packets of physical interface.
Traffic evaluation and token bucket
A token bucket can be considered as a container holding a certain number of tokens. The system puts
tokens into the bucket at a set rate. When the token bucket is full, the extra tokens will overflow.
Figure 479 Evaluate traffic with the token bucket
The evaluation for the traffic specification is based on whether the number of tokens in the bucket can
meet the need of packet forwarding. If the number of tokens in the bucket is enough to forward the
packets (usually, one token is associated with a 1-bit forwarding authority), the traffic conforms to the
specification, and the traffic is called "conforming traffic"; otherwise, the traffic does not conform to the
specification, and the traffic is called "excess traffic".
A token bucket has the following configurable parameters:
• Mean rate—Rate at which tokens are put into the bucket, or the permitted average rate of traffic. It
is usually set to the committed information rate (CIR).
Device B
Physical link
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