Traffic Policing And Traffic Shaping Configuration; Traffic Policing And Traffic Shaping Overview; Traffic Evaluation And Token Bucket - H3C S5810 Series Operation Manual

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Traffic Policing and Traffic Shaping Configuration

When configuring traffic classification, traffic policing, and traffic shaping, go to these sections for
information you are interested in:

Traffic Policing and Traffic Shaping Overview

Traffic Policing, GTS and Line Rate Configuration
Displaying and Maintaining Traffic Policing, GTS and Line Rate
Traffic Policing and GTS Configuration Examples
Traffic Policing and Traffic Shaping Overview
If user traffic is not limited, burst traffic will make the network more congested. Therefore it is necessary
to limit user traffic in order to better utilize the network resources and provide better services for more
users. For example, you can configure a flow to use only the resources committed to it in a time range,
thus avoiding network congestion caused by burst traffic.
Traffic policing and generic traffic shaping (GTS) limit traffic rate and resource usage according to traffic
specifications. The prerequisite for traffic policing or GTS is to know whether a traffic flow has exceeded
the specification. If yes, proper traffic control policies are applied. Generally, token buckets are used to
evaluate traffic specifications.

Traffic Evaluation and Token Bucket

Token bucket features
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.
Evaluating 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 (generally, 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: At which tokens are put into the bucket, namely, the permitted average rate of traffic. It
is usually set to the committed information rate (CIR).
Burst size: the capacity of the token bucket, namely, the maximum traffic size that is permitted in
each burst. It is usually set to the committed burst size (CBS). The set burst size must be greater
than the maximum packet size.
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