SignaMax SC30010, Справочное руководство CLI

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Chapter 20
| Quality of Service Commands
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police rate
This command defines an enforcer for classified traffic based on the metered
flow rate. Use the
no form to remove a policer.
Syntax
[ no ] police rate committed-rate
committed-rate - Committed information rate in kilobits per second.
(Range: 16-1000000 kbps at a granularity of 64 kbps or maximum
port speed, whichever is lower)
Default Setting
None
Command Mode
Policy Map Class Configuration
Command Usage
◆ You can configure up to 16 policers (i.e., class maps) for ingress ports.
◆ The committed-rate cannot exceed the configured interface speed.
◆ Policing is based on a token bucket, where bucket depth is the maximum
burst before the bucket overflows, and the average rate tokens that are
added to the bucket is by specified by the
committed-rate option. Note that
the token bucket functions similar to that described in RFC 2697 and RFC
2698.
◆ The behavior of the meter is specified in terms of one token bucket (C), the
rate at which the tokens are incremented (CIR – Committed Information
Rate), and the maximum size of the token bucket (BC – Committed Burst
Size).
The token bucket C is initially full, that is, the token count Tc(0) = BC. Thereafter,
the token count Tc is updated CIR times per second as follows:
■
If Tc is less than BC, Tc is incremented by one, else
■
Tc is not incremented.
When a packet of size B bytes arrives at time t, the following happens:
■
If Tc(t)-B

0, the packet is green and Tc is decremented by B down to the
minimum value of 0,
■
else the packet is red and Tc is not decremented.