Chapter 6
Policing Traffic
The two-rate three-color marker uses a token bucket algorithm to manage the maximum rate of traffic.
The token bucket algorithm can use the values you specify to determine the maximum rate of traffic
allowed on an interface at a given moment in time. All traffic entering or leaving an interface affects the
token bucket algorithm, depending on whether the two-rate policer is configured on an inbound or
outbound interface. The token bucket algorithm is useful in managing network bandwidth when large
packets are sent in the same traffic stream. For more information about the token bucket algorithm, see
the
To mark traffic without using a policer, see
Feature History for the Two-Rate Color Marker
Cisco IOS Release
Release 12.2(27)SBB The two-rate three-color marker feature was introduced on
Release 12.2(31)SB2
Configuration Commands for the Two-Rate Color Marker
The commands used to configure the two-rate color marker are:
•
•
police Command (Two-Rate)
To configure traffic policing using the committed information rate (CIR) and the peak information rate
(PIR), use the police command in policy-map class configuration mode. To remove two-rate traffic
policing from the configuration, use the no form of this command. By default, this command is disabled.
police {cir cir} [bc] burst-normal [pir pir] [be] peak-burst [conform-action action]
[exceed-action action] [violate-action action]
no police {cir cir} [bc] burst-normal [pir pir] [be] peak-burst [conform-action action]
[exceed-action action] [violate-action action]
Syntax Description
cir cir
bc burst-normal
OL-7433-09
"Metering Traffic and Token Buckets" section on page
Description
the router.
This feature was introduced on the PRE3 to allow you to
police traffic on the L2TP access concentrator (LAC) based
on the value of a packet's IP DSCP bits.
police Command (Two-Rate), page 6-9
police percent Command, page 6-11
Committed information rate (CIR). Indicates an average rate at which the
policer meters traffic. CIR is based on the interface shape rate. The cir
specifies the CIR value in bits per second. Valid values are from 8000 to
2,488,320,000 bits per second.
(Optional) Specifies the normal or committed burst (bc) size used by the
first token bucket for policing. The burst-normal specifies the bc value in
bytes. Valid values are from 1 to 512,000,000. The default is 9,216 bytes.
For more information, see the
section on page
Two-Rate Three-Color Marker for Traffic Policing
6-18.
Chapter 7, "Marking Traffic."
"Committed Bursts and Excess Bursts"
6-21.
Cisco 10000 Series Router Quality of Service Configuration Guide
Required PRE
PRE2
PRE3
6-9