Edge-Core ECS4120-28F, Reference Manual, Page: 629 / 938

Chapter 23
| Quality of Service Commands
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committed-burst - Committed burst size (BC) in bytes.
(Range: 4000-16000000 bytes)
excess-burst - Excess burst size (BE) in bytes. (Range: 4000-16000000 bytes)
conform-action - Action to take when rate is within the CIR and BC. (There
are enough tokens in bucket BC to service the packet, packet is set green).
exceed-action - Action to take when rate exceeds the CIR and BC but is
within the BE. (There are enough tokens in bucket BE to service the packet,
the packet is set yellow.)
violate-action - Action to take when rate exceeds the BE. (There are not
enough tokens in bucket BE to service the packet, the packet is set red.)
transmit - Transmits without taking any action.
drop - Drops packet as required by exceed-action or violate-action.
new-dscp - Differentiated Service Code Point (DSCP) value. (Range: 0-63)
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 srTCM as defined in RFC 2697 meters a traffic stream and processes its
packets according to three traffic parameters – Committed Information Rate
(CIR), Committed Burst Size (BC), and Excess Burst Size (BE).
◆
The PHB label is composed of five bits, three bits for per-hop behavior, and two
bits for the color scheme used to control queue congestion. A packet is marked
green if it doesn't exceed the CIR and BC, yellow if it does exceed the CIR and
BC, but not the BE, and red otherwise.
◆
The meter operates in one of two modes. In the color-blind mode, the meter
assumes that the packet stream is uncolored. In color-aware mode the meter
assumes that some preceding entity has pre-colored the incoming packet
stream so that each packet is either green, yellow, or red. The marker (re)colors
an IP packet according to the results of the meter. The color is coded in the DS
field [RFC 2474] of the packet.
◆
The behavior of the meter is specified in terms of its mode and two token
buckets, C and E, which both share the common rate CIR. The maximum size of
the token bucket C is BC and the maximum size of the token bucket E is BE.