Chapter 4: Feature Description
Ethernet Features
Figure 57 Ingress Policing Model
CoS 1
CoS 2
CoS 3
Service
Point
Ethertype
Frame
Type
At each level (logical interface, service point, and service point + CoS), users can attach and
activate a rate meter profile. Users must create the profile first, then attach it to the interface,
service point, or service point + CoS.
Global Rate Meter Profiles
Users can define up to 250 rate meter user profiles. The following parameters can be defined for
each profile:
•
Committed Information Rate (CIR) – Frames within the defined CIR are marked Green and
passed through the QoS module. Frames that exceed the CIR rate are marked Yellow. The CIR
defines the average rate in bits/s of Service Frames up to which the network delivers service
frames and meets the performance objectives. Permitted values are 0 to 1 Gbps, with a
minimum granularity of 32Kbps.
•
Committed Burst Size (CBS) – Frames within the defined CBS are marked Green and passed
through the QoS module. This limits the maximum number of bytes available for a burst of
service frames in order to ensure that traffic conforms to the CIR. Permitted values are 2 to
128 Kbytes, with a minimum granularity of 2 Kbytes.
•
Excess Information Rate (EIR) – Frames within the defined EIR are marked Yellow and
processed according to network availability. Frames beyond the combined CIR and EIR are
marked Red and dropped by the policer. Permitted values are 0 to 1 Gbps, with a minimum
granularity of 32 Kbps.
•
Excess Burst Size (EBS) – Frames within the defined EBS are marked Yellow and processed
according to network availability. Frames beyond the combined CBS and EBS are marked Red
and dropped by the policer. Permitted values are 2 to 128 Kbytes, with a minimum granularity
of 2 Kbytes.
•
Color Mode – Color mode can be enabled (Color aware) or disabled (Color blind). In Color
aware mode, all frames that ingress with a CFI/DEI field set to 1 (Yellow) are treated as EIR
frames, even if credits remain in the CIR bucket. In Color blind mode, all ingress frames are
treated first as Green frames regardless of CFI/DEI value, then as Yellow frames (when there is
no credit in the Green bucket). A Color-blind policer discards any previous Color decisions.
•
Coupling Flag – If the coupling flag between the Green and Yellow buckets is enabled, then if
the Green bucket reaches the maximum CBS value the remaining credits are sent to the Yellow
bucket up to the maximum value of the Yellow bucket.
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