Addendum

14
Quality of Service (QoS)
This chapter describes the QoS enhancements and contains the following sections:
• Classifying Packets Based on a Combination of DSCP Code Points and VLAN IDs
• Specifying Policy-Based Rate Shaping in Packets Per Second
• Managing Hardware Buffer Statistics
• Classifying Layer 2 Traffic on Layer 3 Interfaces
• RRoCE Overview
Specifying Policy-Based Rate Shaping in Packets Per
Second
The capability to configure rate shaping for QoS output policies in packets per second (pps) is supported
on the S6000 platform.
You can configure rate shaping that is applied to a QoS output policy in packets per second (pps), apart
from specifying the rate shaping value in bytes. You can also configure the peak rate, which is the
maximum permissible rate for the packets, and the committed rate, which is the minimum confirmed rate
that is maintained for the packets, in kilobits per second (Kbps) or pps.
Committed rate refers to the guaranteed bandwidth for traffic entering or leaving the interface under
normal network conditions. When traffic propagates at an average rate that is less than or equal to the
committed rate, it is considered to be green-colored or coded. When the transmitted traffic falls below
the committed rate, the bandwidth that is not used by any traffic that is traversing the network is
aggregated to form the committed burst size. Traffic is considered to be green-colored up to a point at
which the unutilized bandwidth does not exceeded the configured committed burst size.
Peak rate refers to the maximum rate for traffic arriving or exiting an interface under normal traffic
conditions. Peak burst size indicates the maximum size of unused peak bandwidth that is aggregated.
This aggregated bandwidth enables brief durations of burst traffic that exceeds the peak rate and
committed burst.
In releases of Dell Networking OS earlier than Release 9.3.0.0, you can configure only the maximum
shaping attributes, such as the peak rate and peak burst settings. You can now specify the committed or
minimum burst and committed rate attributes. The committed burst and committed rate values can be
defined either in bytes or packets per second.
You can use the rate-shape pps peak-rate burst-packets command in the QoS Policy Out
Configuration mode to configure the peak rate and burst size as a measure of pps. Alternatively, you can
use the rate shape kbps peak-rate burst-KB command to configure the peak rate and peak
burst size as a measure of bytes.
Similarly, you can use the rate-shape pps peak-rate burst-packets committed pps
committed-rate
burst-packets command in the QoS Policy Out Configuration mode to configure
the committed rate and committed burst size as a measure of pps. Alternatively, you can use the rate
shape kbps peak-rate
burst-KB committed kbps committed-rate burst-KB command to
configure the committed rate and committed burst size as a measure of bytes. If you configure the peak
Quality of Service (QoS)
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