Extreme Networks ExtremeWare XOS 10.1, Manual

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Traffic Groupings
ExtremeWare XOS 10.1 Concepts Guide 85
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When configured to do so, the priority of a QoS profile can determine the 802.1p bits used in the
priority field of a transmitted packet (described later).
— The priority of a QoS profile determines the DiffServ code point value used in an IP packet when
the packet is transmitted (described later).
A QoS profile does not alter the behavior of the switch until it is assigned to a traffic grouping. Recall
that QoS profiles are linked to hardware queues. There are multiple hardware queues per physical port.
By default, a QoS profile links to the identical hardware queue across all the physical ports of the
switch.
The default QoS profiles cannot be deleted. Also by default, a QoS profile maps directly to a specific
hardware queue across all physical ports. The settings for the default QoS parameters are summarized
in Table 12.
Traffic Groupings
After a QoS profile has been modified for bandwidth and priority, you assign traffic a grouping to the
profile. A traffic grouping is a classification of traffic that has one or more attributes in common. Traffic is
typically grouped based on the applications discussed starting on page 82.
Traffic groupings are separated into the following categories for discussion:
• Explicit packet class of service information, such as 802.1p or DiffServ (IP TOS)
• Physical configuration (physical source port association)
In the event that a given packet matches two or more grouping criteria, there is a predetermined
precedence for which traffic grouping will apply. In general, the more specific traffic grouping takes
precedence. By default, all traffic groupings are placed in the QoS profile Qp1. The supported traffic
groupings are listed in Table 13. The groupings are listed in order of precedence (highest to lowest). The
four types of traffic groupings are described in detail on the following pages.
Table 12: QoS Parameters
Profile Name Hardware Queue Priority
Minimum
Bandwidth Maximum
Bandwidth
Qp1 Q0 Low 0% 100%
Qp2 Q1 Lowhi 0% 100%
Qp3 Q2 Normal 0% 100%
Qp4 Q3 Normalhi 0% 100%
Qp5 Q4 Medium 0% 100%
Qp6 Q5 Mediumhi 0% 100%
Qp7 Q6 High 0% 100%
Qp8 Q7 Highhi 0% 100%
Table 13: Traffic Groupings by Precedence
Explicit Packet Class of Service Groupings