Reference Guide
Quality of service
Quality of service (QoS) manages the delay, jitter, bandwidth, and packet loss parameters on a network. OS10 devices examine each
received packet and place the packet into dierent classes of service (CoS) by assigning a trac class ID depending on the packet QoS
parameters.
QoS allows you to assign dierent behaviors to dierent trac classes. This QoS behavior tells the switch how to treat the trac as it
travels from the ingress interface, all the way until it is sent out the egress interface. You can assign dierent QoS behaviors to trac
classes including rate-limiting, rate-shaping, marking 802.1p or DSCP elds, queuing, and bandwidth management. QoS helps limit the rate
of control trac packets directed to the CPU.
Classify data trac
You can classify trac based on Layer 2 or Layer 3 header elds or on an incoming port. The packet header elds selected for matching are
called match criteria. Classication can be based on all or any of the match criteria. Dene class-maps for ingress classication of data
trac based on match criteria with a QoS type, and mark or tag classied trac with a trac class ID (qos-group). Use the queuing type
to dene class-maps for egress classication by matching the trac class ow IDs created during ingress classication (see Congure
class-map).
Classify control trac
Each set of pre-classied control trac towards the CPU is assigned a unique trac class ID. A control-plane type denes class-maps for
control-trac classication by matching the preassigned trac class ow IDs (qos-group).
Dene policy
Once the trac is classied into a class of service, dene policies to apply on selected trac classes. The policy represents the action (QoS
behavior) to be taken on the selected trac classes. Some actions are executed for ingress trac — called ingress policy actions. Allowed
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