QoS - QoS Groups

In the context of Quality of Service, an internal QoS group is a feature that allows a device to assign an internal label to identify packets as members of a specific class. The distinctive characteristic of these QoS groups is that the label is not part of the packet header itself, and it is only locally significant, that is, only the device on which QoS groups are configured takes these QoS groups into account. QoS groups essentially provide a way to tag a packet for subsequent QoS action locally on the device, without explicitly marking or changing the packet.

A QoS group is identified and applied to the packet at ingress and is used at egress. It is assigned in an input policy to identify packets in an output policy.

https://forum.networklessons.com/t/why-do-we-need-qos-on-lan-switches/855/15?u=lagapides

https://www.cisco.com/en/US/docs/switches/metro/me3600x_3800x/trash/swqos.html#wp1051872