Lantech IES-2008B-DNV, Руководство пользователя

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6.25 QoS
Quality of Service (QoS) is the ability to provide different priority to different applications,
users or data flows, or to guarantee a certain level of performance to a data flow. QoS
guarantees are important if the network capacity is insufficient, especially for real-time
streaming multimedia applications such as voice over IP or Video Teleconferencing,
since these often require fixed bit rate and are delay sensitive, and in networks where
the capacity is a limited resource, for example in cellular data communication. In the
absence of network congestion, QoS mechanisms are not required.
6.25.1 Global Settings
Here you can choose to use an 8-4-2-1 queuing scheme or a strict priority scheme, or
select the priority type to configure QoS policy.

Qos Policy: Select the QoS policy rule.

Using the 8,4,2,1 weight fair queue scheme: The switch will follow 8:4:2:1
rate to process priority queue from High to lowest queue. For example, while
the system processing, 1 frame of the lowest queue, 2 frames of the low queue,
4 frames of the middle queue, and 8 frames of the high queue will be
processed at the same time in accordance with the 8,4,2,1 policy rule.

Use a strict priority scheme: Always the higher queue will be processed first,
except the higher queue is empty.

Priority Type: There are 5 priority type selections available
—
Port-based , TOS
only , COS only , TOS first , and COS first . Disable means no priority type is
selected.

Click
Apply
to have the configuration take effect.