Lantech IES-3208C, User Manual

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6.9 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.
6.9.1 QoS Policy

Using the weight fair queue scheme
tThe 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.

Priority Type
There are 5 priority type selections available
—
Port-based , TOSonly , COS only ,
TOS first , and COS first . Disable means no priority type is selected.