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802.1P and QoS
The DGS-1024T and DGS-1016T Switches support 802.1p priority queuing
Quality of Service . The imp le mentation of QoS (Qua lity of Se rvice) and
benefits of using 802.1p priority queuing are described here.
Advantages of QoS
QoS is an imple mentation of the IEEE 802.1p standard that allows network
administrators a method of reserving bandwidth for important functions that
require a large bandwidth or have a high priority, such as VoIP (voice-over
Internet Protocol), web browsing applications, file server applications or video
conferencing. Not only can a larger bandwidth be created, but other less
critica l tra ffic can be limited, so bandwidth can be saved. The Switch has
separate hardware queues on every physical port to which packets fro m
various applications are mapped to and assigned a priority. The illustration
below shows how 802.1P priority queuing is imple mented on the Switch. The
eight IEEE 802.1P priority levels defined by the standard are mapped to the
four class queues used in the Switch.
Mapping QoS on the Switch
The picture above shows the default priority setting for the Switch. Class-3 has
the highest priority of the four priority queues on the Switch. In order to
imple ment QoS, the user is required to instruct the Switch to exa mine the
