D-Link DGS-1024D Switch User Manual


 
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which packets from various applications are mapped to and assigned a
priority. The illustration below shows how 802.1P priority queuing is
implemented 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 implement QoS, the user is required to instruct the Switch to examine
the header of a packet to see if it has the proper identifying tag tagged.
Then the user may forward these tagged packets to designated queues on
the Switch where they will be emptied, based on priority.
"The DUT support strict mode for 802.1p QoS. The untagged pkt will
follow the priority 0 to work (i.e. class 1)."
Understanding QoS
The Switch has four priority queues. These priority queues are labeled as 3,
the high queue to 0, the lowest queue. The eight priority tags, specified in
IEEE 802.1p are mapped to the Switch's priority tags as follows:
Priority 0 is assigned to the Switch's Q1 queue.
Priority 1 is assigned to the Switch's Q0 queue.
Priority 2 is assigned to the Switch's Q0 queue.
Priority 3 is assigned to the Switch's Q1 queue.
Priority 4 is assigned to the Switch's Q2 queue.
Priority 5 is assigned to the Switch's Q2 queue.
Priority 6 is assigned to the Switch's Q3 queue.