D-Link D DGS-3048 DGS-3048, Product Manual

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DGS-3048 Gigabit Ethernet Switch Manual
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Priority 4 is assigned to the Switch's Q4 queue.
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Priority 5 is assigned to the Switch's Q5 queue.
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Priority 6 is assigned to the Switch's Q6 queue.
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Priority 7 is assigned to the Switch's Q7 queue.
For strict priority-based scheduling, any packets residing in the higher priority queues are transmitted first. Multiple strict
priority queues empty based on their priority tags. Only when these queues are empty, are packets of lower priority
transmitted.
For weighted round-robin queuing, the number of packets sent from each priority queue depends upon the assigned weight.
For a configuration of eight CoS queues, A~H with their respective weight value: 8~1, the packets are sent in the following
sequence: A1, B1, C1, D1, E1, F1, G1, H1, A2, B2, C2, D2, E2, F2, G2, A3, B3, C3, D3, E3, F3, A4, B4, C4, D4, E4, A5,
B5, C5, D5, A6, B6, C6, A7, B7, A8, A1, B1, C1, D1, E1, F1, G1, H1.
For weighted round-robin queuing, if each CoS queue has the same weight value, then each CoS queue has an equal
opportunity to send packets just like round-robin queuing.
For weighted round-robin queuing, if the weight for a CoS is set to 0, then it will continue processing the packets from this
CoS until there are no more packets for this CoS. The other CoS queues that have been given a nonzero value, and
depending upon the weight, will follow a common weighted round-robin scheme.
Remember that the DGS-3048 has eight priority queues (and eight Classes of Service) for each port on the Switch.