ZyXEL P-794H User Guide - Page 164

Strictly Priority Queuing, Weighted Fair Queuing, Finding Out More, Quality of Service QoS

Page 164 highlights

Chapter 14 Quality of Service (QoS) Strictly Priority Queuing Strictly Priority Queuing (SPQ) services queues based on priority only. As traffic comes into the P-794H, traffic on the highest priority queue, Q7 is transmitted first. When that queue empties, traffic on the next highest-priority queue, Q6 is transmitted until Q6 empties, and then traffic is transmitted on Q5 and so on. If higher priority queues never empty, then traffic on lower priority queues never gets sent. SP does not automatically adapt to changing network requirements. Weighted Fair Queuing Weighted Fair Queuing is used to guarantee each queue's minimum bandwidth based on its bandwidth weight (portion) (the number you configure in the Weight field) when there is traffic congestion. WFQ is activated only when a port has more traffic than it can handle. Queues with larger weights get more guaranteed bandwidth than queues with smaller weights. This queuing mechanism is highly efficient in that it divides any available bandwidth across the different traffic queues. By default, the weight for Q0 is 1, for Q1 is 2, for Q2 is 3, and so on. Guaranteed quantum is calculated as Queue Weight x 2048 bytes. Finding Out More See Section 14.7 on page 173 for advanced technical information on QoS. 164 P-794H User's Guide

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Chapter 14 Quality of Service (QoS)
P-794H User’s Guide
164
Strictly Priority Queuing
Strictly Priority Queuing (SPQ) services queues based on priority only. As traffic
comes into the P-794H, traffic on the highest priority queue, Q7 is transmitted
first. When that queue empties, traffic on the next highest-priority queue, Q6 is
transmitted until Q6 empties, and then traffic is transmitted on Q5 and so on. If
higher priority queues never empty, then traffic on lower priority queues never
gets sent. SP does not automatically adapt to changing network requirements.
Weighted Fair Queuing
Weighted Fair Queuing is used to guarantee each queue's minimum bandwidth
based on its bandwidth weight (portion) (the number you configure in the Weight
field) when there is traffic congestion. WFQ is activated only when a port has more
traffic than it can handle. Queues with larger weights get more guaranteed
bandwidth than queues with smaller weights. This queuing mechanism is highly
efficient in that it divides any available bandwidth across the different traffic
queues. By default, the weight for Q0 is 1, for Q1 is 2, for Q2 is 3, and so on.
Guaranteed quantum is calculated as Queue Weight x 2048 bytes.
Finding Out More
See
Section 14.7 on page 173
for advanced technical information on QoS.