ZyXEL Communications GS2200-24P Series, User Manual, Page: 187 / 360

GS2200-24/24P User’s Guide
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Queuing Method
22.1 Overview
This chapter introduces the queuing methods supported.
Queuing is used to help solve performance degradation when there is network
congestion. Use the Queuing Method screen to configure queuing algorithms for
outgoing traffic. See also Priority Queue Assignment in Switch Setup and
802.1p Priority in Port Setup for related information.
22.1.1 What You Can Do
Use the Queueing Method screen ( Section 22.2 on page 188 ) set priorities for
the queues of the Switch.
This distributes bandwidth across the different traffic queues.
22.1.2 What You Need to Know
Queuing algorithms allow switches to maintain separate queues for packets from
each individual source or flow and prevent a source from monopolizing the
bandwidth.
Strictly Priority Queuing
Strictly Priority Queuing (SPQ) services queues based on priority only. As traffic
comes into the Switch, 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