ZyXEL ES-2108PWR User Guide - Page 135
Queuing Method
View all ZyXEL ES-2108PWR manuals
Add to My Manuals
Save this manual to your list of manuals |
Page 135 highlights
CHAPTER 18 Queuing Method This chapter introduces the queuing methods supported. 18.1 Queuing Method Overview 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. Queuing algorithms allow switches to maintain separate queues for packets from each individual source or flow and prevent a source from monopolizing the bandwidth. Table 40 Physical Queue Priority QUEUE PRIORITY Q3 4 (highest) Q2 3 Q1 2 Q0 1 (lowest) 18.1.1 Strict Priority Queuing (SPQ) Strict Priority Queuing (SPQ) services queues based on priority only. As traffic comes into the Switch, traffic on the highest priority queue, Q3 is transmitted first. When that queue empties, traffic on the next highest-priority queue, Q2 is transmitted until Q2 empties, and then traffic is transmitted on Q1 and so on. If higher priority queues never empty, then traffic on lower priority queues never gets sent. SPQ does not automatically adapt to changing network requirements. 18.1.2 Weighted Round Robin Scheduling (WRR) Round Robin Scheduling services queues on a rotating basis and is activated only when a port has more traffic than it can handle. A queue is a given an amount of bandwidth irrespective of the incoming traffic on that port. This queue then moves to the back of the list. The next queue is given an equal amount of bandwidth, and then moves to the end of the list; and so on, depending on the number of queues being used. This works in a looping fashion until a queue is empty. ES-2108 Series User's Guide 135