WRED parameters

Determine the following parameters before configuring WRED:

• The upper threshold and lower threshold—When the average queue size is smaller than the lower threshold, no packet is dropped. When the average queue size is between the lower threshold and the upper threshold, the packets are dropped at random. The longer the queue is, the higher the drop probability is. When the average queue size exceeds the upper threshold, subsequent packets are dropped.

• The exponent used for average queue size calculation—The bigger the exponent is, the less sensitive the average queue size is to real-time queue size changes.

• Denominator for drop probability calculation—The bigger the denominator is, the smaller the calculated drop probability is.