WRED (Weighted Random Early Detection)

Hello Ranganna

When WRED calculates the average queue size, it does so by calculating the actual size of the real queue. Specifically, the average is calculated periodically every few milliseconds. It uses the following formula:


  • o is the old average calculated the previous time
  • n is the weight factor you configure
  • c is the current queue size

The maximum size of the physical queue will depend on what kind of interface we’re talking about and what platform it is functioning on.

I hope this has been helpful!