Wes Eddy (Ohio University) and I have been working on quantifying the biases in RED queueing that occur depending on the units used to calculate the queue size and the marking probability (whether in terms of packets or in terms of the size of the packets).
At SIGCOMM 2002 Wes presented a poster detailing our work comparing RED byte and packet modes:
A paper detailing our results:
(Posted: Mon Aug 26, 2002; Updated: Mon Apr 28, 2003)