Removal of the Noise Source Inherent to AQM

Abstract

implementations drop packets randomly as a function of the average queue fill. Over a short window of time, all packets are dropped with virtually equal probability. This causes the actual number of dropped packets to vary according to a binomial distribution, and can result in a significant difference between the actual numbers of dropped packets and the expected. As a result, this introduces unnecessary noise to the system which substantially affects variations in queue fill. A new approach to calculating dropping probabilities is proposed here that adapts the dropping probability over a window of packets and ensures that the number of packets that are actually dropped is virtually equal to the number that are expected to be dropped. It is shown here that this substantially reduces unnecessary variance in queue fill. Index Terms—Active queue management, random early dropping. I