A Comparative Study of Active Queue Management Schemes

Active Queue Management (AQM) schemes are a class of queueing algorithms designed to surmount some of the shortcomings of classic Drop-Tail queues in best-effort networks. Much recent work has focused on improving AQM performance through alternate approaches: in excess of 50 schemes have been proposed since 1999 alone. This study details a simulationbased evaluation and comparison of a subset of these schemes. It utilises a specially designed framework which builds on the NS2 simulator. The schemes chosen have been designed to allow for implementation and incremental deployment on routers of the existing Internet architecture. The evaluation methodology adopted enables the direct comparison of AQM schemes, clearly highlighting their similarities and differences. It thus addresses the current need for an unbiased comparative evaluation of the various proposals. Such work should encourage faster adoption of improved AQM algorithms in Internet routers.