An Active Queue Management Scheme for Internet

In this paper, we propose a new active queue management algorithm, called Average Rate Early Detection (ARED). An ARED gateway measures/uses the average packet enqueue rate as a congestion indicator, and judiciously signals end hosts of incipient congestion, with the objective of reducing packet loss ratio and improving link utilization. We show (via simulation in ns-2) that the performance of ARED is better than RED and comparable to BLUE in terms of packet loss rate and link utilization. We also explore the use of ARED in the context of Diierentiated Services architecture. We rst show analytically that the widely referenced queue management mechanism, RED with in and out (RIO) cannot achieve throughput assurance and proportional bandwidth sharing. We then extend ARED and propose a new queue management mechanism, called ARED with in and out (AIO), in the assured services architecture. To share surplus bandwidth in a rate-proportional manner, we incorporate into AIO the derived analytic results, and propose a enhanced version of AIO, called the diierentiated-rate AIO (DAIO) mechanism. Finally we validate the design of AIO and DAIO by comparing their performance against that of RIO and BLUE with in and out (BIO). Any opinions, ndings, and conclusions or recommendations expressed in this paper are those of the authors and do not necessarily reeect the views of the NSF.