Adaptive tuning of drop-tail buffers for reducing queueing delays

Internet router buffers are used to accommodate packets that arrive in bursts and to maintain high utilization of the egress link. Such buffers can lead to large queuing delays. We propose a simple algorithm, active drop-tail (ADT), which regulates the queue size, based on prevailing traffic conditions, to a minimum size that still allows for a desired (high) level of utilization. Packet level ns2 simulations are provided to show that adaptive drop-tail achieves significantly smaller queues than current approaches at the expense of 1-2% of the link utilization.