A new algorithm for controlling the mean queue length in a buffer with time varying arrival rate

Abstract

Active Queue Management (AQM) algorithms play an important role in fair bandwidth allocation. In order to guarantee Quality of Service (QoS) to diverse Internet services, it is important to employ effective buffer management schemes at Internet routers. Controlling the size of the buffer is determined by the dynamics of TCP's congestion control algorithms. Therefore, effectively constraining the mean queue length to a specified level is a key QoS requirement. The goal is to make sure that the mean queue length is maintained at a specified level when a link is congested. This paper presents a control strategy that operates on a buffer which incorporates a moveable threshold. An algorithm is developed to control the mean queue length by dynamically adjusting the threshold, which, in turn, controls the effective arrival rate, by randomly dropping packets.