In this paper we present new model-based controllers for active queue management (AQM) supporting TCP ows. Our control design is based on linearization of a previously developed TCP model using uid ow and stochastic di erential equations. An AQM using a simple PI controller is shown to signi cantly outperform RED AQM. However, we show that both AQMs are unable to maintain performance as the num...

Wireless access points act as bridges between wireless and wired networks. Since the actually available bandwidth in wireless networks is much smaller than that in wired networks, there is a bandwidth disparity in channel capacity which makes the access point a significant network congestion point. The recently proposed active queue management (AQM) is an effective method used in wired network ...

Analytical and empirical studies have shown that self-similar trafic can have detrimental impact on network performance including amplified queuing delay and packet loss ratio. On the flip side, the ubiquity of scale-invariant burstiness observed across diverse networking contexts can be exploited to better design resource control algorithms. In this paper, we explore the issue of exploiting tr...

One of the major component in a QoS-enabled network is active queue management (AQM). Over the last decade numerous AQM schemes have been proposed in the literature. However, much recent work has focused on improving AQM performance through alternate approaches. This study focuses on an unbiased comparative evaluation of the various proposals. The evaluation methodology adopted is the following...

Active Queue Management (AQM) is the process of signaling Transmission Control Protocol (TCP) sources from core routers with the objective of managing queue utilization and delay. AQM methods can be classified into two main classes, namely, non-control theoretic-Random Early Detection(RED) and its variants and control theoretic-Proportional (P), Proportional Integral (PI) controllers. Shortcomi...

Internet congestion control and congestion avoidance have been active research interests in the area of networking (see, for example [1] [2] [3]) during the last two decades. It has two components: (1) the end-to-end congestion control protocol, such as TCP [4], and (2) an active queue management (AQM) scheme implemented in routers. AQM signals congestion by discarding or marking packets. When ...

In this paper we present a virtual queue based active queue management scheme called Adaptive Virtual Buffer(AVB). We study its properties in satisfying the QoS requirement such as low packet loss rate and high throughput; its ability in maintaining stable queue length under various network configurations such as the number of connections and round trip delay; and its robustness in the presence...

Internet over the past few years has undergone dramatic changes in terms of scale, penetration rate and the diversity of applications. The demand for continuous network connectivity is profilerating. Moreover, it has been observed that the usage of real time applications like Voice over IP (VoIP) and Live Streaming has increased drastically. Passive Queue Management (PQM) mechanisms in the rout...

Congestion is an important issue which researchers focus on in the Transmission Control Protocol (TCP) network environment. To keep the stability of the whole network, congestion control algorithms have been extensively studied. Queue management method employed by the routers is one of the important issues in the congestion control study. Active queue management (AQM) has been proposed as a rou...

A novel logic-based switching control strategy for internet congestion is applied for asymptotically stabilizing a class of transmission control protocol (TCP) networks at a desired operating point. We consider the problem of output feedback control instead of state-feedback control. The uncertainties with respect to the number of the active TCP sessions are considered. A high gain observer for...