In this paper, we apply an anti-windup scheme for improving the performance of a conventional ProportionalIntegral (PI) controller for Active Queue Management (AQM) supporting TCP flows. When a PI controller is used for AQM, the “windup” phenomenon of the integral action can cause performance degradation because the packet drop probability is limited between 0 and 1. Therefore we model TCP/AQM ...

The problem of overbuffering in today’s Internet (termed as bufferbloat) has recently drawn a great amount of attention from the research community. This has led to the development of various active queue management (AQM) schemes. The last years have seen a lot of effort to show the benefits of AQMs over simple tail-drop queuing and to encourage deployment. Yet it is still unknown to what exten...

Consider an M/G/1 queue which is idle at time 0. The number of customers sampled at an independent exponential time is shown to have the same geometric distribution under the preemptive resume last in first out (LIFO) and the processor sharing (PS) disciplines. Hence, the marginal distribution of the queue length at any time is identical for both disciplines. We then give a detailed analysis of...

Routers handle data packets from sources unresponsive to TCP’s congestion avoidance feedback. We are interested in the impact these sources have on AQM’s control of long-lived TCP traffic. In this paper, we combine models of TCP/AQM dynamics with models of unresponsive traffic to analyze the effects on AQM performance.

Dewan Md. Emdadul Hoque ([email protected]) Muntasirur Rahman ([email protected]) Sk. Masum Billah ([email protected]) Michael Savic ([email protected]) AQM Rezaul Karim ([email protected]) Enayet Karim Chowdhury ([email protected]) Altaf Hossain ([email protected]) SAJ Md. Musa ([email protected]) Harish Kumar ([email protected]) Sudhansh Malhotra ([email protected]....

The Adaptive RED proposed by Feng et al . [5] is shown to have small packet delay and queue length variation for long-life TCP traffic such as FTP connection with a large file size. However, a great portion of Internet traffic is shortlife web and UDP traffic. Most web traffic has a small file size and its TCP session is mainly operated in the slow start phase with a small congestion window siz...

The two approaches of congestion control i. e. source based approach and router based approach have their own limitations. In source based approach, It is difficult to get correct location of congestion and without proper admission control; it would be difficult to effectively manage the congestion problem. So both approaches have to work in coordination for effectively control the congestion p...

At Oakland 2005, Murdoch and Danezis described an attack on the Tor anonymity service that recovers the nodes in a Tor circuit, but not the client. We observe that in a peer-to-peer anonymity scheme, the client is part of the circuit and thus the technique can be of greater significance in this setting. We experimentally validate this conclusion by showing that “circuit clogging” can identify c...

Cuvinte cheie. Managementul cozilor de aşteptare, filtru median, probabilitate de rejectare, întârziere. Rezumat. Articolul evaluază performanţele unui algoritm RED (random early detection) modificat care utilizează un filtru median în locul unui filtru liniar pentru calculul probabilităţii de rejectare a pachetelor. Simulările ilustrează faptul că performanţa reţelei creşte prin utilizarea fil...

The performance of a Transmission Control Protocol (TCP) for a system with N connections sharing a common Active Queue Management (AQM) is analyzed for both AdditiveIncrease Multiplicative-Decrease (AIMD) and MultiplicativeIncrease Multiplicative-Decrease (MIMD) control mechanisms, where reduction signals follow either a cyclic or a probabilistic polling-type procedure. The Laplace-Stieltjes Tr...