Computer
Amar A. Mahawish; Hassan Jalee.l Hassan
Abstract
The performance of the Internet is significantly impacted by network congestion. Because of the internet's current rapid growth, congestion could increase and cause more packets to be dropped. The Transmission Control Protocol (TCP) connection is used as the reliable transmission of packets which has ...
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The performance of the Internet is significantly impacted by network congestion. Because of the internet's current rapid growth, congestion could increase and cause more packets to be dropped. The Transmission Control Protocol (TCP) connection is used as the reliable transmission of packets which has a Drop Tail (DT) mechanism since congestion DT signals occur only when the queue has become full. The Random Early Detection algorithm mechanism can be developed as congestion control which eliminates the drawback of a tail drop queue full. The Red algorithm also has problems dealing with different numbers of connections due to fix parameter tuning. In this study, the EXhaustive search used with the RED algorithm to develop the EX-RED algorithm. Based on network performance metrics such as packet drop, delay, and throughput, the developed algorithm adjusts the default RED parameter to find the best of them. When the number of TCP connections changes, the exhaustive search used systematically enumerates all possible states of the parameter. The simulation results showed that the EXRED improved performance of the network as compared with the other five algorithms (GRED, RED, ARED, NLRED, and NLGRED) by decreasing delay and dropped packets and increasing packet throughput.
Dr. Farooq Al- doraiee; Salih Al-Qaraawi; Hassan J. Hassan
Volume 13, Issue 1 , April 2013, , Page 9-17
Abstract
Abstract – Internet represents a shared resource wherein users contend for the finite
network bandwidth. Contention among independent user demands can result in
congestion, which, in turn, leads to long queuing delays, packet losses or both.
Congestion control regulates the rate at which traffic ...
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Abstract – Internet represents a shared resource wherein users contend for the finite
network bandwidth. Contention among independent user demands can result in
congestion, which, in turn, leads to long queuing delays, packet losses or both.
Congestion control regulates the rate at which traffic sources inject packets into a
network to ensure high bandwidth utilization while avoiding network congestion. In the
current Internet, there are two mechanisms which deal with congestion; the end-to-end
mechanism which is achieved by the Transmission Control Protocol (TCP) and the
intermediate nodes algorithms such as Active Queue Management (AQM) in routers.
In this paper, a combined model of TCP and AQM (TCP/AQM) is formulated and
first simulated without a controller. The results show that it is unable to track the desired
queue size. So, to get better tracking performance, an adaptive PID controller based on
wavelet network (AWNPID) is used as AQM in the router queue. The non-adaptive PID
controller is also demonstrated, and its weakness to the network dynamic changes is
compared to the robustness of adaptive controller (AWNPID). The analytical results for
linearized TCP/AQM model are presented in MATLAB version 7.0.
