Open Access

Bandwidth Optimization in Centralized WLANs for Different Traffic Types

EURASIP Journal on Wireless Communications and Networking20072007:023917

Received: 31 May 2006

Accepted: 10 January 2007

Published: 29 March 2007


Allocating bandwidth between different forms of coexisting traffic (such as web-browsing, streaming, and telephony) within a wireless LAN is a challenging and interesting problem. Centralized coordination functions in wireless LANs offer several advantages over distributed approaches, having the benefit of a system overview at the controller, but obtaining a stable configuration of bandwidth allocation for the system is nontrivial. We present, review, and compare different mechanisms to achieve this end, and a number of different means of obtaining the configurations themselves. We describe an analytical model of the system under consideration and present two mathematical approaches to derive solutions for any system configuration and deployment, along with an adaptive feedback-based solution. We also describe a comprehensive simulation-based model for the problem, and a prototype that allows comparison of these approaches. Our investigations demonstrate that a self-adaptive dynamic approach far outperforms any static scheme, and that using a mathematical model to produce the configurations themselves confers several advantages.


Authors’ Affiliations

Telecommunications Research Laboratory, Toshiba Research Europe Ltd.


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© R. J. Haines et al. 2007

This article is published under license to BioMed Central Ltd. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.