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  • Research Article
  • Open Access

Traffic Agents for Improving QoS in Mixed Infrastructure and Ad Hoc Modes Wireless LAN

  • 1Email author,
  • 2,
  • 3,
  • 2 and
  • 2
EURASIP Journal on Wireless Communications and Networking20062006:094235

Received: 12 July 2005

Accepted: 28 December 2005

Published: 7 March 2006


As an important complement to infrastructured wireless networks, mobile ad hoc networks (MANET) are more flexible in providing wireless access services, but more difficult in meeting different quality of service (QoS) requirements for mobile customers. Both infrastructure and ad hoc network structures are supported in wireless local area networks (WLAN), which can offer high data-rate wireless multimedia services to the mobile stations (MSs) in a limited geographical area. For those out-of-coverage MSs, how to effectively connect them to the access point (AP) and provide QoS support is a challenging issue. By mixing the infrastructure and the ad hoc modes in WLAN, we propose in this paper a new coverage improvement scheme that can identify suitable idle MSs in good service zones as traffic agents (TAs) to relay traffic from those out-of-coverage MSs to the AP. The service coverage area of WLAN is then expanded. The QoS requirements (e.g., bandwidth) of those MSs are considered in the selection process of corresponding TAs. Mathematical analysis, verified by computer simulations, shows that the proposed TA scheme can effectively reduce blocking probability when traffic load is light.


  • Access Point
  • Mobile Station
  • Wireless Local Area Network
  • Wireless Multimedia
  • Mode Wireless


Authors’ Affiliations

Department of Electronic and Electrical Engineering, University College London, London, United Kingdom
School of Engineering and Design, Brunel University, Uxbridge, United Kingdom
Institute of Communications Engineering, National Sun Yat-Sen University, Kaohsiung, Taiwan


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© Yang Yang et al. 2006

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