MDG: MEASUREMENT-DRIVEN GUIDELINES FOR 802.11 WLAN DESIGN

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MDG MEASUREMENT-DRIVEN GUIDELINES FOR 802.11
WLAN DESIGN

• Ioannis Broustis, Konstantina Papagiannaki,
  Srikanth V. Krishnamurthy, Michalis Faloutsos,
  Vivek Mhatre
• ACM MOBICOM 2007

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Goal Improve WLAN network performance

• Three functions to improve network performance in
  dense WLANs
• Frequency selection
• Provides spatial separation between interfering
  APs
• User association
• Provides load balancing among APs
• Power control
• APs shrink their cells to facilitate higher
  spatial reuse of spectrum

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Frequency Selection

• Neighbor Access Points (APs) select different
  frequencies in order to mitigate interference
  from each other

Cell of B
Cell of A
Channel 6
Channel 11
B
A
AP
AP
Channel 6
Channel 6
Inter-cell Contention A cannot transmit because
B is transmitting
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User Association

• Users select less-loaded Access Points (APs) in
  order to get more throughput

A
B
AP
AP
C
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Power Control

• APs shrink their overlapping cells in order to
  reduce interference and improve spatial reuse

A
B
AP
AP
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Problem statement

• Which are the functions that should be applied in
  a specific scenario?
• In what sequence should they be applied?
• High level objective to maximize a fair notion
  of aggregate network throughput

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Previous Work

• Most studies have tried to optimize one of these
  functions
• No studies on the interdependencies between all
  three functions
• A. Mishra, V. Shrivastava, D. Agarwal, S.
  Banerjee. Distributed Channel Management in
  Uncoordinated Wireless Environments. MOBICOM
  2006.
• N. Ahmed, S. Keshav. SMARTA A Self-Managing
  Architecture for Thin Access Points. CoNEXT 2006.
  
• K. Sundaresan, K. Papagiannaki. The Need for
  Cross-Layer Information in Access Point Selection
  Algorithms. IMC 2006.
• A. Mishra, V. Brik, S. Banerjee, A. Srinivasan,
  W. Arbaugh. A Client-Driven Approach for Channel
  Management in Wireless LANs. INFOCOM 2006.
• A. Kumar, V. Kumar. Optimal Association of
  Stations and APs in an IEEE 802.11 WLAN. NCC
  2005.
• T. Korakis, O. Ercetin, S. V. Krishnamurthy, L.
  Tassiulas, S. Tripathi. Link Quality Based
  Association Mechanism in IEEE 802.11h Compliant
  Wireless LANs. RAWNET 2005.
• B. Leung, K. Kim. Frequency Assignment for IEEE
  802.11 Wireless Networks. VTC 2003.
• Y. Bejerano, S. Han, L. Li. Fairness and Load
  Balancing in Wireless LANs Using Association
  Control. MOBICOM 2004.