Mobile Networks and Applications

, Volume 14, Issue 4, pp 523–538 | Cite as

VoIP over Wi-Fi Networks: Performance Analysis and Acceleration Algorithms

  • Yeonsik JeongEmail author
  • Sandeep Kakumanu
  • Cheng-Lin Tsao
  • Raghupathy Sivakumar


The expected VoIP call capacity in a one hop IEEE 802.11b network with G.711 voice codec is about 85 simultaneous calls, but the actual observed capacity is only 5 calls even at the highest data rate and under zero loss conditions. In this paper we analyze the reasons behind this inferior performance of VoIP traffic. We also present algorithms at the medium access control layer to improve the observed call capacity. Using ns-2 based simulations, we evaluate the algorithms and show that performance improvements of more than 300% can be achieved. Finally, using a testbed implementation of one of the proposed algorithms, we show its feasibilty in real world VoIP implementations.


VoIP Wi-Fi networks call capacity ACK aggregation frame aggregation link adaptation 


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Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  • Yeonsik Jeong
    • 1
    Email author
  • Sandeep Kakumanu
    • 2
  • Cheng-Lin Tsao
    • 2
  • Raghupathy Sivakumar
    • 2
  1. 1.Department of Multimedia System EngineeringSungKongHoe UniversitySeoulKorea
  2. 2.School of Electrical and Computer EngineeringGeorgia Institute of TechnologyAtlantaUSA

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