An Analytical Model for Capacity Evaluation of VoIP on HCCA and TCP File Transfers over EDCA in an IEEE 802.11e WLAN

  • Sri Harsha
  • S. V. R. Anand
  • Anurag Kumar
  • Vinod Sharma
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4308)


In the context of the IEEE 802.11e standard for WLANs, we provide an analytical model for obtaining the maximum number of VoIP calls that can be supported on HCCA, such that the delay QoS constraint of the accepted calls is met, when TCP downloads are coexistent on EDCA. In this scenario, we derive the TCP download throughput by using an analytical model for the case where only TCP sessions are present in the WLAN. We show that the analytical model for combined voice and TCP transfers provides accurate results in comparison with simulations (using ns-2).


Medium Access Control Voice Call Contention Period Service Interval Voice Packet 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Sri Harsha
    • 1
  • S. V. R. Anand
    • 1
  • Anurag Kumar
    • 1
  • Vinod Sharma
    • 1
  1. 1.Department of Electrical Communication EngineeringIndian Institute of ScienceBangalore

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