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Article:
  How Many Voice Callers Fit on the Head of an Access Point?
Subject:   wrong question -> irrelevant numbers
Date:   2005-12-16 01:14:01
From:   fireless
Quite a disappointing article adding to common misconceptions about 802.11. Calculations are technically correct, but are giving answer to a wrong questions.
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  • Ted Wallingford photo wrong question -> irrelevant numbers
    2006-01-20 12:21:17  Ted Wallingford | O'Reilly Author [View]

    WHAT? Try again, Fireless. This is probably one of the soundest analysis I've seen. The only thing it doesn't really take into account is poor radio performance, which is entirely peripheral anyway.
    • wrong question -> irrelevant numbers
      2006-11-13 15:55:07  MaxDowney [View]

      Nah, the analysis doesn't take into account the delay inherent in 802.11b's Distributed Coordination Function.

      Back of the envelope calculations would show that using G.711 A-Law encoded audio transmitted in 20 ms blocks (say 160bytes of audio per frame) at 11Mbps would give a maximum of 12 VoIP calls possible and this still doesn't take into account a noisy channel which increases the amount of time wasted in the DCF.

      Max