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Re: Another Point Of View (Round 2)
Mike Bilow wrote:
>I have considerably more mathematical education than "an elementary course,"
>and I have no idea what you are talking about. What you seem to be describing
>here is the behavior of the classic Poisson distribution, which is (as far
>know) the accepted mathematical model for this sort of traffic analysis.
Voice traffic follows a classic exponential, or Poission, distribution. It
is the basis for the Erlang tables used by phone companies to provision
trunk groups. Data calls *Do Not* follow a Poisson distribution. See
"Impacts of Internet Traffic on LEC Networks and Switching Sysetms", Amir
Atai and James Gordon. (Note that nomenclature for Probability Density
Functions is not uniform. Perhaps you learned about Power Law PDFs under a
different name. Or maybe you were absent that day :)
> BF> Ignoring the fundamentals of traffic engineering, CPT argues
> BF> that a 20-minute local data call costs the phone company the
> BF> same as a 20-minute teenage yak-fest,
>This isn't true?
Of course a 20-minute call is a 20-minute call regardless of whether it's
voice or data. But that's not the point. The phone network is not
engineered to handle 20-minute average holding time calls. In addition,
it's not the *average* call that matters, it's the total call-minute load
presented by the entire distribution function.
> BF> I tried explaining this to the dunderhead social engineers
> BF> that populate CPT's ISDN mailing list some months ago,
>I object to that "social" allegation.
OK. Next time I'll call you anti-social :)