Re: 95th Percentile again (was RE: C&W Peering Problem?)

["Richard A. Steenbergen" <ras () e-gerbil net>]

On Sun, 3 Jun 2001, Joe Abley wrote:

> > I think your argument is in favor of 95th percentile vs an accurate
> > average, not rate vs amount samples. If for some reason you lose a sample
> > with an average system, your revenue goes down, whereas if you lose a
> > sample in 95th percentile you're more likely not to make it go down much.
>
> Not really. For any averaging function you care to apply to the sample
> population, there will be some samples that tend to increase the
> result, and some that tend to decrease the result. Whether or not the
> billable value goes up or down depends on the sample that was dropped,
> on the remaining samples, and on the averaging function being used.

No, you're working under the assumption that the divisor goes up only with
increased samples, while the system I outlined continues to go up with the
progression of time. No reason that can't be changed though, and that
isn't important to the argument... :P

> > I'd say the real problem is with the vendor. Fortunantly most people have
> > counters.
>
> Suppose you are selling transit to several customers across a switch
> operated by someone else (an exchange operator, for example), such
> that the traffic for several customers is carried by a single
> interface on your router. Suppose direct interconnects are not
> practical, and suppose you have no access to any counters that may be
> available on the switch.
>
> The options are: (1) do not sell to these customers, or (2) find some
> way to sell to these customers by counting packets yourself. Option
> (1) presents a far more consistent opportunity to decrease potential
> revenue than does option (2).

You can do it with VLANs, I believe Equinix does this on their exchange
switches.

-- 
Richard A Steenbergen <ras () e-gerbil net>       http://www.e-gerbil.net/ras
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