RE: What does 95th %tile mean?

[RJ Atkinson <rja () inet org>]

        I've seen both "in or out" and "in + out" used
by multiple providers within the community.  So either
approach could be called "industry standard method".

        As Lee notes, one ought to define the precise
algorithm as part of the contract, to avoid just this
sort of ambiguity.

Ran

At 10:18 19/04/01, Lee Watterworth wrote:
> ...definately one of those things that need to be asked about during
> contract negotiations...
>
> -----Original Message-----
> From: Alex Rubenstein [mailto:alex () corp nac net]
> Sent: April 19, 2001 10:09 AM
> To: 'nanog () merit edu'
> Subject: What does 95th %tile mean?
>
>
>
> I've gotten myself into an argument with a provider about the definition of
> 'industry-standard 95th percentile method.'
>
> To me, this means the following:
>
> a) take the number of bytes xfered over a 5 minute period, and determine
> rate for both the inbound and outbound. Store this in your favorite
> data-store.
>
> b) at billing time, presumably on the first of the month or some other
> monthly increment, take all the samples, sort them from greatest to least,
> hacking off the top 5% of samples. Actually, this is done twice, once for
> inbound, once for outbound. Then, take the higher of those two, and multiply
> it by your favorite $ multiple (ie, $500 per megabit per second, or $1 per
> kilobit per second, etc).
>
> I think that most people agree with the above; the issue we are running into
> is one rogue provider who is billing this at in + out, not the greater of in
> or out.
>
> How is everyone else doing it? Specifically, larger folks (UU, Sprint, CW,
> Exodus/FGC, GX, Qwest, L3)
>
> Thanks!