95th Percentile again!

Sun Jun 3 04:56:06 UTC 2001

[ On Saturday, June 2, 2001 at 23:17:48 (-0400), Richard A. Steenbergen wrote: ]
> Subject: Re: 95th Percentile again (was RE: C&W Peering Problem?)
>
> No matter how you stack it, if you miss a rate sample there is no way to
> go back and get the data again. You either discard it and lose the ability
> to bill the customer for it (which demands high availability polling
> systems), or you make up a number and hope the customer doesn't notice.
> Volume polling does not suffer from this problem.

What the heck are you talking about?  Only a totally amateur design
would fail to account for the possibility of a dropped sample (or any
other of several critical issues faced by anyone using counters to
determine the average or Nth percentile rates).

In fact the accounting for bulk throughput per period is done in almost
exactly the same as any rate-based accounting too (only the counter
sample time might differ, but of course you can't stretch it too far for
the former case lest you risk an undetectable wrap-around event).

-- 
							Greg A. Woods

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