North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: 95th Percentile again!
On Sun, 3 Jun 2001, Greg A. Woods wrote: > [ 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). Actually I was refering to the more common methods of rate based measurement, MRTG. The names of the providers who use this will be omitted. :P -- Richard A Steenbergen <[email protected]> http://www.e-gerbil.net/ras PGP Key ID: 0x138EA177 (67 29 D7 BC E8 18 3E DA B2 46 B3 D8 14 36 FE B6)
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