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North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: What does 95th %tile mean?
The 95% reading always struck me as a randomly generated number in any case. Take an extreme example - a customer operates a wire such that both in and out are at line rate for five minutes, and then both in and out are idle for five minutes, continually. Depending on the synchronization between the burst pattern and the sampling system, and the sampling technique itself, the 95% reading can be zero, half the line rate, or the line rate, and all answers are equally valid in some sense. While real situations do not exhibit such a large range of potential variability (i.e. 100%), there is still a hefty level of variation in a 95% reading due to the interactions between the time base of the traffic, the time base of the meter engine and the sampling technique used by the meter engine. It leads to the situation where the provider confidently asserts that the 95% value was xkbps, and the customer confidently asserting ykbps and both readings are equally valid, with both measurements using the _same_ measurement technique. How is the consequent billing dispute resolved _fairly_?
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