Re: What does 95th %tile mean?

[Sean Donelan <sean () donelan com>]

On Thu, 19 April 2001, Geoff Huston wrote:
> 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_?

The great thing about changing jobs every once in a while is I get to
experience the joy of looking at things from the outside.  Because colo's
use a lot of power, I'm learning a lot about how the electric companies
work.  Geez, if you thought telephone companies were bad :-)

The power industry has a version of the 95% billing.  Like ISPs, originally
it was a simple measurement every 5 (10, 15, etc) minutes.  Figure out
the peak measurement, and you are done.  Users figured out how to better
control their usage, i.e. turning on motors for 9 minutes and then turning
them off for six minutes.

Were there billing disputes, you betcha!

Now electric companies use a variety of sliding windows, and different ways
to calculate usage.  The top-of-the-line power meters have over 100 different
ways to measure (and therefor different ways a utility can charge) power
consumption. Each becoming progressively more complex, trying to eliminate
ways for people to game the system. To resolve some billing disputes, the
top meters include "pulse" connections so you can precisely synchronize
your check meter with the utility's meter for auditing.

So, does someone need to develop an Internet meter for your Internet line
with a dial which spins faster when you use more packets?