North American Network Operators Group

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RE: The Myth of Five 9's Reliability (fwd)

  • From: Bruce Williams
  • Date: Wed Apr 24 20:35:18 2002


> -----Original Message-----
> From: [email protected] [mailto:[email protected]]On Behalf Of
> Art Houle
> Sent: Wednesday, April 24, 2002 1:52 PM
> To: Pete Kruckenberg
> Cc: [email protected]
> Subject: Re: The Myth of Five 9's Reliability (fwd)
>
>
>
>
> How to calculate uptime and get 5 9s
>
> -do not include any outage less than 20 minutes.
> -only include down lines that are actually reported by customers.
> -when possible fix the line and report 'no trouble found'.
>

These can all accomplished with one simple and elegant system policy rule.
It also has the advantage of "tuneability". If you hold off determining if
there is an interruption of service for X minutes, then NO interruptions of
service shorter than X minutes exist, since the service is functional when
tested. Also, a call center that first "routes"  tickets to the "appropriate
area"  can deliver 99.99 with little effort. ( in fact, the LESS
effort/clue, the BETTER the rating ! )

BTW - One of my best friends growing up ( and we took EE together )
grandfather was the V.P. in charge of AT&T's LongLines division while a lot
of the "wire was pulled". From what he said of his grandfather's remarks,
they didn't think about five 9's. The question was how much spare/redundant
capacity did you have, both for dependability and to support the countries
growth. Not exactly "this quarter's profit" thinking -sigh-.

Bruce Williams
"Two is not equal to three, even for large values of two"