SMART Letter #41
THE MYTH OF FIVE NINES
June 23, 2000
SMART Letter #41 -- June 23, 2000
Copyright 2000 by David S. Isenberg
isen.com -- "reliable information on flaky media"
email@example.com -- http://isen.com/ -- 1-888-isen-com
> The Myth of Five Nines
> Copper Corrupts
> Wireless is Worse
> TeraBeam isn't Terrible without Five Nines
> Conferences on my Calendar, Copyright Notice, Administrivia
THE MYTH OF FIVE NINES
by David S. Isenberg
The telephone companies brag about "five nines." They'd like
you to believe that their networks function 99.999% of the
time. That means they'll be down a mere 5.256 minutes a year.
(Check my arithmetic, please. I've been known to slip a
The phone companies use such bragging to spread Fear,
Uncertainty and Doubt (FUD) about other communications
technologies. "If you're having a heart attack, you're not
going to depend on the Internet," the Bell-heads assert. "If
the power goes out, you're not going to be able to notify the
Power Company from your PC," they allege.
Last week I got back from a four-day road trip at 10:00 PM to
find that my dial-up phone line, the one I use for email,
etc., didn't have a dial tone. So I called Bell Atlantic.
They promised to send somebody out the next day between noon
and 6:00 PM.
By my calculations -- not guaranteed to much precision at all,
but directionally correct -- if Bell Atlantic had fixed my
line on the dot of noon, they'd owe me about four thousand,
four hundred and fifteen years of 99.999% up-time. And if
they took until 6:00 PM to fix it, they'd owe me another one
thousand, eight hundred and ninety-two years, give or take a
I think that telco technicians -- the guys (mostly) who wear
hard hats and climb poles -- know more about telephone
networks than most of us at Bell Labs ever did. Vinnie, who
came to fix my phone line, arrived about 2:00 PM. He
certainly knew a lot. He tested my line at the demarc on the
side of my house, and then he went up the nearest pole in the
cherry picker on top of his truck. Yup, he said, the problem
was on the Bell Atlantic side.
Then Vinnie said he needed to check the box on Grove Street,
and he drove away. Half an hour later he came back. He said
that a previous repairman had dropped a clipping of copper
wire onto that end of my twisted pair. This had shortened my
circuit by about two-thirds of a mile.
He figured he'd fixed it, so we plugged in the most vanilla
2500 set I had in the closet, where I keep it just in case the
electricity goes out while I'm having a heart attack, and went
off-hook. I listened. The noise on the line sounded just
like my little red AM radio used to sound when the Yankees
game was suspended due to thunderstorms.
Vinnie listened too. "That's not right," he said. "I'll be
right back." He drove off in his truck. Half an hour later
he came back. "The cable up on Tamaques was full of water. I
drained it," he reported. "Try it now."
I listened. The line sounded just like the one AM station I
could get on the crystal set I built for my Cub Scout Weblos
badge. "That's still not right," Vinnie said.
He went up the pole outside my house again. "Try it now," he
yelled through my open window. I tried it. It was clean.
Vinnie called me on his fanny phone. It sounded great. "I
replaced the screws and washers up here," he said. High tech.
In 1995, during the ITV fad, Ray Smith, the last RBOC CEO with
a personality, said that fiber in the local loop would pay for
itself on truck-rolls alone. That must be why my house in the
Bell Labs ghetto, half way between Bell Labs Murray Hill and
Bell Labs Holmdel, still uses copper loops.
In fairness to Bell Atlantic, I have three lines, and I've
only had one service call in the last year. So I'm happy to
give them the benefit of the doubt -- they only owe me one
thousand nine hundred and forty-four years of up-time.
Furthermore, maybe my experience isn't typical . . .
WIRELESS IS WORSE
No wireless mobile network I've used has a 'nine' to call its
own. I have a problem with approximately one call out of
every two -- so it rates 'one five', or 50%. Sometimes the
call doesn't complete. Other times the signal fades or
becomes incomprehensible. ("What? Yes, honey, I love you,
too. I said I love you. What? I can't hear you. Yes, love
you. Goodbye.") Or the call ends before I'm done. (I hate
it when I've been on hold for seven minutes and the
Continental ticket agent finally answers and I hear, "Thank
you for calling Continental. How may I hel . . . *click*.")
Often, an incoming call can't find enough spectrum where my
phone is, so the call is diverted to voice mail, and I am
alerted hours later -- "reap, reap, reap," I've got mail.
Nevertheless, I keep (and even love) my cell phone.
The so-called Wireless Web is a different animal entirely than
the one I tamed in 1996 with my QWERTY keyboard, my mouse and
my fifteen-inch screen. The medium, let us not forget, is the
I just shut off my Wireless Web service. The reason was spam
-- junk email sent by entrepreneurially-challenged people who
used to be happy watching late-night TV teach them how to
place little classified ads in newspapers. Spam isn't
annoying at all on a standard, wired terminal. I actually like
to search and destroy messages entitled "Earn $10,000 At Home",
"Talk to Hot Babes", and "Raise Gerbils for Fun and Profit".
I hold down the Cntl key and select each one. Then, with one
avenging touch of the Delete key, I blow 'em all straight to
the recycle bin.
But then spamsters found my Sprint PCS email. Wireless spam
is hard to delete. It is a waste of time, attention, and
money. So I told Sprint to turn off my email. Now I'm stuck
with an almost-new $300 Sprint Motorola Timeport web-enabled
but disabled cell phone.
It all started with my post-Japan-visit desire to experience
the joys of DoCoMony on the Wireless Web. I signed up for
Sprint's short message service. It costs $9.99 for thirty
(30) messages a month. Messages can be up to 100 characters
long. That's thirty-three cents a message. Or, at 14,400
bits per second, it's $4.75 a minute, assuming 100 characters.
Talk about premium pricing!
To send me a message, you had to send it to
That's harder to remember than firstname.lastname@example.org. But one of the
cool things about email is that the user is in control, or so
I thought. So I set
email@example.com as an alias -- it is
easier to remember than
I put it on my web site so SMART People who didn't want to
talk to me in real time could remember my address if they
wanted to send me a message. And that's where the spamsters'
reaper harvested it.
Then, a couple of times a day my phone would "reap-reap-reap".
I'd push the 'Envelope' button, cursor down three lines to
"messages", push the 'Select' button on the side of the phone
to see that message 1 was from "firstname.lastname@example.org". Then I'd
select the message to read: "Hi! Are you tired of working for
the same old b . . . " Then I'd push the 'Clr' button to
delete the message and push one more button to confirm the
deletion . . . then I'd run the red light narrowly avoiding
the father with the baby carriage, only to drift off the
shoulder and over the guard rail. Wireless email certainly is
Before the wireless web, I was spam-agnostic. Now I hate it
with a militant passion. An email sender who uses a nobody-
home return address should be held in stocks on the village
green for two weeks. And DUIE (driving under the influence of
email) should be punishable by dunking -- I'm guilty as
Furthermore, we need wireless services that aren't priced
according to some Bell-headed paradigm designed to keep us
from using them. And we need user interfaces that aren't
designed as an afterthought by electrical engineers.
But I love my cell phone, even if it doesn't have a nine to
its name. Furthermore, I believe that there are other
wireless mobile devices that make it easier to delete spam.
And someday there will be pricing plans that don't penalize
me for other people's inconsideration.
I also believe that the Internet Protocol will tame the
unreliable mobile wireless physical layer, to replace
unreliable voice services with pretty good email.
TERABEAM ISN'T TERRIBLE WITHOUT FIVE 'NINES'
Readers of previous SMART Letters know that I have a stake in
TeraBeam, the Seattle-based laser communications company
that's causing WinStar's and Teligent's stock to tank. Well,
I do, and I'm proud of it.
And I am proud to say that TeraBeam's management doesn't claim
that lasercom is a five 'nines' technology.
There's some weather that I shouldn't drive in. There's some
weather that make me glad that my airplane is staying on the
ground, no matter how bad I 'need' to be there. And there are
some weather conditions (e.g., dense fog) that will not get a
laser-borne gigabit very far through the air.
Would I like to have a gigabit with two, three or four 'nines'
or no gigabit? I'll take the gigabit, thank you; hold the
In the age of internetworking, I can roll my own reliability.
As long as there's a healthy market with multiple competitors
(repeat, multiple competitors), bandwidth is bandwidth is
bandwidth. If I buy three services on three different
physical layers from three different service providers, and if
each service is two 'nines', then I should have a six 'nines'
probability that one service will always be up. It will cost
three times more, but at least I'll be getting what I'm paying
CONFERENCES ON MY CALENDAR
June 26-27, 2000. New York City. Entertainment Internet
2000. I'll be on a panel with some of my favorite fiber and
bandwidth companies. The website is thin, but there's info
there -- http://www.imn.org/2000/a245 or call 212-336-6000.
September 13-15, 2000. Lake Tahoe CA. TELECOSM. Featuring
George Gilder, Clayton Christensen, yours truly, and a cast of
geniuses, troublemakers, and people who got rich by listening
to George. This thing sells out, folks -- a word to the SMART.
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Copyright 2000 by David S. Isenberg
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