[comp.dcom.telecom] Expensive Telephone Plant???

0004133373@mcimail.com (Donald E. Kimberlin) (07/28/90)

It seems many readers continue to support the archaic notion that the
costs of capital investment drive the telephone business ... a
principle that was established in 1913.  It's a principle that still
prevails for utility companies that have had little real technology
change.  It takes heavy pipe and large tanks to deliver water or gas;
it takes heavy copper wire and massive generators (even with nuclear
power) to deliver increasing amounts of electricity.  But, the
semiconductor revolution coupled with the age of computers has so
changed the nature of "the phone business" that capital needs are now
trivial compared to even a decade ago.

        The "phone industry's" nature has changed, but it continues to
parade behind the mask of its 1913 face, aided and abetted by state
regulators and a public that simultaneously is enjoying its romance
with the phone <Time for a movie called "Romancing the Phone"?> and
fears its power as well as that of its suppliers.

        Come to think of it, I seem to recall that's the sociologists'
definition of a religion ... respecting an entity that combines loving
grace and fear in one; an entity of incomprehensible makeup and
structure.  Isn't that how most people see "the phone"?

        Here's an attempt to make it clear to those who refuse to
understand just how much the capital needs of telecommunications have
plunged and will continue to fall. For those who do not understand the
technology, suffice it to say that today, the fiber optics
communications systems in place and being installed are in a similar
development state to where radio was in 1912.  We have yet to deploy
controlled, controllable lightwave generators that produce pure,
stable bearer signals for our information.  In a lightwave sense, we
are blasting away at the fiber as "Sparks" did with his
Frankenstein-like machine in the radio shack aboard the Lusitania.
Once we do get stable, pure transmitters in use, we will be able to
multiply use of the spectrum in every fiber by exponential amounts.

The following (edited) news story is from {Communications News} for
July, 1990:

             "CAN A SINGLE FIBER CARRY 56 MILLION CALLS?

        "British scientists say they have proved the ability of a
single fiberoptic telephone line to carry 56 million simultaneous
telephone calls.

        "Testing a new coherent" <and that's the key physics term,
readers, just as "coherent waves" were in 1912!> "optical system,
researchers transmitted two wavelengths over that same fiber for 75
miles with an optical repeater" <get this ... "optical repeater" means
"analog amplifier!"> "43 miles from the transmitter.

        "Each of the two" <lightwave channels on one fiber> "carried
622 megabits per second, equal to about 8,000 telephone lines per
channel.

        "The British Telecom scientists found that separation of the
two wavelengths could be reduced to as little as 7 Ghz before they
began to interfere with each other."  <For the uninitiated, the
frequency of the 1300 nanometer light used by most common carriers is
about 230 million megahertz and 7 gigahertz is 7 thousand megahertz.>
But with" <a bandwidth of about> "50,000 Gigahertz" <available> "on
one fiber, each fiber could in theory carry 7,000" ... "channels with
8,000 calls on each -- 56 million calls.

        "In practice, the researchers concede, it is more difficult."
<It was pretty tough in 1912, too!> "The power spectrum of the fiber
and the power budget, the difference between the maximum power optical
devices can provide and the noise floor, are shared among the many
wavelengths used.

        "Still, the scientists say, it is clear that it will be
possible to transmit a vast number of wavelengths on one fiber.

        "Coherent optical systems along with optical amplifiers"
<a.k.a. ANALOG, dear Reader!>" make it possible to transmit calls and
data over long distances.  With the number of wavelengths possible, it
should be possible to route through the telephone network and avoid
the need for electronic switches, whose limited capacity can cause
bottlenecks."

        Pause for My editorial commment: So now we see not only less
need to keep plowing in more fiber cable just for capacity, but also a
reduced need for switching machines, eh?  Just HOW much new capital
investment do you really need, Mr. Telephone Company? Now, back to our
story:

        "Coherent transmission makes electronic regenerators
unnecessary because very low noise amplification and distortion- free
pulse transmission techniques are involved."

        Pause again: But haven't we all been proseletyzed for two
decades that digital transmission with regenerators got rid of all the
noise of those nasty, fussy analog methods?  It seems now that we are
in a different part of the electromagnetic spectrum with a nice
enclosed, impervious transmission pipeline that analog is back again.
But the story continues:

        "The scientists are also working on another transmission
system that shows promise of handling more phoen calls on a single
channel.

        "Demonstrating a non-linear" <now we're talking digital again>
"high-capacity transmission system, they simulated a 20 gigabit per
second data rate over a 62-mile fiber span in non-laboratory
conditions.  This is equivalent to 300,000 phone calls.

        "Current linear" <read analog> "systems transmit the
equivalent of 4000 calls over 18 miles, while the next generation
should handle 30,000 calls over 30 miles.

        "Linear systems are expected to ultimately transmit up to
150,000 phone calls over a distance of 60 miles...

        "Beyond that, improvements in performance are unlikely because
of a phenomenon that blurs the edges off transmitted data pulses" ...
"and makes received data unintelligible."

         Well, all that the last sentence said was that we have
identified the limit of pulse length at which the smallest element
gets so small it gets mixed up with the medium.  We've been around
that loop in telecomm history several times.  But, look how far below
that limit we are today, and how much additional capacity can be wrung
from glass strands that are far cheaper than equivalent copper
capacity!

         What with the prospects for being able to increase its
capacity manifold without buying more real estate, buildings and heavy
machinery, "the phone company" is clearly no longer in the capital-
intensive business "the phone" was 80 years ago when we set the
current rate policy track.

         This being a forum full of educators, there should be plenty
of fodder in such news for graduate work.  And, the public needs to
know ... somehow... that "the phone" is no longer pounds of copper on
a pole and the plain black subset on the stand in Aunt Sally's
hallway!  Power, water, gas and sewer utilities may still be trapped
in heavy,expensive technologies by the very nature of their product,
but "the phone company" is freed of all that ... whenever it chooses
to take up the freedom.  The focus of our attention and wrath, if need
be, ought to be the state regulators ... in every state.


[Moderator's Note: Thank you for an excellent message today.  PT]