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Inventing the Internet Again
Unique to
his vision was its grasp of the economics of a network that could handle
“the expected exponential growth in the transmission of digital data.”
Declaring that “it would be possible to build extremely reliable
communications networks out of low-cost unreliable links, even links so
unreliable as to be unusable in present-type networks,” he estimated
that the price of the system would be some $60 million per year. That
was some 20 to 30 times less than what was being paid by the Department
of Defense for their leased communications systems without any of these
features. It was two orders of magnitude cheaper than new analog national
systems being proposed at the time by each of the three military services.
Thus Baran not only conceived the essential technical features of the
Internet, he also prophesied the cliff of costs over which digital technology
would take the networking industry. By imagining the compounding effects
of Moore’s law three years before Moore’s own famous prophecy,
Baran stressed the key economic drivers that impelled the prevalence of
the Web as the universal Net.
The system of communications that Baran attacked in the early 1960s at
RAND was the imperial establishment of AT&T. As Baran explains, “While
AT&T did have digital transmission under examination, it was in the
context of fitting directly into the plant by replacing existing units
on a one-for-one basis. A digital repeater unit would replace an analog
loading coil. A digital multiplexer would replace an analog channel bank-always
a one-for-one conceptual replacement, never a drastic change of basic
architecture. I think that AT&T’s views on digital networks were
most honestly summarized by AT&T’s Joern Ostermann after an exasperating
session with me: ‘First, it can’t possibly work, and if it did,
damned if we are going to allow the creation of a competitor to ourselves.’“
In 1972 the company sealed its fate by turning down an opportunity to
buy the entire Arpanet. As Larry Roberts explained in Where Wizards Stay
Up Late, “They finally concluded that the packet technology was incompatible
with the AT&T network.” So it was and so it still is. The existing
phone system remains the chief obstacle to the final triumph of the Net.
But the logic of digital communications is inexorable. It will displace
all the existing establishments of television and telephony.
Wasted Forever... Like Water Over a Dam
These days Baran’s vision, however, goes far beyond wireline communications.
Baran takes the Internet model and extends it boldly to wireless communications.
On June 23, 1995, on the occasion of the Marconi Centennial, marking the
100th anniversary of the invention of the radio, Baran gave a momentous
keynote speech in Bologna, Italy. In it he demanded a radical reconception
of wireless networks.
“The first 100 years of radio,” he declared, were marked by
a perpetual “scarcity of spectrum.... One of the very first questions
asked of young Marconi about his nascent technology was whether it would
ever be possible to operate more than one transmitter at a time. Marconi’s
key British patent #7,777 taught the use of resonant tuning to permit
multiple transmitters.... [Yet] even today, with over 30,000 times more
spectrum at our disposal than in Marconi’s day, entrepreneurs wishing
to implement new services encounter the same perpetual shortage of frequencies.”
Focusing on the most desired bands between 300 and 3,000 megahertz (UHF),
Baran asserted that when you “tune a spectrum analyzer across a band
of UHF frequencies,:” you discover that “much of the radio band
is empty much of the time. This unused spectrum might be available for
transmission if we could take measurements and know exactly when and where
to send the signal.”
As an example, he cited “the many millions of cordless telephones,
burglar alarms, wireless house controllers, and other appliances now operating
within a minuscule portion of the spectrum and with limited interference
to one another. These early units are very low power dumb devices compared
to equipment being developed that can change its frequencies and minimize
radiated power to better avoid interference to itself and to others.
“In part,” he declared, “the frequency shortage is caused
by thinking solely in terms of dumb transmitters and dumb receivers. With
today’s smart electronics, even occupied frequencies could potentially
be used.”
The chief reason for the apparent shortage of spectrum, he concluded,
is regulation of it. Echoing his earlier critique of wireline communications,
he declared that “the present regulatory mentality tends to think
in terms of a centralized control structure, altogether too reminiscent
of the old Soviet economy. As we know today, that particular form of centralized
system... ultimately broke down. Emphasis with that structure was on limiting
distribution rather than on maximizing the creation of goods and services.
Some say that this old highly centralized model of economic control remains
alive and well today-not in Moscow but within our own radio regulatory
agencies.”
The heart of the problem is the concept of spectrum as public property-as
scarce real estate or a precious natural resource. Spectrum is nothing
of the kind. It has been created by a series of brilliant technical innovations,
beginning with Marconi and continuing in a steady stream of high technology
oscillators and digital signal processors: from magnetrons and kystrons
to varactor multipliers and surface acoustical wave devices, from gallium
arsenide and indium phosphide heterojunctions to voltage-controlled oscillators
and Gunn or IMPATT diodes. Spectrum is chiefly a product of inventors
and entrepreneurs. Americans will rue the day when foreign governments
and international organizations begin auctioning and taxing, marshaling
and mandating the use of these mostly American technologies.
The real estate model applies chiefly to broadcasters and others using
analog modulation schemes in which all interference shows up in the signal.
A television signal requires some 50 decibels of signal to noise power,
or 100,000-to-1. By contrast, error-corrected digital signals can offer
virtually perfect communications at a signal-to- noise ratio well below
10 decibels, or 10,000 times less. Moreover, new digital systems can divide
and subdivide the spectrum space into cells and differentiate calls by
spread- spectrum codes or even isolate particular connections in space
by space-division-multiple-access-devices that function as “virtual
wires” allocating all of the spectrum to each call.
Baran pointed out that “any transmission capacity not used is wasted
forever, like water over the dam. And there has been water pouring here
for many, many years, even during an endless spectrum drought.:”
Although Baran urged as an ideal the transfer of the 480 megahertz of
spectrum currently occupied by analog broadcasters to fiber optics and
cable coax, he said, “We don’t have to wait [for this ideal
solution]....The existing spectrum can be more efficiently used by resorting
to smart receivers and transmitters.”
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