FIBER KEEPS ITS PROMISE
BY
GEORGE GILDER
"Today, I await the death of television, telephony, VCRs,
and analog cameras with utter confidence as Moore’s law
unfolds." Rupert Murdoch, Ted Turner, John Malone, are
you listening?"
Get ready. Bandwidth will triple each year for
the next 25, creating trillions in new wealth.
Editor’s note: Four years ago, Forbes ASAP published its first issue with
a stunning prophecy by contributing editor George Gilder. Fiber optics,
said George, had the potential to carry 25 trillion bits per second down
a single strand. This represented a ten-thousandfold leap in carrying
capacity over the 2.5 billion bits "barrier" long assumed by most experts
in the field. What did George see that others had missed? One, a
little-recognized (at the time) breakthrough called an erbium-doped
amplifier, which keeps optical signals pure and strong over long distances.
The other was a deep technical shift, with roots in the 1940s-era work of
information theory pioneer Claude Shannon. If you believed Shannon, his
logic dictated a new messaging scheme called wave division multiplexing.
Though scorned by the experts four years ago, WDM now is emerging as the
winner George had prophesied.
The real winners will be all of us, as the coming world of cheap,
unlimited bandwidth unfolds and at last fulfills the true potential
of the information age. Here is George with an update.
IMAGINE THAT IN 1975 YOU KNEW that Moore’s law–the Intel chairman’s
projection of the doubling of the number of transistors on a microchip
every 18 months–would hold for the rest of your lifetime. What if you
knew that these transistors would run cooler, faster, better, and cheaper
as they got smaller and were crammed more closely together? Suppose you
knew the law of the microcosm: that the cost-effectiveness of any
number of "n" transistors on a single silicon sliver would rise by the
square of the increase in "n."
As an investor knowing this Moore’s law trajectory, you would have
been able to predict and exploit a long series of developments: the
emergence of the PC; its dominance over all other computer form factors;
the success of companies making chips, disk drives, peripherals, and
software for this machine. With a slight effort of intellect, you
could have extended the insight and prophesied the digitization of
watches, records (CDs), cellular phones, cameras, TVs, broadcast
satellites, and other devices that can use miniaturized computer power.
If you did not know precisely when each of these benisons would flourish,
you would have known that each one was essentially inevitable. To
calculate approximate dates, you had only to guess the product’s optimal
price of popularization and then match its need for mips (millions of
instructions per second) of computer power with the cost of those mips
as defined by Moore’s law.
Merely by using this technique of Moore’s law matching–and holding
to it with unshakable conviction for nearly 20 years–I became known as
a "futurist." Today I await the death of television, telephony, VCRs,
and analog cameras with utter confidence as Moore’s law unfolds. You
can tell me about the 98% penetration of TVs in American homes, the
continuing popularity of couch-potato entertainments, the effectiveness
of broadcast advertising, and the profound and unbridgeable chasm
between the office appliance and the living-room tube. But I will pay
no attention. Just you wait–Jack Welch, Ted Turner, Rupert Murdoch,
John Malone, and David Jennings–the TV will die and you may be too late
for the Net.
It is now 1997, and a stream of dramatic events certifies that
another law, as powerful and fateful and inexorable as Moore’s, is
gaining a similar sway over the future of technology. It is what I have
termed the law of the telecosm.
Its physical base lies in the same quantum realm of eigenstates
and band gaps that governs the performance of transistors and also makes
photons leap and lase. But the telecosm reaches beyond components to
systems, combining the science of the electromagnetic spectrum with Claude
Shannon’s information theory. In essence, as frequencies rise and
wavelengths drop, digital performance improves exponentially. Bandwidth
rises, power usage sinks, antenna size shrinks, interference collapses,
error rates plummet.
The law of the telecosm ordains that the total bandwidth of
communications systems will triple every year for the next 25 years. As
communicators move up-spectrum, they can use bandwidth as a substitute
for power, memory, and switching. This results in far cheaper and more
efficient systems. In 1996, the new fiber paradigm emerged in full force.
Parallel communications in all-optical networks became the dominant source
of new bandwidth in telecom. Like Moore’s law, the law of the telecosm
will reshape the entire world of information technology. It defines the
direction of technological advance, the vectors of growth, the sweet spots
for finance.
AMERICA’S DARK SECRET
FOR MORE THAN A DECADE, American companies have been laying optical
fiber strands at a pace of some 4,000 miles a day, for a total of more
than 25 million strand miles. Five years ago, the top 10% of U.S. homes
and businesses were, on average, a thousand households away from a fiber
node; now they are a hundred households away.
However, the imperial advance of this technology conceals a dark
secret, which has led to a pervasive underestimation of the long-term
impact of photonics. Sixty percent of the fiber remains "dark" (unused
for communications) and even the leading-edge "lit" fiber is being used
at less than one ten-thousandth of its intrinsic capacity. This problem
has prompted leaders in the industry, from Bill Gates and Andy Grove to
Bob Metcalfe and Mitch Kapor, to underrate drastically the impact of fiber
optics.
Restricting the speed and cost-effectiveness of fiber has been an
electronic bottleneck and a regulatory noose. In order for the signal
to be amplified, regenerated, or switched, the light pulses had to be
transformed into electronic pulses by optoelectronic converters. For
all the talk of the speed of light, fiber-optic systems therefore could
pass bits no faster than the switching speed of transistors, which tops
out at a cycle time of between 2.5 and 10 gigahertz. Meanwhile, telecom
companies could not deploy new low-cost fiber products any faster than
the switching speed of politicians and regulators, which tops out roughly
at a cycle time of between 2.5 years and a rate of evolution measurable
only by means of carbon 14.
Nonetheless, the intrinsic capacity of every fiber line is not 2.5
gigahertz. Nor is it even 25 gigahertz, which is roughly the capacity
of all the frequencies commonly used in the air, from AM radio to kA
band satellite. The intrinsic capacity of every fiber thread, as thin
as a human hair, is at the least one thousand times the capacity of what
we call the "air." One thread could carry all the calls in America on
the peak moment of Mother’s Day. One fiber thread could carry 25 times
more bits than last year’s average traffic load of all the world’s
communications networks put together: an estimated terabit (trillion
bits) a second.
Over the last five years, technological breakthroughs and
legislative loopholes have begun to open up this immense capacity to
possible use. Following concepts pioneered and patented by David Payne
at the University of Southampton in England, a Bell Laboratories group
led by Emmanuel Desurvire and Randy Giles developed a workable
all-optical device. They showed that a short stretch of fiber doped
with erbium, a rare earth mineral, and excited by a cheap laser diode
can function as a powerful amplifier over fully 4,500 gigahertz of the
25,000 gigahertz span. Introduced by Pirelli of Italy and popularized
by Ciena Corporation of Savage, Maryland, and by Lucent and Alcatel,
today such photonic amplifiers are a practical reality. Put in packages
between two and three cubic inches in size, the erbium-doped fiber
amplifiers (EDFAs) fit anywhere in an optical network for enhancing
signals without electronics.
This invention overcame the most fundamental disadvantage of
optical networks compared to electronic networks. You can tap into an
electronic network as often as desired without eroding the voltage
signal. Although resistance and capacitance will leach away the
current, there are no splitting losses in a voltage divider. Photonic
signals, by contrast, suffer splitting losses every time they are
tapped; they lose photons until eventually there are none left. The
cheap and compact all-optical amplifier solves this problem. It is an
invention comparable in importance to the integrated circuit.
Just as the integrated circuit made it possible to put an entire
computer system on a single sliver of silicon, the all-optical amplifier
makes it possible to put an entire system on a seamless seine of
silica–glass. Unleashing the law of the telecosm, it makes possible a
new global economy of bandwidth abundance.
Five years ago when I first celebrated the radical implications of
erbium-doped amplifiers, skepticism reigned. I was summoned to Bellcore,
where the first optical networks had been built and then abandoned, to
learn the acute limits of the technology from Charles Brackett and his
team. I had offered the vision of a broadband fibersphere–a worldwide
web of glass and light–where computer users could tune into favored
frequencies as readily as radios tune into frequencies in the atmosphere
today. But Brackett and other Bellcore experts told me that my basic
assumption was false. It was no simpler, they said, to tune into one of
scores of frequencies on a fiber than to select time slots in a
time-division-multiplexed (TDM) bitstream.
Indeed, electronic switching technology was moving faster than
optical technology. In the face of the momentum and installed base of
electronic switching and multiplexing, the fibersphere with hundreds of
tunable frequencies would remain a fantasy, like Ted Nelson’s Xanadu.
In 1997 the fantasy is coming true around the world. Xanadu has
become the World Wide Web. The erbium-doped fiber amplifier is an
explosively growing $250 million business. Electronic TDM seems to
have topped out at 2.5 gigabits a second. TDM gear has suffered a
series of delays and nagging defects and so far has failed in the market.
Electronic TDM failed not only because it pushed the envelope of
electronics but also because it violated the new paradigm. In
single-mode fiber, the two key impediments are nonlinearities in the
glass and chromatic dispersion (the blurring of bit pulses because even
in a single band different frequencies move at different speeds).
Chromatic dispersion increases by the square of the bit rate, and the
impact of nonlinearities rises with the power of the signal.
High-powered, high-bit-rate TDM flunked both telecosm tests. By
contrast, wavelength-division multiplexing (WDM) follows the laws of
the telecosm; it succeeds by wasting bandwidth and stinting on power.
WDM takes some 33% more bandwidth per bit than TDM, but it reduces power
to combat nonlinearity and divides the bitstream into multiple
frequencies in order to combat dispersion. Thus it can extend the
distance or increase capacity by a factor of four or more today and can
lay the foundations for the fibersphere tomorrow.
In 1996 the new fiber paradigm emerged in full force. Parallel
communications in all-optical networks, long depicted as a broadband
pipe dream, crushed all competitors and became the dominant source of
new bandwidth in the world telecom network. The year began with a
trifold explosion at the Conference on Optical Fiber Communication in
San Jose when three companies–Lucent Technologies’ Bell Labs, NTT Labs,
and Fujitsu–all announced terabit-per-second WDM transmissions down a
single fiber. Sprint confirmed the significance of the laboratory
breakthroughs by announcing deployment of Ciena’s MultiWave 1600 WDM
system, so called because it can increase the capacity of a single fiber
thread by 1,600%.
The revolution continues in 1997. At the beginning of January,
NEC declared that by increasing the number of bits per hertz from one to
three, it had raised the laboratory WDM record to three terabits per
second. During 1996, MCI had increased the speed of its Internet
backbone by a factor of 25, from 45 megabits a second to 1.2 gigabits.
On January 6, Fred Briggs, chief engineering officer at MCI, announced
that his company is in the process of installing new WDM equipment from
Hitachi and Pirelli that increases the speed of its phone network
backbone to 40 gigabits per second. Accelerating MCI’s previous plans
by some two years, the new system will use a more limited form of
wavelength-division multiplexing to put four 10-gigabit in-cause
formation streams on a single fiber thread.
The first deployment will use existing facilities on a 275-mile
route between Chicago and St. Louis, but the technology will be extended
to the entire network. This move will consummate a nearly thousandfold
upgrade of the MCI backbone, from 45 megabits per second to 40 gigabits,
within some 36 months. Ciena, meanwhile, has announced technology that
allows transmission of 100 gigabits per second.
Its February IPO was the most important since Netscape (market
cap at the end of the first trading day: $3.4 billion). Why? Ciena is
the industry leader in open standard WDM gear. During the first six
months the MultiWave 1600 was available, through October 1996, the firm
achieved $54.8 million in sales and $15 million in net income. (Lucent
is believed to be the overall leader with more than $100 million of
mostly proprietary AT&T systems.) At the same time, the trans-Pacific
consortium announced that it would deploy 100-gigabit-per-second fiber
in its new link between the United States and Asia.
A powerful new player in these markets will be Tellabs, currently
the fastest-growing supplier of electronic digital cross-connect switches
and other optical switching gear. In a further coup, following its
purchase of broadband digital radio pioneer Steinbrecher, Tellabs has
signed up all 12 principals in IBM’s all-optical team. Headed by Paul
Green, recent chairman of the IEEE Communications Society and author of
the leading text on fiber networks, and by Rajiv Ramaswami, coauthor of
a new 1997 text on the subject, the IBM group built the world’s first
fully functioning all-optical networks (AONs), the Rainbow series.
Tellabs now owns the 11 AON patents and 100 listed technology disclosures
of the group.
The implications of the WDM paradigm go beyond simple data pipes.
The greatest impact of all-optical technology will likely come in
consumer markets. A portent is Artel Video Systems of Marlborough,
Massachusetts, which recently introduced a fiber-based WDM system that
can transmit 48 digital video channels, 288 CD-quality audio bitstreams,
and 64 data channels on one fiber line. Aggregating contributions from
a variety of content sources–each on different fiber wavelengths–and
delivering them to consumers who tune into favored frequencies on
conventional cable, the Artel system represents a key step into the
fibersphere. It can be used for new services by either cable TV
companies or telcos.
The deeper significance of the Artel product, however, is its use
of bandwidth as a replacement for transistors and switches. The Artel
system works on dark fiber without compression. The video uses
200-megabit-per-second bitstreams (compare MPEG2 at 4 to 6 megabytes
per second) that permit lossless transmissions suitable for medical
imaging, and obviate dedicated processing of compression codes at the
two ends.
A move to massively parallel communications analogous to the move
to parallel computers, all-optical networks promise nearly boundless
bandwidth in fiber. According to Ewart Lowe of British Telecom, whose
labs at Martlesham Heath in Ipswich have been a fount of all-optical
technology, the new paradigm will reduce the cost of transport by a
factor of 10. For example, the optoelectronic amplifiers previously
used in fiber networks entailed nine power-hungry bipolar microchips
for each wavelength, rather than a simple loop of doped silica that
covers scores of wavelengths.
As these systems move down through the network hierarchy, the
growth of network bandwidth and cost-effectiveness will not only
outpace Moore’s law, it will also excel the rise in bandwidth within
computers–their internal "buses" connecting their microprocessors
to memory and input-output.
While MCI and Sprint move to deploy technology that functions at
40 gigabits a second, current computers and workstations command buses
that run at a rate of close to 1 gigabit a second. This change in the
relationship between the bandwidth of networks and the bandwidth of
computers will transform the architecture of information technology.
As Robert Lucky of Bellcore puts it, "Perhaps we should transmit signals
thousands of miles to avoid even the simplest processing function."
Lucky implies that the law of the telecosm eclipses the law of the
microcosm. Actually, the law of the microcosm makes distributed
computers (smart terminals) more efficient regardless of the cost of
linking them together. The law of the telecosm makes broadband networks
more efficient regardless of how numerous and smart are the terminals.
Working together, however, these two laws of wires and switches impel
ever more widely distributed information systems, with processing and
memory in the optimal locations.
WHAT SHOULD THE MAJOR PLAYERS DO NOW?
FOR THE TELEPHONE COMPANIES, the age of ever smarter terminals
mandates the emergence of ever dumber networks. Telephone companies
may complain of the large costs of the transformation of their system,
but they command capital budgets as large as the total revenues of the
cable industry. Telcos may recoil in horror at the idea of dark fiber,
but they command webs of the stuff 10 times larger than any other
industry. Dumb and dark networks may not fit the phone company
self-image or advertising posture. But they promise larger markets
than the current phone company plan to choke off their own future in the
labyrinthine nets of an "intelligent switching fabric" always behind
schedule and full of software bugs.
Telephone switches (now 80% software) are already too complex to
keep pace with the efflorescence of the Internet. While computers become
ever more lean and mean, turning to reduced instruction-set processors
and Java stations, networks need to adopt reduced instruction-set
architectures. The ultimate in dumb and dark is the fibersphere now
incubating in their magnificent laboratories.
The entrepreneurial folk in the computer industry may view this
wrenching phone company adjustment with some satisfaction. But computer
firms must also adjust. Now addicted to the use of transistors to solve
the problems of limited bandwidth, the computer industry must use
transistors to exploit the nearly unlimited bandwidth. When home-based
machines are optimized for manipulating high-resolution digital video at
high speeds, they will necessarily command what are now called
supercomputer powers. This will mean that the dominant computer
technology will first emerge not in the office market but in the
consumer market. The major challenge for the computer industry is to
change its focus from a few hundred million offices already full of
computer technology to a billion living rooms now nearly devoid of it.
Cable companies possess the advantage of already owning dumb
networks based on the essentials of the all-optical model of broadcast
and select–of customers seeking wavelengths or frequencies rather than
switching circuits. Cable companies already provide all the programs
to all the terminals and allow them to tune in to the desired messages.
But the cable industry cannot become a full-service supplier of
telecommunications unless the regulators give up their ridiculous
two-wire dream in which everyone competes with cable and no one makes
any money. Cash-poor and bandwidth-rich, cable companies need to
collaborate with telcos–which are cash-rich and bandwidth-poor–in a
joint effort to create broadband systems in their own regions.
In all eras, companies tend to prevail by maximizing the use of
the cheapest resources. In the age of the fibersphere, they will use
the huge intrinsic bandwidth of fiber, all 25,000 gigahertz or more, to
simplify everything else. This means replacing nearly all the hundreds
of billions of dollars’ worth of switches, bridges, routers, converters,
codecs, compressors, error correctors, and other devices, together with
the trillions of lines of software code, that pervade the intelligent
switching fabric of both telephone and computer networks.
The makers of all this equipment will resist mightily. But there
is no chance that the old regime can prevail by fighting cheap and
simple optics with costly and complex electronics and software.
The all-optical network will triumph for the same reason that the
integrated circuit triumphed: It is incomparably cheaper than the
competition. Today, measured by the admittedly rough metric of mips per
dollar, a personal computer is more than 2,000 times more cost-effective
than a mainframe. Within 10 years, the all-optical network will be
thousands of times more cost-effective than electronic networks. Just
as the electron rules in computers, the photon will rule the waves of
communication.
I know people would not write it..But worth a try:)
um… i really doubt that people will write you a summary… just do it yourself
January 30th, 2010 at 8:36 pm
um… i really doubt that people will write you a summary… just do it yourself
References :
January 30th, 2010 at 8:53 pm
Nope, sorry, it’s a lot to read and write, and I’ve got my own homework to do =(
References :