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Date: Tue, 13 Dec 94 20:37:48 CST
From: telecom@delta.eecs.nwu.edu (TELECOM Digest (Patrick Townson))
Message-Id: <9412140237.AA02774@delta.eecs.nwu.edu>
To: telecom
Subject: The Bandwidth Tidal Wave by George Gilder
Here is another in the excellent series of essays by George Gilder. This
one comes from his newest book, Telecosm, to be published next year.
I am really pleased to send this out to the net and the Digest mailing
list. Like other articles by Gilder, this will be on permanent display
in the Telecom Archives. As before, Gordon Jacobson will introduce the
text.
PAT
Date: Thu, 08 Dec 1994 18:20:39 -0500
From: gaj@portman.com (Gordon Jacobson)
Subject: Gilder's 10th Telecosm Article - The Bandwidth Tidal Wave
This series of articles by George Gilder provide some interesting
technological and cultural background that helps prepare readers to
better understand and place in proper perspective the events relative
to the National Data Super Highway, which are unfolding almost daily
in the national press. I contacted the author and Forbes and as the
preface below indicates obtained permission to post on the Internet.
Please note that the preface must be included when cross posting or
uploading this article.
The following article, The Bandwidth Tidal Wave, was
first published in Forbes ASAP, December 5, 1994.
It is a portion of George Gilder's book, Telecosm,
which will be published next year by Simon & Schuster,
as a sequel to Microcosm, published in 1989 and Life
After Television published by Norton in 1992.
Subsequent chapters of Telecosm will be serialized in
Forbes ASAP.
THE BANDWIDTH TIDAL WAVE
BY
GEORGE GILDER
Craig Mundie of Microsoft thinks that Tiger,
his video-on-demand operating system, signals
a fundamental shift in the computer industry.
Ruling the new era will be bandwidth measured
in billions of bits per second rather than in
the millions of instructions per second of
current computers.
"We'll have infinite bandwidth in a decade's time."
-- Bill Gates, PC Magazine, Oct. 11, 1994.
ANDREW GROVE, TITAN OF INTEL, is widely known for his belief, born
in the vortex of the Hungarian Revolution and honed in the trenches of
Silicon Valley, that "only the paranoid survive."$ If so, the Intel
chief may soon need to resharpen the edges of fear that have driven
his company to the top. Looming on the horizons of the global
computer industry that Grove now shapes and spearheads is a gathering
crest of change that threatens to reduce the micropocessor's supremacy
and reestablish the information economy on new foundations. Imparting
a personal edge to the challenge are the restless energies of
Microsoft's Bill Gates and Tele-Communications Inc.'s John Malone,
providing catalytic capital and leadership for the new tides of the
telecosm.
Grove's response is seemingly persuasive. "We have state-of-the-art
silicon technology, state-of-the art microprocessor design skills and
we have mass production volumes." These huge assets endow Intel as a
global engine of growth with 55% margins and more than 80% market
share in the single most important product in the world economy. Why
indeed should Grove worry?
One word only may challenge him and with him much of the existing
computer establishment. Let us paraphrase a 1988 speech by John
Moussouris, chairman and chief executive of the amazing Silicon Valley
startup MicroUnity, which gains a portentous heft from being financed
heavily by Gates and Malone: If the leading sage of computer design,
in his last deathbed gasp, wanted to impart in one word all of his
accumulated wisdom about the coming era to a prodigal son rushing home
to inherit the business, that one word would be "bandwidth." Andy
Grove knows it well. Early this year he memorably declaimed: "If you
are amazed by the fast drop in the cost of computing power over the
last decade, just wait till you see what is happening to the cost of
bandwidth."
Eric Schmidt, chief technical officer of Sun Microsystems, is one
of the few men who have measured this coming tide and mastered some of
its crucial implications. His key insight is that the onrush of
bandwidth abundance overthrows Moore's Law as the driving force of
computer progress. Until now progress in the computer industry has
ridden the revelation in 1979 by Intel co-founder Gordon Moore that
the density of transistors on chips, and thus the price-performance of
computers, doubles every 18 months. Soon, however, Schmidt ordains,
bandwidth will be king.
Bandwidth is communications power -- the capacity of an information
channel to transmit bits without error in the presence of noise. In
fiber optics, in wireless communications, in new dumb switches, in
digital signal processors, bandwidth will expand from five to 100
times as fast as the rise of microprocessor speeds. With the rapid
spread of national networks of fiber and cable, the dribble of
kilobits (thousands of bits) from twisted-pair telephone lines is
about to become a firehose of gigabits (billions of bits). But the PC
is not ready. Attach the firehose to the parallel port of your
personal computer and the stream of bits becomes a blast of data
smithereens.
TSUNAMI OF GIGABITS
The bandwidth bottleneck of telephone wires has long allowed the
computer world to live in a strange and artificial isolation. In the
computer world, Moore's Law has reigned. At its awesome exponential
pace, computer price-performance would increase some one hundredfold
every 10 years. This means that for the price of a current 100 mips
(millions of instructions per second) Pentium machine, you could buy a
computer in 2004 running 10 billion instructions per second. Since
today the fastest bit streams routinely linked to computers run 100
times slower, at 10 megabits per second on an Ethernet, 10 bips seems
adequate as a 10-year target. All seems fine in computer land, where
users rarely wonder what happens after the wire reaches the wall.
In the face of the 10 times faster increase in bandwidth, however,
Moore's Law seems almost paltry. The rise in bandwidth does not
follow the smooth incremental ascent that the heroic exertions,
inventions and investments of Andy Grove and his followers have
maintained in microchips. bandwidth bumps and grinds and then
volcanically erupts. The communications equivalent of those 10 bips
that would take 10 years to reach according to the existing trend
would be 10-gigabit-per-second connections to their corporate
customers next year.
During the very period of apparent bandwidth doldrums during the
1980s, phone companies installed some 10 million kilometers of optical
fiber. So far only an infinitesimal portion of its potential
bandwidth has been delivered to customers. Moussouris estimates that
the bandwidth of fiber has been exploited one million times less fully
than the bandwidth of coax or twisted pair copper.
Nonetheless, the tide is now gathering toward a crest. This year,
MCI offers its corporate customers access to a fiber connection at 2.4
gigabits per second. Next year that link will run at 10 gigabits per
second for the same price. Two years after that it is scheduled to
rise to 40 gigabits per second. Meanwhile, at Martlesham Heath in the
United Kingdom, home of British Telecom's research laboratories, Peter
Cochrane announced in early September that he could send some 700
separate wavelength streams in parallel down a single fiber-optic
thread the width of a human hair. Peter Scovell of Northern Telecom's
Bell Northern Research facility declares that by using "solitons"--an
exotic method of keeping the bits intact at high speeds through a kind
of surface tension counterbalancing dispersion in the fiber--it will
be possible to carry 2.4 gigahertz (billions of cycles per second) on
each wave length stream. That would add up to more than 1,700
gigahertz on every fiber thread.
Blocking such bandwidths until recently was what is called in the
optics trade the "electronic bottleneck." The light signals had to be
converted to electronic pulses every 35 kilometers in order to be
amplified and regenerated. Thus fiber optics could not function any
faster than these electronic amplifiers did, or between two and 10
gigahertz. In the late 1980s, however, a team led by David Payne of
the University of Southampton pioneered the concept of doping a fiber
with the rare earth element erbium, to create an all-optical broadband
amplifier. Perfected at Bell Labs, NTT and elsewhere, this device
overcomes the electronic bottleneck and allows communications entirely
at the speed of light.
IBM's optical guru Paul Green prophesies that within the next
decade or so it will be possible to send some 10,000 wavelength
streams down a single fiber thread. Long prophesied by fiber optics
pioneer Will Hicks, these developments remain mostly in the esoteric
domains of optical laboratories. But IBM recently installed its first
all-optical product -- its MuxMaster -- for a customer running 20
wavelengths on a fiber connecting offices in New York to a backup tape
drive in New Jersey. Telephone companies from Italy to Canada are now
deploying erbium-doped amplifiers. Long the frenzied pursuit of
telecom laboratories from Japan to Dallas and government bodies from
ARPA to NTT (now turning private), all-optical networks have become
the object of entrepreneurial startups, such as Ciena and Erbium
Networks.
Returning from the ethers of innovation to existing broadband
technology connecting to people's homes, Craig Tanner of CableLabs in
Louisville, Colo., maintains that a typical cable coax line can
accommodate two-way streams of data totaling eight gigabits per
second. In Cambridge and other eastern Massachusetts cities,
Continental Cablevision is now taking the first steps toward
delivering some of this bandwidth for Andy Grove's PC users. Today,
using Digital Equipment's LANCity broadband two-way cable modems,
David Fellows, Continental's chief technical officer, can offer 10
megabits per second Ethernet capability 70 miles from your office.
That increases the current 9.6 kilobits per second speeds of most
telephone modems by a factor of 1,000.
The most important short-term contributor to the tides of bandwidth
is a new communications technology called asynchronous transfer mode.
ATM is to telecommunications what containerization is to transport.
It puts everything into same-sized boxes that can be readily handled
by automated equipment. Just as containerization revolutionized the
transport business, ATM is revolutionizing communications. In the
case of ATM, the boxes are called cells and each one is 53 bytes long,
including a five-byte address. The telephone industry chose 53 bytes
as the largest possible container that could deliver real-time voice
communications. But the computer industry embraced it because it
allows fully silicon switching and routing. Free of complex software,
small packets of a uniform 53 bytes can be switched at enormous speeds
through an ATM network and dispatched to the end users on a fixed
schedule that can accommodate voice, video and data, all at once.
Available at rates of 155 megabits per second and moving this year
to 622 megabits and 2.4 gigabits, ATM switches from Fujitsu, IBM,
AT&T, Fore Systems, Cisco Systems, SynOptics Communications and every
other major manufacturer of hubs and routers will swamp the ports of
personal computers over the next five years.
Why should all this bandwidth arouse the competitive fire of Andy
Grove? The new explosions of bandwidth enable interactive multimedia
and video, riding on radio frequencies, into every household --
through the air from satellites and terrestrial wireless systems,
through fiberoptic threads and cable TV and even phone-company coax.
If the personal computer cannot handle these streams, John Malone's
set-top boxes, Sega or Nintendo game machines or Bill Gates's new
communications technology will. A communications technology that can
manage multimedia in full flood can also in time relegate one of
Grove's CPUs to service as a minor peripheral. The huge promise of
the PC industry, with its richness of productivity tools and cultural
benefits, could give way to an incoherent babel of toys, videophones
and 3D games.
Redeeming the new era for the general-purpose PC entails overcoming
the technical culture and mindset of bandwidth scarcity. In today's
world of bandwidth scarcity, arrays of special-purpose microprocessors
constantly use their hard-wired computer cycles to compensate for the
narrow bandwidth of existing channels and to make up for the small
capacity of the fast, expensive memories where the data must be
buffered or stored on the way. This is the world that Intel dominates
today--a world of CPUs incapable of handling full multimedia and radio
frequency demands, a world of narrowband four-kilohertz pipes to the
home accessed by modems at 9.6 kilobits per second and a world of what
Moussouris call arrays of "twisty little processors," such as MPEG
(Motion Picture Experts Group) decoders from C-Cube and IIT, graphics
accelerators from Texas Instruments and an array of chips from Intel.
By fixing the necessary algorithms in hardware, these devices
bypass the time-consuming tasks of retrieving software instructions
and data from memory. Thus these chips can perform their functions at
least 100 times faster than more general-purpose devices, such as
Intel's Pentium, that use software. But all this speed comes at the
cost of rigid specialization. An MPEG-1 processor cannot even decode,
MPEG-2. When the technology changes, you have to replace the chip.
Such special-purpose devices now handle the broadband heavy lifting
for video compression and decompression, digital radio processing,
voice and sound synthesis, speech recognition, echo cancellation,
graphics acceleration and other functions too demanding for the
central processor.
By contrast, contemplate a world of bandwidth abundance. In a
world of bandwidth abundance, specialized, hard-wired processing will
be mostly unnecessary. In the extreme case, images can flow
uncompressed through the network and onto the display. Bandwidth will
have obviated thousands of mips of processing. The microprocessor
instead can focus on managing documents on the screen, popping up
needed information from databases, performing simulations or
visualizations and otherwise enriching the conference. The arrival of
bandwidth abundance transforms the computing environment.
Led by Grove's and Intel's bold investments in chip-making
capability -- some $ 2.4 billion in 1994 alone--the entire information
industry has waxed fat and happy on the bonanzas of Moore's Law. Now,
however, some industry leaders are gasping for breath. Exkhard
Pfeiffer of Compaq has denounced Intel's avid campaign to shift
customers toward the leading-edge processors such as Pentium,
embodying the latest Moore's Law advances. Gordon Moore himself has
recently questioned whether the pace of microchip progress can
continue in the face of wafer factory costs rising toward $ 2 billion
for a typical "fab." He has pronounced a new Moore's Law: The costs of
a wafer fab double for each new generation of microprocessor.
Sorry, but the new world of the telecosm offers no rest for weary
microchip magnates or future-shocked PC producers. Driven by the new
demands of video and multimedia, the pace of advance will now
acclerate sharply rather than slow down.
FEEDING THE TIGER
Contemplate the advance of the Tiger, Microsoft's all-software
scheme for video-on-demand based entirely on PCs. Although Tiger has
been presented as merely another way to build a "movie central" for
cable headends or telco central offices, its real promise is not to
redeem the existing centralized structure of video but to allow any PC
owner to create a headend in the kitchen for video-on-demand. Today,
such capability would mean buying a supercomputer plus an array of
expensive boards containing special-purpose processors. Tiger's
consummation as a popular product therefore will require a new regime
of semiconductor progress.
Driven by this imperative, a pioneering combine of Gates, Malone
and Moussouris is making an audacious grab for supremacy in the
telecosm. Just three miles from Intel and fueled by ideas from a 1984
defector from an Intel fabrication team, Moussouris's MicroUnity is a
flagrantly ambitious Sunnyvale, Calif., startup launched in 1988.
Fueled by some $ 15 million from Microsoft and $ 15 million from TCI,
among several other rumored backers, it plans a transformation of
chip-making for the age of the telecosm, optimized for communications
rather than computations.
MicroUnity's goal is a general-purpose mediaprocessor, software
programmable, that can run at no less than 400 billion bits per second
-- some hundreds of times faster than a Pentium -- and perform all the
functions currently done in special-purpose multimedia devices.
Escaping the tyranny of fixed hardware standards, the mediaprocessor
could receive decompression codes and other protocols, algorithms and
services over the network with the video to be displayed in real time.
THE GREAT BANDWIDTH SWITCH
In launching Tiger and MicroUnity, Gates and Malone are signaling a
fundamental shift in the industry. Ruling the new era will be
bandwidth or communications power, measured in billions of bits per
second rather than in the millions of instructions per second of
current computers. The telecosmic shift from mips to bandwidth, from
storage-oriented computing to communications processing, will change
the entire structure of information technology.
In the past, the industry has been driven by increases in computer
power embodied in new generations of microprocessors--from the 8086 to
the Pentium and on to the P-6 and new Reduced Instruction Set
screamers such as the Power PC, Digital Equipment's Alpha and Silicon
Graphics new R-1000 (the latest in the family from Moussouris's
previous company Mips Computer, now owned by Silicon Graphics).
External computer networks typically run much more slowly than
internal networks, the backplane buses connecting microprocessors,
memories, keyboards and screens. These buses race along at some 40
megabits per second, up to Intel's new giabit-per-second PCI bus.
Even when computers are linked in local area networks in particular
buildings at 10 megabit-per-second Ethernet speeds, they face a
communications cliff at LAN's end: the four-kilohertz wires of the
telephone company. Under this regime, the processor is king and
Moore's Law dictates the pace of change.
In the age of the telecosm, however, all these rules collapse.
When the network increasingly runs faster than the processors and
buses in the PC, the computer "hollows out," in the words of Eric
Schmidt. The network becomes the bus and any set of interconnected
processors and memories can become a computer regardless of their
location. In this bandwidth-driven world, the key chips are
communications processors, such as digital signal processors (DSPs)
and MicroUnity's mediaprocessors, which must function at the pace of
the network firehose rather than at the pace of the Pentium.
For the last five years, communications processors have indeed been
improving their price/performance tenfold every two years -- more than
three times as fast as microprocessors. This kind of difference add
up. Soaring DSP capabilities have already made possible the achievement
of many new digital technologies previously unattainable. Among them
are digital video compression, video teleconferencing, broadband
digital radios pioneered by Steinbrecher (see Forbes ASAP, April 11,
1994), digital echo cancellation and spread-spectrum cellular systems
that allow 100% frequency reuse in every cell. All these schemes
require processing speeds far in excess of the bit rate of the
information.
For example, in accord with the prevailing MPEG standards, digital
video compression produces a bit stream running at between 1.5 and six
megabits per second. But in order to produce this signal manageable
by a 100 mips Pentium, a supercomputer or special-purpose machine must
process raw video bit flowing 100 times as fast as the compressed
format -- uncompressed video at a pace of 150 to 600 megabits per
second. The complex and exacting process of compressing this onrush
of bits -- compensating for motion, comparing blocks of pixels for
redundancy, smoothing out the flow of data--entails computer
operations running 1,000 times as fast as the raw video bits. That
is, the video compression algorithm requires a processing speed of
between 150 and 600 gigabits per second -- hundred of times faster than
the Pentium.
Similarly, just to digitize radio signals requires a sampling rate
twice as fast as the radio frequency -- at a time when new wireless
personal communications systems are moving to the two gigahertz bands
and wireless cable is moving to 28 gigahertz. A broadband digital
radio must handle some large multiple of the highest frequency it will
process. Code division multiple access (CDMA) cellular systems depend
on a spreading code at least 100 times faster than the bit rate of the
message.
In order to feed the Tiger and other such bandwidth-hungry systems,
communications processors will have to continue this breathtaking
binge of progress beyond the bounds of the microcosm. Grove does not
believe this possible. He contends that the surge in DSP will dwindle
and converge with Moore's Law, allowing the central processor to suck
in functions currently performed in digital signal processors and
other communications chips. DSP is nice, Grove observes, "but it is
not free--unless, that is, it is performed in the Intel CPU, obviating
the need to buy a DSP chip at all.
But in an era when the network advances faster than the CPU, it is
more likely that communications processors will gradually "suck in"
and "hollow out" the functions of the CPU, rather than the other way
around. Echoing Sun's perennial slogan, Schmidt predicts that the
network will become the computer. In this era, Moore's Law and the
law of the microcosm are no longer the driving force of progress in
information technology. Bandwidth is king.
As the great pioneer of communications theory Claude Shannon wrote
in 1948, bandwidth is a replacement for switching. Since ultimately a
microprocessor is a set of millions of transistor switches inscribed
on a chip, bandwidth can even serve as a substitute for mips. With
sufficient communication, engineers can duplicate any computer network
topology they want. As the network becomes the computer, they thus
redefine the optimal architectures of computing. As an example, take
the problem of video-on-demand now being confronted by every major
company in the industry from IBM to Microsoft.
In 1992, Microsoft assigned this problem to Craig Mundie, a veteran
of Data General in Massachusetts, who had gone on to found Alliant
Computer, one of the more successful of the massively parallel
computer firms. As a supercomputer man, Mundie initially explored a
hardware solution, hiring a team of computer designers from
Supercomputer Systems Inc. SSI was Steve Chen's effort to follow up
on his successes at Cray Research with a machine for IBM. Although
IBM ultimately closed SSI down, Chen commanded some of the best talent
in supercomputers. Mundie hired George Spix and a team from SSI.
LOOKING TO SOFTWARE
On the surface, video-on-demand seems a super-computer task. It
entails taking tens of thousands of streams of digital images,
smoothing them into real-time flows, and switching them to the
customers requesting them. Essentially huge hierarchies of storage
devices, including fast silicon memories, connected through a
specialized switching fabric to arrays of fast processors,
supercomputers seem perfectly adapted to video-on-demand, which as
Bill Gates explains, is "essentially a switching problem." This is the
solution chosen by Oracle Systems, using its nCube supercomputer, and
by Silicon Graphics, employing its PowerChallenge server.
According to Mundie, the SSI team developed an impressive video
server design. But they soon discovered they were in the wrong
company. As Gates told Forbes ASAP, "Microsoft looks for a software
solution to all problems. IBM looks for a mainframe hardware
solution. Larry Ellison owned a supercomputer company so he looked
for that solution. Fortunately for us, software solutions are the
most scalable, flexible, fault-tolerant and low cost."
Enter Rick Rashid, a professor from Carnegie Mellon and designer of
the Mach kernel adopted by Next, IBM and the Open Software Foundation
and incorporated in part in Mircosoft's Windows NT operating system.
Rashid joined Microsoft in September 1991 and began to focus on
video-on-demand in 1992. Like most other people confronting this
challenge, he first assumed that the huge bit streams involved would
require specialized hardware -- RAID (redundant arrays of inexpensive
disk) storage, fast buffer memories and supercomputer-style switches.
Soon, however, he came to the conclusion that progress in the personal
computer industry would enable an entirely software solution.
For example, the memory problem illustrates a tradeoff between
bandwidth and processing speed. Expensive hierarchies of RAID drives
and semiconductor buffer memories managed by complex controller logic
can speed the bit streams to the switch at the necessary pace. But
Rashid and Mundie saw that bandwidth offered a cheaper solution.
Through clever software, you could "stripe" the film bits across large
arrays of conventional disk drives and gain speed through bandwidth.
Rather than using one fast memory, plus fast processors, and
hard-wired fault tolerance to send the movie reliably to a customer,
you spread the images across arrays of cheap, slow disk
drives -- Seagate Barracudas -- which, working in parallel, offer
bandwidth and redundancy limited only the the number of devices.
Having dispensed with the idea of contriving expensive hardware
solutions for the memory problem, Rashid recognized that with Windows
NT he commanded an operating system with real-time scheduling
guarantees that laid the foundation for a software solution. On it,
he could proceed to build Tiger as a continuous digital stream
operating system.
Liberated from special-purpose hardware, the team could revel in
all the advantages of using off-the-shelf personal computer
components. Mundie explains: "The personal computer industry commands
intrinsic volume and a multisupplier structure that takes anything in
its path and drives its costs to ground." A burly entrepreneur of
massively parallel supercomputers, Mundie became a fervent convert to
the manifest destiny of the PC to dominate all other technologies in
the race to multimedia services, grinding all costs and functions into
the ground of microprocessor silicon.
Video-on-demand has been heralded as the salvation of the
television industry, the supercomputer industry, the game industry,
the high-end server industry. It has been seen as Microsoft's move
into hardware. Yet nowhere in the Tiger Laboratory in Building Nine
is there any device made by any TV company, supercomputer firm,
workstation company, or Microsoft itself. On one side of the room are
12 monitors. On the other side are 12 Compaq computers piled on top
of each other, said to be simulating set-top boxes. Next to these are
a pile of Seagate Barracuda disk drives, each capable of holding the
nine gigabytes of video in three high-resolution compressed movies.
Next to them are another pile of Compaq computers functioning as video
servers.
All this gear works together to extend Microsoft's long mastery of
the science of leverage, getting most of the world to drive costs to
ground -- or grind cost into silicon -- while the grim reapers of Redmond
collect tolls on the software. Exploiting another of Sun Microsystems
co-founder Bill Joy's famous laws -- "The smartest people in every field
are never in your own company" -- Gates has contrived to induce most of
the personal computer industry, from Bangalore to Taiwan, to work for
Microsoft without joining the payroll.
In the new world of bandwidth abundance, however, it is no longer
sufficient to leverage the PC industry alone. Gates is now reaching
out to leverage the telephone and network equipment manufacturing
industries as well. Transforming all this PC hardware into a "Tiger"
that can consume the TV industry is an ATM switch. In the Tiger
application, once one ATM switch has correctly sequenced the movie
bits streaming from the tower of Seagate disks, another ATM switch in
a metropolitan public network will dispatch the now ordered code to
the appropriate display. Microsoft's Tiger and its client "cubs" all
march in asynchronous transfer mode.
THE MASTERS OF LEVERAGE
Why is this a brilliant coup? It positions Microsoft to harvest
the fruits of the single most massive and far-reaching project in all
electronics today. Some 600 companies are now active in the ATM
forum, with collective investments approaching $ 10 billion and rising
every year. Not only are ATM switches produced by a competitive swarm
of companies resembling the PC industry, ATM also turns networks of
small computers into scalable supercomputers. It combines with
fiber-optic links to provide a far simpler, more modular and more
scalable solution than the complex copper backplane buses that perform
the same functions in large computers. ATM and fiber prevail by using
bandwidth as a substitute for complex protocols and computations.
Microsoft Technical Director Nathan Myhrvold points to the Silicon
Graphics PowerChallenge superserver as a contrast. "They have a bus
that can handle 2.4 gigabytes per second and which is electrically
balanced to take a bunch of add-in cards (for processor and memory)."
The complexities of this solution yield an expensive machine, costing
more than $ 100,000, with specialized DRAM boards, for example, that
cost 10 times as much per megabyte as DRAM in a PC.
This problem is not specific to Silicon Graphics. All
supercomputers with multiple microprocessors linked with fast buses
face the same remorseless economics and complexities. By contrast,
the $ 30,000 Fore systems ATM switch being used in Tiger prototypes --
together with the PCI buses in the PCs on the network -- supply the
same 2.4 gigabytes per second of bandwidth that the PowerChallenge
does. And, as Myhrvold points out, "ATM prices are dropping like a
stone."
The Microsoft sage explains: ATM switches linked by fiber optic
lines are far more efficient at high bandwidth than copper buses on a
backplane. ATM allows "fault tolerance and other issues to be handled
in software by treating machines (or disks, or even the ATM switch
itself) as being replaceable and redundant, with hot spares standing
by."
As Gates told ASAP, video-on-demand is essentially a switching
problem. You can create an expensive, proprietary, and unscalable
switch using copper lines and complex protocols on the backplane of a
supercomputer, or you can use the bandwidth of fiber optics and ATM as
a substitute for these complexities. You can put the ATM switches
wherever you need them to create a system optimized for any application,
allowing any group of PCs using Windows NT and PCI buses to function
as video clients or servers as desired. As Microsoft leverages the
world, it won't object if the world chooses to lift NT into the
forefront of operating systems in unit sales.
Mundie and his assistant Redd Becker earnestly explain the virtues
of this scheme and demonstrate its robustness and fault tolerance by
disabling several of the disk drives, cubs and servers without
perceptibly affecting the 12 images on the screen. They offer it as a
system to function as a movie central server resembling the Oracle
nCube system adopted by Bell Atlantic, or the Silicon Graphics system
used by Time Warner in its heralded Orlando project. But the Tiger is
fundamentally different from these systems in that it is completely
scalable and reconfigurable, functioning with full VCR interactivity
for a single citizen or for a city. It epitomizes the future of
computing in the age of ATM, a system that will soon operate at up to
2.4 gigabits per second. Two point four gigabits per second is more
than twice as fast as the Intel PCI bus that links the internal
components of a Pentium-based personal computer.
Thus, ATM technology can largely eclipse the difference between an
internal hard drive and an external Barracuda, between a video client
and a video server. To the CPU, a local area network or even a wide
area network running ATM can function as a motherboard backplane.
With NT and Tiger software, PCs will be able to tap databases and
libraries across the world as readily as they can reach their own hard
disks or CD-ROM drives. Presented as an application-specific system
for multimedia or movie distribution in real time, it is in fact a new
operating system for client-server computing in the new age of image
processing.
Gordon Bell, now on Microsoft's technical advisory board, sums up
the future of computing in an ATM world: "We can imagine a network
with a range of PC-sized nodes costing between $ 500 and $ 5,000 that
provide person-to-person communication, television and when used
together (including in parallel), an arbitrarily large computer.
Clearly, because of standards, ubiquity of service and software market
size, this architecture will drive out most other computer structures
such as massively parallel computers, low-priced workstations and all
but a few special-purpose processors. This doomsday for hardware
manufacturers will arrive before the next two generations of computer
hardware play out at the end of the decade. But it will be ideal for
users." And for Microsoft.
For manufacturers of equipment that feeds the Tiger, however, what
Bell calls "doomsday for hardware manufacturers: may well be as
profitable as the current rage of "Doom," the new computer game
infectiously spreading from the Internet into computer stores. The
new Tiger model provides huge opportunities for manufacturers of new
ATM switches on every scale, for PCs equipped with fast video buses
such as PCI, for vendors of network hardware and software, and perhaps
most of all for the producers of the new communications processors.
For all the elegance of the Tiger system, however, Gates
understands that it cannot achieve its goals within the constraints of
Moore's Law in the semiconductor industry. The vision of "any high
school dropout buying PCs and entering the interactive TV business"
cannot prevail if it takes a supercomputer to compress the images and
an array of special-purpose processors to decode, decrypt and
decompress them. Facing an ATM streams of 622 megabits per
second--perhaps uncompressed video, 3-D or multimedia images--Eric
Schmidt points out, a 100 mips Pentium machine would have to process
1.47 million 53-byte cells a second. That means well under 100
instruction cycles to read, store, display and analyze a packet.
Since most computers use many cycles for hidden background tasks, the
Pentium could not begin to do the job. Gate's adoption of Tiger, his
alliance with TCI, his investments in Teledesic, Metricom, and
MicroUnity, all bring home face-to-face with the limits of current
computer technology in confronting the telecosm. With MicroUnity,
however, he may have arrived at a solution just in time.
MicroUnity seems like a throwback to the early years of Silicon
Valley, when all things seemed possible -- when Robert Widlar could
invent a new product for National Semiconductor on the beach in Puerto
Vallarta, and develop a new process to build it with David Talbert and
his wife Dolores over beers on a bench at the Wagon Wheel. It was an
era when scores of semiconductor companies were racing down the
learning curve to enhance the speed and functions of electronic
devices. Most of all, the MicroUnity project is a climactic episode
in the long saga of the industry's struggle between two strategies for
accelerating the switching speeds in computers.
A NEW MOORE'S LAW?
Intel Chairman Gordon Moore recently promulgated a new Moore's Law,
supposedly deflecting the course of the old Moore's Law, which ordains
that chip densities double every 18 months. The new law is that the
costs of a chip factory double with each generation of microprocessor.
Moore speculated that these capital burdens might deter or suppress
the necessary investment to continue the pace of advance in the
industry.
Gerhard ("Gerry") Parker, Intel's chief technical officer, however,
presents contrary evidence. The cost for each new struture may be
approximately doubling as Moore says. But the cost per transistor --
and thus the cost per computer function -- continues to drop by a
factor of between three and four every three years. Not only does the
number of transistors on a chip rise by a factor of four, but the
number of chips sold doubles with every generation of microprocessor,
as the personal computer market doubles every three years. Thus there
will be some eight times more transistors sold by Intel from a Pentium
fab that from a 486 fab. At merely twice the cost, the new fab seems
a bargain.
Of course, Intel gets paid not for transistors but for computer
functions. To realize the benefits of the new fabs, therefore, Intel
must deliver new computer functions that successfully adapt to the era
of bandwidth abundance.
Moreover, it is worth noting that measured in telecosmic terms of
useful terabits per second of bandwidth, a MicroUnity fab ultimately
costing some $ 150 million might generate more added value than a $ 2
billion megafab of Intel.
RETURN TO LOW AND SLOW
Since as a general rule, the more the power, the faster the switch,
you can get speed by using high-powered or exotic individual
components. It is an approach that worked well for years at Cray,
IBM, NEC and other supercomputer vendors. Wire together superfast
switches and you will get a superfast machine.
The other choice for speed is to use low-powered, slow switches.
You make them so small and jam them so close together, the signals get
to their destinations nearly as fast as the high-powered signals.
This approach works well in the microprocessor industry and in the
human brain.
Despite occasional deviations at Cray and IBM, low and slow has
been the secret of all success in semiconductors from the outset.
Inventor William Shockley substituted slow, low-powered transistors
for faster, high-powered vacuum tubes. Gordon Teal at Texas
Instruments replaced fast germanium with slower silicon. Jean Hoerni
at Fairchild spurned the fast track of mountainous Mesa transistors to
adopt a flat "planar" technology in which devices were implanted below
the surface of the chip. Jack Kilby and Robert Noyce then substituted
slow resistors and capacitors as well as slow transistors on
integrated circuits for faster, high-powered devices on modules and
printed circuit boards. Federico Faggin made possible the
microprocessor by replacing fast metal gates on transistors with slow
gates made of polysilicon. Frank Wanlass and others replaced faster
NMOS and PMOS technologies with the 1,000 times slower and 10 times
lower-power Complementary Metal Oxide Semiconductors (CMOS) that now
rule the industry.
Low and slow finds its roots in the very physics of solid state,
separating the microcosm from the macrocosm. Chips consist of complex
patterns of wires and switches. In the macrocosm of electromechanics,
wires were simple, fast, cool, reliable and virtually free; switches
were vacuum tubes, complex, fragile, hot and expensive. In the
macrocosm, the rule was economize on switches, squander on wires. But
in the microcosm, all these rules of electromechanics collapsed.
In the microcosm, switches are almost free -- a few millionths of a
cent. Wires are the problem. However fast they may be, longer wires
laid down on the chip and more wires connected to it translated
directly into greater resistance and capacitance and more needed power
and resulting heat. These problems become exponentially more acute as
wire diameters drop. On the other hand, the shorter the wires the
purer the signal and the smaller the resistance, capacitance and heat.
This fact of physics is the heart of microelectronics. As electron
movements approach their mean free path -- the distance they can travel
"ballistically" without bouncing off the internal atomic structure of
the silicon -- they get faster, cheaper and cooler.
At the quantum level, noise plummets and bandwidth explodes.
Tunneling electrons, the fastest of all, emit virtually no heat at
all. It was a new quantum paradox; the smaller the space the more the
room, the narrower the switches the broader the bandwidth, the faster
the transport the lower the noise. As transistors are jammed more
closely together, the power delay product -- the crucial index of
semiconductor performance combining switching delays with heat
emission -- improves as the square of the number of transistors on a
single chip.
Since the breakthrough to CMOS in the early 1980s, however, the
industry has been slipping away from the low and slow regime. Falling
for the electromechanical temptation, they are substituting fast
metals for slow polysilicon. For better performance, companies are
increasingly turning to gallium arsenide and silicon germanium
technologies. Semiconductor engineers are increasingly crowding the
surface of CMOS with as many as four layers of fast aluminum wires,
with tungsten now in fashion among the speed freaks of the industry .
The planar chips that built Silicon Valley have given way to high
sierras of metal, interlarded with uneven spreads of silicon dioxide
and other insulators. Meanwhile, the power used on each chip is
rising rapidly, since the increasing number of transistors and layers
of metal nullify a belated move to three-volt operation from the five
volts adopted with Transistor Transistor Logic in 1971. And as the
industry loses touch with its early inspiration of low and slow, the
costs of wafer fabrication continue to rise -- to an extent that even
demoralizes Gordon Moore.
In radically transforming the methods of semiconductor fabrication,
John Moussouris and James ("Al") Matthews, MicroUnity's director of
technology, seem to many observers to be embarking on a reckless and
selfdefeating course. But MicroUnity is betting on the redemptive
paradoxes of the microcosm. Returning to low and slow, Moussouris and
Matthews promise to increase peak clock speeds by a factor of five in
the next two years and chip performance by factors of several hundred,
launching communications chips in 1995 that function at 1.2 gigahertz
and perform as many as 400 gigabits per second.
MATTHEWS AND MEAD
In pursuing this renewal of wafer fabrication at MicroUnity,
Matthews has applied for some 70 patents and won about 20 to date. A
veteran of Hewlett-Packard's bipolar process labs who moved to Intel
in the early 1980s and spearheaded Intel's switch to CMOS for the 386
microprocessor, Matthews has also worked as an engineer at
HP-Avantek's gallium arsenide fabs for microwave chips. Commanding
experience in diverse fab cultures, Matthews thus escapes the
cognitive trap of seeing the established regime as a given, rather
than a choice.
At Aventek, Matthews plunged toward the microcosm and prepared the
way for his MicroUnity process after reading an early paper by Carver
Mead, the inventor of the gallium arsenide MESFET transistor. Mead
had prophesied that the behavior of these transistors would
deteriorate drastically if the feature sizes were pushed below
two-tenths of a micron at particular doping levels (technically
impossible at the time). In the mid-1980s, though, Matthews noticed
that these feature sizes were then feasible. Testing the Mead thesis,
he was startled to discover that far from deteriorating below the Mead
threshold, these transistors instead showed "startlingly anomalous
levels of good behavior," marked by high gain and plummeting noise.
Based on this discovery, he created a low-noise,
gigahertz-frequency amplifier for satellite dishes being sold in the
European market. Matthew's process reduced the cost so drasticlly
that Sony officials were said to be contemplating claims of dumping.
Avantek was charging a few dollars for microwave frequency chips that
cost Sony perhaps some hundreds of dollars to make.
Having discovered the "anomalous good behavior" of gallium arsenide
devices pushed beyond the theoretical limits, Matthews at MicroUnity
decided to experiment with bipolar devices. Bipolar devices are
usually used at high power levels with so-called emitter coupled logic
to achieve high speeds in supercomputers and other advanced machines.
Inspired by his breakthrough with gallium arsenide, Matthews believed
that biopolar performance also might be radically different at
extremely low power -- under half a volt and at gate lengths approaching
the so-called Debye limit, near one-tenth of a micron.
Once again, Matthews was startled by "anomalous good behavior" as
processes approached the quantum mechanical threshold. It turned out
that at high frequencies biopolar transistors use far less power even
the CMOS transistors, famous for their low-power characteristics. At
these radio-frequency speeds, however, he discovered that the
transistors could not operate with aluminum wires insulated by oxide.
Therefore, he introduced a technique he had used with fast bipolar and
gallium arsenide devices: gold wires insulated by air. Replacing
oxide insulators with "air bridges" drastically reduces the
capacitance of the wires and allows the transistor to operate at
speeds impossible with conventional device structures.
With these adventures in the microcosm behind him, Matthews was
ready to develop a new process and technology for MicroUnity. Based
on combining the best features of biopolar and CMOS at radially small
geometries, the new technology uses bipolar logic functioning at
gigahertz clock speeds, with CMOS retained chiefly for memory cells
and with gold air bridges for the metalization layers. Perhaps it is
a portent that the gold wires across the top of the chip repeat the
most controversial feature of Jack Kilby's original integrated
circuit. (Matthews is also seeking patents for methods of using
optical communications on the top of a silicon chip.)
In essence, Matthews is returning to low and slow. He is shearing
off the sierras of metal and oxides and restoring the planar surfaces
of Jean Hoerni. Because the surface is flat to a tolerance of
one-tenth of a micron, photolithography gear can function at higher
resolution despite a narrow depth of field. Elimination of the
aluminum sierras also removes a major source of parasitic currents and
transistors and allows smaller polysilicon devices to be implanted
closer together. A major gain from these innovations is a drastic
move to lower power transistors. Rather than using the usual three
volts or five volts, the MicroUnity devices operate at 0.3 volts to
0.5 volts (300 to 500 millivolts). In the microcosm, smaller devices
closer together at lower power is the secret of speed.
Although MicroUnity will not divulge the details of future
products, ASAP calculates on the basis of information from other
sources that the MicroUnity chip can hold more than 10 million
transistors in a space half the size of a Pentium with three million
transistors. With lower power transistors set closer together, the
MicroUnity chip can operate with a clock rate as much as 10 times
faster than most current microprocessors and at an overall data rate
more than 100 times faster. Low and slow results in blazing speed.
For ordinary microprocessor applications, an ultrafast clock is
superfluous. Since ordinary memory technology is falling ever farther
behind processor speeds, fast clocks mean complex arrangements of
cache on cache of fast static RAM and specialized video memory chips.
By using the MicroUnity technology at the relatively slow clock rates
of a Pentium, MicroUnity might be able to produce Pentiums that use
from five to 10 times less power -- enabling new generations of
portable equipment.
MicroUnity, however, is not building a CPU but a communications
processor. In the communications world, the fast clock rate gives the
"mediaprocessor" the ability to couple to broadband pipes using high
radio frequencies. Most crucially, the mediaprocessor can connect to
the radio frequency transmissions over cable coax.
Along with Bill Gates, one of the leading enthusiasts of MicroUnity
is John Malone, who for the last year has been celebrating its
potential to create a "Cray on a tray" for his set-top boxes and cable
modems. For the rest of this decade, most Americans will be able to
connect to broadband networks only over cable coax. Thus the link of
TCI to MicroUnity and to Tiger offers the best promise of an
information infrastructure over the next five years, affording a
potential increase in bandwidth of 250,000-fold over the current
four-kilohertz telephone wires.
The Regional Bell Operating Companies and the cable companies agree
that cable coax is the optimal broadband conduit to homes and that
fiber optics is the best technology for connecting central switches or
headends to neighborhoods. Looping through communities, with a short
drop at each home -- rather than running a separate wire from the
central office to every household -- hybrid fiber-coax networks,
according to a Pacific Bell study can reduce the cost of setup and
maintenance of connections by some 75% and cut back the need for wire
by a factor of 600.
In order to bring broadband video to homes, companies must
collaborate with the cable TV industry. Collaborating with TCI,
Microsoft once again has chosen the correct technology to leverage.
With Digital Equipment, Zenith and Intel all engaged in alliances for
the creation of cable modems -- and several other companies announcing
cable modem projects -- Gates may well be leading the pack in
transforming his company from a computer company into a communications
concern, from the microcosm into the telecosm.
Fiber Miles (Millions)
Deployed in U.S. as of 1993
Local Exchange Carriers 7.28
Inter-Exchange Carriers 2.50
Competitive Access Providers 0.24
Total 10.02
Source: MicroUnity
DRIVING FORCE OF PROGRESS
All the bandwidth in the world, however, will get you nowhere if
your transceiver cannot process it. By returning to the inspiration
of the original Silicon Valley, MicroUnity offers a promising route to
the communications infrastructure of the next century, overthrowing
Moore's Law and issuing the first fundamental challenge to Moore's
company. As Al Matthews puts it: "Bob Noyce [the late Intel founder
with Gordon Moore] is my hero. But there is a new generation at hand
in Silicon Valley today, and this generation is doing things that Bob
Noyce never dreamed of."
Moussouris promises to deliver 10,000 mediaprocessors for set-top
boxes in 1995. As everyone agrees, this is a high-risk project
(although Bill Gates favorably compares MicroUnity's risk to his other
gamble, Teledesic). Even if it takes years for MicroUnity to reach
its telecosmic millennium, the advance of communications processors
continues to accelerate. Already available today, for example, is
Texas Instruments' MVP system -- the first full-fledged mediaprocessor
on one chip. It will function at a mere 30 to 50 megahertz but
performs between two and three billion signal processing steps per
second or roughly between 1,000 and 1,500 DSP mips. Rather than
revving up the clock to gigahertz frenzies, TI gained its performance
through a Multiple Instruction, Multiple Data approach associated with
the massively parallel supercomputer industry. The MVP combines four
64-bit digital signal processors with a 32-bit RISC CPU, a floating
point unit, two video controllers, 64 kilobytes of static RAM cache
and a 64-bit direct memory access controller -- all on one sliver of
silicon, costing some $ 232 per thousand mips in 1995, when Pentiums
will give you a hundred mips for perhaps twice as much.
This does not favor the notion that microprocessors will soon "suck
in" DSPs. DSP mips and computer mips are different animals. As DSP
guru Will Strauss points out, "As a rule of thumb, a microprocessor
mips rating must be divided by about five to get a DSP mips rating."
To equal an MVP for DSP operations, a mictoprocessor would have to
achieve some 5,000 mips.
Designed with the aid of teleconferencing company VTEL and Sony,
the MVP chip can simultaneously encode or decode video using any
favored compression scheme, process audio, faxes or input from a
scanner and perform speech recognition or other pattern-matching
algorithms. While Intel and Hewlett-Packard have been winning most of
the headlines for their new RISC processing alliance, the key
development in the microprocessor domain is the emergence of this new
class of one-chip multimedia communications systems.
One thing is certain. Over the next decade, computer speeds will
rise about a hundredfold, while bandwidth increases a thousandfold or
more. Under these circumstances, the winners will be the companies
that learn to use bandwidth as a substitute for computer processing
and switching. The winners will be the companies that most truly
embrace the Sun slogan: "The network is the computer." As Schmidt
predicts, over the next few years "the value-added of the network will
so exceed the value-added of the CPU that your future computer will be
rated not in mips but in gigabits per second. Bragging rights will go
not to the person with the fastest CPU but to the person with the
fastest network -- and associated database lookup, browsing and
information retrieval engines."
The law of the telecosm will eclipse the law of the microcosm as
the driving force of progress. Springing from the exponential
improvement in the power delay product as transistors are made
smaller, the law of the microcosm holds that if you take any number
(N) transistors and put them on a single sliver of silcon you will get
N squared performance and value. Conceived by Robert Metcalfe,
inventor of the Ethernet, the law of the telecosm holds that if you
take any number (n) computers and link them in networks, you get n
squared performance and value. Thus the telecosm builds on and
compounds the microcosmic law. The power of Tiger, MicroUnity and TCI
comes from fusing the two laws into a gathering tide of bandwidth.
With network technology advancing 10 times as fast as central
processors, the network and its nodes will become increasingly central
while CPUs become increasingly peripheral. Faced with a CPU
bottleneck, multimedia systems will simply bypass the CPU on
broadbands pipes. Circumventing Amdahl's Law, system designers will
adapt their architectures to exploit the high bandwidth components,
such as mediaprocessors, ATM switches and fiber links. In time the
microprocessor will become a vestigial link to the legacy systems such
as word processing and spreadsheets that once defined the machine.
All of this means that while the last two decades have been the epoch
of the computer industry, the next two decades will belong to the
suppliers of digital networks.
The chief beneficiaries of all this invention, however, will be the
people of the world, ascending to new pinnacles of prosperity in an
Information Age. Although many observers fear that these new tools
will chiefly aid the existing rich -- or the educated and smart -- these
technologies have already brought prosperity to a billion Asians, from
India and Malaysia to Indonesia and China, previously mired in penury.
Communications bandwidth is not only the secret of electronic
progress. It is also the heart of economic growth, stretching the
webs of interconnection that extend the reach of markets and the
realms of opportunity. Lavishing the exponential gains of networks,
endowing old jobs with newly productive tools and unleashing
creativity with increasingly fertile and targeted capital, the advance
of the telecosm offers unprecedented hope to the masses of people whom
the industrial revolution passed by.
#####
Regards,
Gordon Jacobson
Portman Communication Services
(212) 988-6288
gaj@portman.com MCI Mail ID: 385-1533
Home Page: http://www.seas.upenn.edu/~gaj1/home.html
Channel One BBS - Cambridge, MA