City of Light: The Story of Fiber Optics

226 CITY OF LIGHT
Although fibers will pass every home in Japan, the phone company won’t
promise to run them the last few hundred feet to connect homes. Instead,
NTT plans to run wires from optical nodes along the street. That isn’t too
much different from American plans.
Will Hicks believes we have barely tapped the potential of fibers. He says
that for $400 to $500 per user, he could build a fiber system to let people
pick from among 5000 video channels for each of three televisions, access
old television shows and a quarter of all the movies ever made, and call up
a wealth of written material. ‘‘I know there aren’t 5,000 TV programs. There
aren’t any at all worth seeing,’’ Hicks says, echoing Isaac Asimov 30 years
earlier. ‘‘But if there were, we could make them available.’’ 46
And there, in a sense, lies the central problem. Fiber optics may be too big
a pipe; it can deliver more information than anyone knows what to do with.
It can deliver an eight-lane freeway of information to our doorstep, when
most of us want only a sidewalk. The Internet and the World Wide Web may
change that. Try to download graphics-laden web pages and you quickly
realize how slowly information trickles through the network. However, you
often don’t do too much better with a bigger pipe; the switches have also
become bottlenecks. And despite all the wild-eyed optimists, the technology
for optical switching is not yet ready.
That may change with time. The whole network is creaking with a massive
and fast-growing load of traffic today. Keeping up with the growth is a major
strain that has pushed a tremendous expansion in capacity of the fiber-optic
backbone network. On the horizon are new generations of switches, some
that route signals using optical technology instead of electronic circuits. Optical
switching technology isn’t easy; electrons are easier to manipulate because
of their electric charges. Yet the demand for more bandwidth—for bigger
switches as well as pipes—continues to escalate upward with little end in
sight. Yesterday’s fleet new modems are today’s plodding dinosaurs. Engineers
are working fast and furious to consign today’s tired old telephone and cable
systems to the same fate. Stay tuned for more thrilling episodes.