The Future Is Calling
Visitors aboard a capsule on the famed London Eye ferris wheel take in panoramic views of the London skyline…or take advantage of good cell phone signal. Fiber-optic and wireless networks have created an explosion of new communications technologies in the world’s wealthiest nations, opening a “digital divide” that’s left much of the developing world behind.
Republished from the pages of National Geographic magazine
Little orange flags have sprouted along the sidewalks in Bethesda, a Maryland suburb just over the line from Washington, D.C. I have seen enough of these flags to know that they fly for the diggers. Someday soon the diggers and their backhoes and their flashing warning lights will arrive to tear up the roads and slow down traffic so they can bury something. But what?
Not far from my home I caught up with Martin J. Droney, who was running a crew of telephone company workers. Martin introduced me to the rewiring of the world. It is a world of cables buried on land and in sea beds, a world of cascading e-mail messages and a burgeoning Internet, doubling in size every year, spewing information on a scale unprecedented in history. And it is a world with a “digital divide” that separates the connected people from people so unconnected that hundreds of millions of them have never even made a phone call.
Those orange flags mark the trails of fiber-optic diggers. “Orange means communications—fiber-optic these days,” Martin said. This morning the crew was stringing, not digging. Fiber-optic cable would go overhead on utility poles for a stretch and then dive underground, joining my phone company’s eight-million-mile (12.2-million-kilometer) nationwide fiber-optic network.
The pencil-thin cable spins off its reel and flows into a black duct stiff enough to provide a pathway, whether the cable goes aerial or into the ground. It contains dozens of glass fibers, each thinner than a human hair. They are called dark fibers until they go to work, transmitting pulses of laser-generated light. Carried within the light are digitized voices, videos, computer signals, or anything else that can be made of bits. Each fiber can itself become a tiny cable capable of hauling even more signals.
The capacity of a fiber is measured in the number of bits sent per second. Megabit (a million bits) defined the capacity of early fiber-optic cables. Next came gigabit (a billion), and now comes terabit (a trillion). The latest transatlantic cable is rated at 2.4 terabits. In one second, that cable can transmit a hundred hours of digital video or 30 million phone.
Written by Thomas B. Allen