Photograph by Jonathan Elderfield/Getty Images
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 calls across the Atlantic.
An estimated 35 million miles (56 million kilometers) of fiber lace America. But some 90 percent of the land cables are dark. Telecommunications executives, swept along by the booming Internet, vastly overestimated demand.
Martin sketched a diagram to show how my home phone's copper wire has to go through various telephone-system way stations before it reaches the kind of fiber-optic cable his crew was installing. If I make a call to, say, London, my connection might be through the Fiberoptic Link Around the Globe (FLAG), a 51,600-mile (83,042-kilometer) network that stretches from its London base to the rest of the world.
Until a few years ago my call probably would have gone to London via satellite. Now satellites orbit an Earth whose nations are increasingly tied together by submarine cables. To trace the likely path of my call, I flew to London and via a train and taxi reached a little Cornwall town named Porthcurno, at Land's End, the westernmost tip of England. Cables have been rising from the sea here since the Victorian age, when words of commerce, diplomacy, and war poured in and out of Porthcurno, the cable capital of the British Empire. Today the new 2.4-terabit Atlantic cable passes invisibly from a tranquil bay to a trench beneath a patched, gorse-lined Porthcurno lane.
Entrenched cables carry the transatlantic traffic along roads and highways to London, where it enters what is commonly called a "telehouse." Links between cable and consumer, telehouses have popped up in cities throughout the world, coddling cables with air-conditioning, protecting them with high-tech security, and connecting them to local networks. London's Telehouse Docklands is a gleaming six-story building on Coriander Avenue. Nearby streets are named Oregano, Rosemary, and Nutmeg, recalling the days when these were the spice docks.
To get in, I had to consent to a physical search and pass through tight security. Escorted by a young systems architect named Vincent Alder, I entered a building that had few people, much space, some metal boxes sprouting colored wires, and rows of empty racks waiting for more "magic boxes," as Vincent calls them—the servers, routers, and other equipment needed for the Internet. "It's like watching a supernova," Vincent said, his hands sweeping through the emptiness. "No one knows how it's going to end."
The first wiring of the world began in 1850, only six years after Samuel Morse demonstrated the reality of telegraphy. British engineers made a copper-wire cable, insulated it with gutta-percha (a rubberlike Malayan tree sap), and laid it across the English Channel.
Soon came a cable across the Atlantic. On August 16, 1858, Queen Victoria sent a hundred-word message to President James Buchanan. Some of the royal words reached Washington that day; the rest came through on the 17th. Agonizingly slow and chronically unreliable, the cable went dead after three weeks.
The problem was the behavior of electricity in cables. Convinced that they had found the solution, engineers tried again, this time with the world's largest ship, the Great Eastern. In July 1865 she set out from England with a crew of 500, a dozen oxen for hauling, a cow for fresh milk, a herd of pigs for bacon—and a thickly insulated 2,800-mile (4,506-kilometer) cable that weighed 5,000 tons (4,536 metric tons). They had almost finished laying it when the cable snapped. The next year they succeeded.
Cable laying continued through the 19th century and into the 20th. Words were humming along at more than 200 a minute, compared with 12 a minute in 1866. But cable met competition when wireless telegraphs, in 1901, and commercial telephone calls, in 1927, began crackling across the Atlantic on radio waves. Not until 1956 did a telephone cable span the Atlantic. Then in 1965 the first Early Bird Satellite went into orbit, and again cable became a has-been.
But by the mid-1990s, thanks to fiber optics, cable was making a comeback, carrying most telephone calls between the United States and Europe, Japan, and Australia. Pulsing with Internet data packets, cables connect more than 80 nations, carrying far more telephone calls than satellites or mobile phones. But those mobile phones and satellites are bridging the digital divide, using wireless networks as a way to connect the unconnected.
Maps of the rewired world vividly show the divide. One wide swath, from North America to Europe, is dense with communications, while vast areas, such as the African and South American continents, are blank. When the connected world reaches those blank spots, the people in them begin to prosper, says Vinod Thomas, vice president of the World Bank Institute, created in 1999 to serve as a knowledge bank for developing countries. He handed me a chart that compared South Korea and Ghana, which both had about the same level of poverty in 1962. Then, while the average income level stagnated in Ghana, South Korea's income started to soar, aided by that nation's investment in communications.
"Distance learning," through satellite-beamed videoconferences, is also bridging the digital divide. The African Virtual University, for example, has a faculty of North American and European professors whose lectures are televised and sent to students in 16 African countries. The virtual university also offers computer courses to African teachers lucky enough to have computers in their classrooms.
I did a little distance learning myself in a World Bank Institute videoconference classroom. Through its satellite network the institute connects learning centers in some 30 countries. Discussions range from health care to preventing corruption.
I looked at myself projected on a large screen, along with squares occupied by images of African entrepreneurs who run computer centers in Senegal, Cote d'Ivoire, and Ghana. The centers serve as paths to the connected world's information highway. People get their first look at the Internet, send their first e-mails (Gregory looks for lost relatives), speak up in chat rooms ("…I didn't come here to bandy words with you"), and learn how to sign up for distance-learning university courses.
Many countries, such as China and Brazil, avoided the lengthy and expensive process of stringing more nationwide telephone lines by leapfrogging over copper wire and setting up cellular phone systems. Shanghai, for instance, with a population of 17 million, has more than 3 million mobile phone users.
It took a hundred years to connect a billion people by wire. It has taken only ten years to connect the next billion people.
The Internet gave cable a new set of customers. A round-trip satellite signal takes a quarter of a second, an endurable delay during a phone conversation. But for the connected on the Internet, delay is intolerable and time is measured in nanoseconds. Internet facts and foibles move along fiber-optic cables at nearly the speed of light. The Internet seems to be neither here nor there. In the rewired world, as hackers say, the world is one big wire, and distance is dead.
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