A Dive Into the Digital Deep
When next winter's storms subside, a specialized ship will begin a slow crossing, lowering a skinny cable into its wake along a precisely prescribed path: the shortest distance between New York and London. Owned by Summit, N.J.-based Hibernia Atlantic, the $300 million wire will bring the two financial capitals 5.2 milliseconds closer together—a boon to high-speed electronic traders.
Four thousand miles to the south, a second ship owned by a different company will move in parallel, laying a cable that will link—for the first time—Brazil and Angola. And in 2014, it will happen again, twice: from Virginia Beach to San Sebastián, Spain, and from Brazil to Nigeria. For those with memories of the global cable-laying spree that helped to drive telecommunications companies into bankruptcy in the 1990s, this will raise eyebrows. But all those cables are nearly full now. And there are other parts of the world demanding direct connections.
If the Internet is a global phenomenon, it's because there are tubes underneath the ocean. They are the fundamental medium of the global village.
The fiber-optic technology is fantastically complex and dependent on the latest materials and computing technology. Yet the basic principle of the cables is shockingly simple: Light goes in on one shore of the ocean and comes out on the other.
At each end of the cable is a landing station, around the size of a large house, often tucked away inconspicuously in a quiet seaside neighborhood. It is a lighthouse; its fundamental purpose is to illuminate the fiber-optic strands. To make the light travel enormous distances, thousands of volts of electricity are sent through the cable's copper sleeve to power repeaters, each the size and roughly the shape of a bluefin tuna. One rests on the ocean floor every 50 miles or so. Inside its pressurized case is a miniature racetrack of the element erbium, which, when energized, gooses along the photons, like a waterwheel.
It's all wonderfully poetic, an ultimate enjoining of the unfathomable mysteries of the digital world with the even more unfathomable mysteries of the oceans.
How does it all work? One company might own the fiber-optic cables, while another operates the light signals pulsing over that fiber, and a third owns (or more likely rents) the bandwidth encoded in that light. The dozen or so cables that cross the Atlantic are owned by boutique outfits like Hibernia Atlantic and Apollo; consortia of incumbent telecoms like Verizon, Sprint and Deutsche Telekom; or "backbones" with less familiar names, like Level 3 and Tata Communications. They sell passage to any company that operates its own global data network: from Qatar Telecom to Swisscom, Facebook to Goldman Sachs. Prices are perpetually falling. As the Englishmen who dominate the undersea cable industry like to say, the capacity they're selling is too often "cheap as chips."
Determining a cable's route requires navigating a maze of economics, geopolitics and topography. Specialized ships conduct surveys of the ocean bottom, plotting routes over and around underwater mountains. The paths carefully avoid major shipping lanes, to limit the risk of damage from dragging anchors. If a cable does fail, a repair ship is dispatched to lift both ends to the surface using grappling hooks and fuse the ends back together—a slow, expensive process.
Further complicating matters is the demand for low "latency," the networking term for how long it takes information to travel across the cable. Latency used to be a concern only for the telephone people, eager to avoid an unnatural delay in conversations. Now it's become an obsession of the financial industry, to serve the needs of high-speed automated trading, where computers arbitrage based on knowing the market news an extra millisecond in advance. Since the speed of light through a cable is consistent, the difference is entirely in the length of its path. Hibernia Atlantic is shaving 310 miles off the current trans-Atlantic journey, by following the shallow continental shelf (despite the heightened risk of damage).
But even in our every-millisecond-counts world, the cables' paths are often ancient, landing in or near classic port cities like Marseille, Mumbai and Mombasa. It may feel as if the Internet has created an entirely new world, but it's traced entirely upon the outlines of the old one.
—From Tubes: A Journey to the Center of the Internet by Andrew Blum. Copyright © 2012 by Andrew Blum. Published by Ecco, an imprint of HarperCollins.