Laying undersea cable systems is a monumental process. After surveying landing sites, studying seabed geology, and assessing risks, engineers plot a route. A company like Corning delivers strands of fiber-optic glass to a manufacturer say, Tyco Telecommunications which encases the fiber in metal. Then gigantic spools of cable, repeaters that transmit signals long distances, and other gear are loaded on cable-laying vessels. For months, the ships lower the cables thousands of feet to the seabed. In congested spots, engineers use robots to dig trenches for the cable that protect it from wayward anchors and fishing nets. Then crews haul the cable ends above water and connect them to land-based stations.
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Engineering experts say the Taiwan incident should persuade all operators to do more to prepare for quakes. It’s not good enough if you have a variety of routes but then bring them into shore at the same location–especially if, as in the Taiwan case, they’re crossing a fault line right there.
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But there’s another lesson: The global telecom network really is quite resilient, even in the face of such a crippling blow. Within 12 hours of the undersea rock slides, at least partial service had been restored to most of the affected networks. This was done by rerouting traffic via land and sea through Europe to the U.S.