The Terremark facility is among the most wired sites in the world. It is one of dozens of Internet exchanges in the U.S., located mostly on the coasts, that gather the undersea cables and disperse them over land across the country. They are the unmissable links in America’s--and the world’s--telecom network. Some 90 percent of the Internet traffic between North America and Latin America goes through Terremark in Miami, for example, and according to TeleGeography, that traffic grew 112 percent from mid-2007 to mid-2008.
The cables that enter Terremark from the Atlantic rise up through the floor at various spots like bouquets of plumbing. The main cables splay out along metal trellises to the 160 or so clients that have servers onsite.
Eventually, the cables all return to a glass-enclosed, spotlessly clean space known as the "meet-point room." The meet-point rooms--there are at least two of them on each floor of the building--are the gateways to the Internet. They are where the cables from individual carriers are patched into the land-based cable network that radiates out from Terremark, connecting service providers with other exchange points, and from there connecting to individual homes and businesses.
Technicians are in the building at all times. They take care of the routine maintenance--tightening a loose connection here, rewiring a patch panel there--needed to keep the Internet running. Even in a hurricane, the building is staffed. Twenty-four hours before a storm hits, all essential personnel--generally, a team of 30 technicians--are already inside. They don’t come out until the hurricane has passed. And everything is monitored from a NASA-like network-operation center elsewhere in the building.Terremark, like any Internet exchange, is vital to the network. That’s why the walls are made of seven-inch, steel-reinforced concrete that can withstand the 155mph winds of a Category 5 hurricane. That’s why environmental control is fanatically precise, keeping condensation off the circuits and the thousands of servers cool. That’s why on top of paying $630,000 a month for electricity, the building also maintains its own bank of diesel generators as a backup. And that’s why, if any disaster were to strike Miami, restoring Terremark’s power would have priority along with hospitals and the police. In short, it would be very bad if something happened at Terremark. "If a service provider goes down, it’s terrible," says Derrick Cardenas, Terremark’s regional vice president of commercial sales. "If we go down, it’s global."
Terremark and the other exchanges scattered across the country (Chicago, New York and Los Angeles are just a few of the other locations) are so vital because the Internet is a "scale-free network." In a scale-free network, connections are not randomly or evenly distributed. Some points have relatively few connections to other points (a single server in the basement of a small business, for example), and some points—known as hubs—have a relatively huge number of connections to other points (Terremark). This ratio of very connected hubs to less-connected points remains roughly the same no matter the network’s size (hence "scale-free"). The hubs are both a strength and a weakness. If one hub fails, the others can take up the slack. If several hubs go out of service, however, whole sections of the network can become isolated.
"The main feature of a scale-free network is that a few highly connected hubs hold the network together," says Albert-Laszlo Barabasi, director of the Center for Complex Network Research at Northeastern University, who did some of the earliest studies of scale-free networks. "If you remove one hub, the network will not fall apart; the smaller hubs will maintain it. But if you [simultaneously] knock down a sufficient number of hubs, there will be quite a lot of damage."single page
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