Revelations that the National Security Administration collects and stores information from U.S. internet and telephone companies has catapulted questions about privacy, security, and freedom into the national spotlight.
But the NSA's PRISM program—which the Guardian says allows "direct access to the systems of Google, Facebook, Apple and other US internet giants"—also raises a more fundamental question: Where will all of that data go?
The answer is most likely a range of data centers, which are massive facilities designed to store data without ever losing power. The NSA is currently finishing construction on its Utah Data Center, a new $1.2 billion storage facility near Salt Lake City. When it's finished, the data center will be able to hold and process five zettabytes of data, according to NPR.
That simple fact raises many questions. For answers, we turned to the Internet and human experts.
Never heard of a zettabyte?
You're not alone. Many of us still think in terms of gigabytes and megabytes, which are the units most commonly found in our own personal computers.
A gigabyte, for example, contains one billion bytes, or about seven minutes of HDTV video. (You can think of a byte as the amount of space needed to store one typed letter on a keyboard.) An average DVD holds somewhere in the ballpark of 4.7 gigabytes.
One zettabyte (ZB), meanwhile, is 10 to the power of 21 bytes—or the amount of data that could fill 250 billion DVDs. So far, no storage system in the world contains this much data, but Cisco estimates that the collective Internet will start sending zettabyte-levels of data by 2015.
What's that mean? You can think of it this way: In two years, the equivalent of more than five years' worth of video will be transmitted across the Internet every single second of every single day.
In terms of scaling, "if the 11 [ounce] coffee on your desk equals one gigabyte, a zettabyte would have the same volume as the Great Wall of China," according to a graphic by Cisco. (The term zetta comes from the French number sept, which means seven. The seventh power of 1,000 is a zetta.)
Why does the NSA need so much space?
According to Wired magazine, the Utah Data Center will "intercept, decipher, analyze, and store vast swaths of the world's communications as they zap down from satellites and zip through the underground and undersea cables of international, foreign, and domestic networks."
That's a lot of data—which requires a lot of storage.
What about the environmental costs?
All of that storage space requires a lot of electricity. The NSA's new center requires 65 megawatts of electricity per year, which is equivalent to the power for 65,000 homes. To cool all of that down, more than 1.5 million gallons of water will need to be pumped through the facility on a daily basis, according to the NPR report.
Jon Koomey, an energy futurist and research fellow at Stanford University, explains that data centers around the world use a little more than one percent of the world's total electricity.
"In the aggregate it's not a huge number," he says. "But individually, each of these data centers can use tens of megawatts, which are equivalent to a small city or industrial plant."
That's why so many data centers are set up in places where electricity is cheaper, he says.
"That's one reason why you see data centers springing up in places like the Northwest and North Carolina," he says. "Having cheap electricity is a key driver."
And what about the climate?
A dry, cool climate is also key.
"A desert climate is quite helpful," Koomey says. "You can use the outside air when it's cold to cool the data center during the day." (Related: "National Snow and Ice Data Center Gets a Cool Makeover.")
This helps lower overall electrical costs, he says. And, he notes, companies can use data centers to crunch numbers to help other parts of their business run more efficiently—which can actually save money.
"When you step into the cloud and replace atoms with bytes, you don't have to manufacture chips anymore - and that means big savings," he says.
So what happens when the NSA runs out of space?
The new NSA facility in Utah could potentially hold the equivalent of data from about 300 billion iPhones. But what happens if the NSA runs out of room?
It's likely it won't ... because the agency is also building another data farm at Fort Meade, Maryland. But if all of the zettabytes fill up, the agency will have to resort to using yottabytes. A yottabyte, naturally, is 1,000 zettabytes, or one septillion bytes.
A yottabyte stored on terabytes would require a million data centers, which would fill Delaware and Rhode Island combined, reports Gizmodo.
And if it runs out of yottabytes?
Then there's a problem, in part because there's no official prefix after "yotta." Some have suggested the prefix bronto-, as in brontosaurus. An online petition in 2010 advocated for the prefix hella-, as in hella big.
But nothing official has been determined. Which means the playing field is wide—or should we say yotta-size—open!
Have a suggestion for the next prefix? Let us know in the comments.
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