There's been a lot of talk about the NSA and its data-gathering policies. The news sounds kind of scary. But you might be thinking that the NSA can't have literally every foreign and domestic call made in the U.S. That would be a crazy amount of data right? Well, yes it would be, and it kind of seems like they have it. Or at least could afford to keep it if they wanted to.
Brewster Kahle, one of the engineers behind the Internet Archive who has a good track record of not handing private user information to the feds, made the spreadsheet above to calculate roughly how much it would cost the NSA to store a year's-worth of comprehensive U.S. call data. And the number he comes out with is less than £20 million. Given that the NSA's estimated budget is about £7 billion that sounds doable. Even storing years and years of call archives could be feasible.
Kahle is obviously just looking for a ballpark figure, and notes where he is attempting to overestimate so that if anything his conclusions will be too high, not too low. His calculations indicate that the NSA would need 4,355 square feet to store the call data assuming that each American logs 300 call-minutes per month, there are two sides to each call, there are 315 million Americans, a phone call contains 8,000 bytes/second of data, a petabyte of cloud storage costs £70,000 it takes 5 kilowatts to power a petabyte, and the cost per kilowatt-hour of electricity is £0.10. Kahle's fast maths may just be an estimate, but it definitely puts things in perspective. £20 million sounds like the most money ever and a drop in the bucket all at once. [Cost to Store All US Phonecalls Made in a Year so it Could be Datamined via CNET]