The NSA collects almost 5 billion international cellphone records a day, feeding a massive location database, according to documents leaked by former NSA contractor Edward Snowden.
According to The Washington Post, top-secret documents and interviews with high level security officials confirmed the existence of a US-run database that tracks the locations of hundreds of millions of electronic devices around the world.
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The tracking, intended to capture travel or congregation that may indicate terrorist activity, appears to be carried out by means of taps on the communication conduits that carry international cellphone traffic, wrote The New York Times on Wednesday.
All these records combine to create a database of enormous size that has real-time information on the locations of thousands of people around the world, which is then processed by a shadowy secret program known as "CO-TRAVELER," according to ZDNet.
The relationships and habits of these individuals under surveillance can then be tracked and analyzed. Although the surveillance isn't intended to target Americans, it appears that the locations and records of tens of millions Americans who travel abroad have been "inadvertently" gathered, according to the Associated Press.
The potential implications of this massive amount of information, collected by the US government, will likely add to the international privacy concerns raised by the initial May 2013 NSA revelations.
“Many shared databases, such as those used for roaming, are available in their complete form to any carrier who requires access to any part of it,” Matt Blaze, a University of Pennsylvania computer and information science professor, told the Washington Post.
“This ‘flat’ trust model means that a surprisingly large number of entities have access to data about customers that they never actually do business with, and an intelligence agency — hostile or friendly — can get ‘one-stop shopping’ to an expansive range of subscriber data just by compromising a few carriers.”