How the NSA is tracking people right now Documents obtained by The Washington Post indicate that the National Security Agency iscollecting billions of records a day to track the location of mobile phone users around the world. This bulk collection, performed under the NSA’s international surveillance authority,taps into the telephony links of majortelecommunications providers including some here in the United States.The NSA collects this location and travel habit data to do “target development” — to find unknown associates oftargets it already knows about. To accomplish this, the NSA compilesinformation on a vast database of devices and their locations. Most of those collected, by definition, are suspected of no wrongdoing. Officials say they do not purposely collect U.S. phone locations in bulk, but a large number are swept up “incidentally.”Using these vast location databases, the NSA applies sophisticated analytics techniques to identify what it calls co-travelers — unknown associates who might be traveling with, or meeting up with a known target.HERE IS HOW IT WORKS Target Co-traveler Read related story Target Co-traveler

SOURCE: The National Security Agency, OpenSignal and MIT Media Lab . GRAPHIC: The Washington Post.