In addition to monitoring various types of digital communication, the National Security Agency (NSA) is also collecting large amounts of data on cellphone location.
Based on information received from former NSA contractor Edward Snowden, the Washington Post reveals that the agency collects as many as 5 billion cellphone location records each day, as it tries to identify certain mobile behavior patterns that would match individuals with malicious intentions, as well as to single out relationships between targets and collaborators.
But the NSA isn’t targeting specific individuals in this broad data mining operation, as it simply collects all available location data from many mobile operators around the world in order to analyze it and look for strange behavior. While spying on location data as collected by carriers around the world, the NSA also “incidentally” collects data on American citizens that travel to other countries and who should be protected by the Fourth Amendment. However, from what NSA officials and lawyers were able to tell the publication, the data collection on American citizens isn’t intentional, only a collateral effect of the large net it has cast on location tracking.
Because every mobile device has to connect to a carrier tower at all times in order to allow the user to make calls, send messages and browse the web (in case of smartphones), this means that virtually any mobile device that has a cellular component is being spied upon. By collecting all this data – which may top 27 terabytes, or “more than double the text content of the Library of Congress’s print collection” – the NSA can find relevant targets, retrace their steps and monitor potential suspect relationship with other potential targets that they frequently encounter.
While managing such an amount of data isn’t an easy task, the agency is able to look for relevant information. The NSA uses complex analytics tools to monitor targets, to determine their likely travel time and possible intersections:
The most basic analytic tools map the date, time, and location of cellphones to look for patterns or significant moments of overlap. Other tools compute speed and trajectory for large numbers of mobile devices, overlaying the electronic data on transportation maps to compute the likely travel time and determine which devices might have intersected.
It’s unclear whether mobile operators are aware of this issue that affects the privacy of millions of mobile device owners – “the NSA’s database includes information about the location of at least hundreds of millions of devices” – but it looks like the NSA isn’t having too much trouble getting its data. According to one official, the NSA is getting its location data from around the world, “by tapping into the cables that connect mobile networks globally.”
While communication methods between mobile devices on a network can be protected through encryption against the NSA’s snooping, location data isn’t exactly something that can be as easily protected. One way of disappearing from the net is to avoid using mobile devices altogether, and only use them whenever necessary. But then, that kind of behavior – turning on and off a device at certain intervals, or switching between disposable cellphones – would only trigger the NSA’s curiosity as to why the user is acting in such a manner. Because usually, unsuspecting mobile users would use their mobile devices without worrying about having their location tracked at all times.
The following infographic, provided by the Washington Post, explains how the entire location data mining process takes place, and how the agency follows potential targets and their potential relationships with others: