A posting from Information Week in there Security Storage section:
NSA investigators now “know how many documents he downloaded and what server he took them from,” a government official — speaking on condition of anonymity — told the paper.
In general, the use of removable USB storage devices is prohibited inside the agency. “Of course, there are always exceptions” to that rule, said the official. “There are people who need to use a thumb drive and they have special permission. But when you use one, people always look at you funny.”
One job role that would require using removable storage, however, would be that of IT or systems administrator, which was Snowden’s job at the NSA, although he was a contractor employed by Booz Allen Hamilton.
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