(CBS News) According to a Wall Street Journal report on Tuesday, the NSA has built a surveillance network that covers considerably more U.S. Internet communication than intelligence officials have previously disclosed publicly. The system, built by Boeing, Cisco, and Juniper Networks, draws information from telecommunications carriers that cover approximately 75 percent of all U.S. Internet traffic.
The surveillance network is designed to seek out communications that originate or end overseas or take place entirely on foreign soil, but pass through the U.S.
CBS News senior correspondent John Miller, a former deputy director of National Intelligence, explained Wednesday that the report reveals the "capability" but not the breadth of the "100-page rulebook that goes with how to use that capability."
Moreover, according to Miller, the data culled from that 75 percent of Internet communications, is so vast that the NSA is "not even putting a dent" in terms of sifting through the data, but rather collecting it so they have a record of communication and enough data to cross-check against.
"What you want to be able to do is have enough of a baseline of stuff you can search ... back more than a year. They tend to collect more so that when they have a major suspect they can say, 'Let's run this guy's communications against that haystack and see who else he is talking to."
"They're not vacuuming up 75 percent of the Internet, " Miller said, "They're talking to companies that may have access to a large percentage of it."
The NSA asks telecommunications companies -- Verizon and AT&T among them -- to filter the communications by "strong selectors" namely "key countries, key individuals" and "people who are already suspects."
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