WIRED published a long piece on Edward Snowden
today (worth a read on its own), and simultaneously broke news of "MonsterMind," an NSA program to monitor all network traffic and detect attacks, responding with a counterattack automatically. From the article: Although details of the program are scant, Snowden tells WIRED in an extensive interview with James Bamford that algorithms would scour massive repositories of metadata and analyze it to differentiate normal network traffic from anomalous or malicious traffic. Armed with this knowledge, the NSA could instantly and autonomously identify, and block, a foreign threat. More than this, though, Snowden suggests MonsterMind could one day be designed to return fire — automatically, without human intervention...
Snowden raised two issues with the program: the source of an attack could be spoofed to trick the U.S. into attacking an innocent third party, and the violation of the fourth amendment since the NSA would effectively need to monitor all domestic network traffic for the program to work. Also in Bamford's interview are allegations that the NSA knocked Syria offline in 2012
after an attempt to install intercept software on an edge router ended with the router being bricked.