Big Brother on a budget: How Internet surveillance got so cheap

When Libyan rebels finally wrested control of the country last year away from its mercurial dictator, they discovered the Qaddafi regime had received an unusual gift from its allies: foreign firms had supplied technology that allowed security forces to track nearly all of the online activities of the country’s 100,000 Internet users. That technology, supplied by a subsidiary of the French IT firm Bull, used a technique called deep packet inspection (DPI) to capture e-mails, chat messages, and Web visits of Libyan citizens.

http://arstechnica.com/information-technology/2012/08/big-brother-meets-big-data-the-next-wave-in-net-surveillance-tech/