How the NSA Exploits VPN and VoIP Traffic

These four slides, released yesterday, describe one process the NSA has for eavesdropping on VPN and VoIP traffic. There's a lot of information on these slides, though it's a veritable sea of code names. No details as to how the NSA decrypts those ESP -- "Encapsulating Security Payload" -- packets, although there are some clues in the form of code names in the slides.