Quote:
The NSA and Defense Department have embraced open source security software to guard their networks. Columbia, Md.-based Sourcefire, which developed network security software from the open source community, has a number of government contracts to protect sensitive data. The NSA declined to comment on whether it would use a product such as Exponential's, saying it doesn't discuss how its operating system works.

http://www.linuxinsider.com/rsstory/62113.html?welcome=1205717213