The Central Security Service (CSS) is an agency of the The United States Department of Defense, which was established in 1972 to integrate the National Security Agency (NSA) and the Service Cryptologic Components (SCC) of the United States Armed Forces in the field of signals intelligence, cryptology, and information assurance at the tactical level. In 2002, the CSS had approximately 25,000 uniformed members. It is part of the United States Intelligence Community. [1]

Sources

[1] https://en.wikipedia.org/wiki/Central_Security_Service