|It's a straightforward assignment, 47.|
The National Security Agency (NSA) is a cryptologic intelligence agency of the United States Department of Defence responsible for the collection and analysis of foreign communications and foreign signals intelligence, as well as protecting U.S. government communications and information systems, which involves cryptanalysis and cryptography. 
The NSA is directed by at least a lieutenant general or vice admiral. NSA is a key component of the U.S. Intelligence Community, which is headed by the Director of National Intelligence. The Central Security Service is a co-located agency created to coordinate intelligence activities and co-operation between NSA and other U.S. military cryptanalysis agencies. The Director of the National Security Agency serves as the Commander of the United States Cyber Command and Chief of the Central Security Service. 
Role in the Hitman seriesEdit
In the book Hitman: Enemy Within the NSA are shown to maintain an amicable relationship with the Agency by passing on information on Puissance Treize.
- While having no direct impact in the games it is stated that the NSA are aware and tolerant of the ICA’s (and in turn 47’s) activities.