The National Security Agency (NSA) is the cryptologic and signals intelligence agency of the United States. It is mandated to intercept and analyze foreign adversaries' communications signals, many of which are protected by codes and other complex countermeasures. The NSA collects, processes, and disseminates intelligence reports on the capabilities, intentions, and activities of foreign powers, organizations or persons.
The agency is also responsible for measures intended to protect and defend U.S. information and information systems by ensuring their availability, integrity, authentication, confidentiality, and non-repudiation. This includes providing for restoration of information systems by incorporating protection, detection, and reaction capabilities.