NSA cryptography

The vast majority of the National Security Agency's work on encryption is classified, but from time to time NSA participates in standards processes or otherwise publishes information about its cryptographic algorithms. The NSA has categorized encryption items into four product types, and algorithms into two suites. The following is a brief and incomplete summary of public knowledge about NSA algorithms and protocols.

Type 1 Product
A Type 1 Product refers to an NSA endorsed classified or controlled cryptographic item for classified or sensitive U.S. government information, including cryptographic equipment, assembly or component classified or certified by NSA for encrypting and decrypting classified and sensitive national security information when appropriately keyed.

Type 2 Product
A Type 2 Product refers to an NSA endorsed unclassified cryptographic equipment, assemblies or components for sensitive but unclassified U.S. government information.

Type 3 Product
Unclassified cryptographic equipment, assembly, or component used, when appropriately keyed, for encrypting or decrypting unclassified sensitive U.S. Government or commercial information, and to protect systems requiring protection mechanisms consistent with standard commercial practices. A Type 3 Algorithm refers to NIST endorsed algorithms, registered and FIPS published, for sensitive but unclassified U.S. government and commercial information.

Type 4 Product
A Type 4 Algorithm refers to algorithms that are registered by the NIST but are not FIPS published. Unevaluated commercial cryptographic equipment, assemblies, or components that neither NSA nor NIST certify for any Government usage.

Suite A
A set of NSA unpublished algorithms that is intended for highly sensitive communication and critical authentication systems.

Suite B
A set of NSA endorsed cryptographic algorithms for use as an interoperable cryptographic base for both unclassified information and most classified information. Suite B was announced on 16 February 2005.

Suite C
A set of NSA endorsed cryptographic algorithms for use as an interoperable cryptographic base for both unclassified information and most classified information. Suite C is currently awaiting approval.