The United States Government has published guidelines for "NSA Suite B Cryptography" dated July, 2005, which defines cryptographic algorithm policy for national security applications. This document specifies the conventions for using Suite B cryptography in IP Security (IPsec).

This document specifies two encryption types and two corresponding checksum types for Kerberos 5. The new types use AES in CTS mode (CBC mode with ciphertext stealing) for confidentiality and HMAC with a SHA-2 hash for integrity.