HMAC keys are symmetric keys. They are variable-length keys (80-2024 bits). They can only be used to generate and verify MACs using the FIPS-198 algorithm.

• Operational keys will be encrypted under the AES master key.
• HMAC keys may be imported and exported under an RSA key.
• HMAC keys will be stored in the CKDS. The AES master key must be active.