Keyed-Hashing Message Authentication

Keyed-Hashing Message Authentication

(messaging, cryptography)(HMAC) A mechanism for messageauthentication using cryptographic hash functions. HMACcan be used with any iterative cryptographic hash function,e.g., MD5, SHA-1, in combination with a secret shared key.The cryptographic strength of HMAC depends on the propertiesof the underlying hash function.

[RFC 2104].