Message Authentication Code

A code used for integrity checks.

$$\text{MAC}=\text{Hash}(M|s)$$

• $M$ is the message
• $\text{Hash}$ is the hash funciton
• $s$ is the secret key

Properties

• Non-Repudiation is not given
• Integrity

Types

• Secret Prefix MAC
• Secret Suffix MAC
• GMAC
• CMAC
• HMAC
• UMAC
• Poly1305