Which statement is a feature of HMAC?
- HMAC uses a secret key that is only known to the sender and defeats man-in-the-middle attacks.
- HMAC uses protocols such as SSL or TLS to provide session layer confidentiality.
- HMAC uses a secret key as input to the hash function, adding authentication to integrity assurance.
- HMAC is based on the RSA hash function.
Explanation: A keyed-hash message authentication code (HMAC or KHMAC) is a type of message authentication code (MAC). HMACs use an additional secret key as input to the hash function, adding authentication to data integrity assurance.