Secure/Keyed Hash Function
- utilizes a cryptographic hash function and a secret cryptographic key for either:
- encryption - for message confidentiality
- HMAC - for message authenticity/integrity (HMAC is a hash-based form of MIC)
- secure hash functions generating HMACs could be used in place of “digital signatures”, but does not protect against non-repudiation (where 1 of the 2 parties that share the same key could secretly sign a message and say it was signed from the other)