Question

What hashing method uses fixed-length string of bits but also uses a shared secret key to add randomness and only the sender and receiver are aware?

Answer 1

The hashing method that uses a fixed-length string of bits and a shared secret key to add randomness is called HMAC (Hash-based Message Authentication Code).

Step-by-step explanation:

The hashing method that uses a fixed-length string of bits and a shared secret key to add randomness, where only the sender and receiver are aware, is called HMAC (Hash-based Message Authentication Code).

HMAC is a type of hash function that combines a cryptographic hash function with a secret key to provide data integrity and authenticity.

For example, in network communication, HMAC can be used to verify the integrity of data packets by generating a unique hash using the shared secret key. This ensures that the data has not been tampered with during transmission and can only be validated by the sender and receiver who possess the secret key.