Which one of the following are characteristics of a hash function? (Choose two)

Correct answers: One-way, Fixed length output https://en.wikipedia.org/wiki/Cryptographic_hash_function A cryptographic hash function is a mathematical algorithm that maps data of arbitrary size (often called the "message") to a bit array of a fixed size (the "hash value", "hash", or "message digest"). It is a one-way function, that is, a function which is practically infeasible to invert. Incorrect answers: Symmetric. Cryptographic algorithms can be categorized into three classes: Hash functions, Symmetric and Asymmetric algorithms. Differences: purpose and main fields of application. Requires a key. Well, technically, this is the correct answer. But in the hash-function, “key” is input data. Fast. Fast or slow is a subjective characteristic, there are many different algorithms, and here it is impossible to say this unambiguously like "Symmetric encryption is generally faster than asymmetric encryption."