Understanding Cryptographic Hash Functions: Key Security Properties

What is a cryptographic hash function and what are its three key security properties?

Final answer: A cryptographic hash function is a mathematical algorithm that produces a fixed-size string of characters unique to the input. The three key security properties of a cryptographic hash function are collision resistance, preimage resistance, and second preimage resistance.

Explanation:

What is a cryptographic hash function?

A cryptographic hash function is a mathematical algorithm that takes an input (or message) and produces a fixed-size string of characters, which is typically a hash value or hash code. This hash code is unique to the input, meaning that even a small change in the input will produce a completely different hash code.

What are the three key security properties of a cryptographic hash function?

Collision Resistance: A good hash function should make it extremely difficult to find two different inputs that produce the same hash code.

Preimage Resistance: It should be computationally infeasible to determine the original input (or message) from its hash code.

Second Preimage Resistance: Given an input (or message), it should be computationally infeasible to find a different input that produces the same hash code.