Cryptography
SHA-3
Also known as: Keccak, FIPS 202
Definition
A family of hash functions based on the Keccak sponge construction, standardized by NIST as a structurally different alternative to SHA-2.
Examples
- Ethereum uses Keccak-256 (a SHA-3 variant) for addresses and Merkle trees.
- SHAKE128 is used as the extendable-output function in CRYSTALS-Dilithium.
Related terms
Cryptographic Hash Function
A deterministic one-way function that maps arbitrary-length input to a fixed-length digest, designed to be collision-, preimage-, and second-preimage-resistant.
SHA-256
A 256-bit cryptographic hash function from the SHA-2 family, widely used for digital signatures, TLS, blockchains, and integrity verification.
BLAKE2
A fast, modern cryptographic hash function specified in RFC 7693, offering security comparable to SHA-3 with significantly higher performance in software.
HMAC
A keyed Message Authentication Code construction built on top of a cryptographic hash function, defined in RFC 2104 and FIPS 198-1.
Post-Quantum Cryptography
Classical cryptographic algorithms designed to remain secure against attacks by both classical and large-scale quantum computers.
Digital Signature
A public-key cryptographic mechanism that proves the authenticity, integrity and non-repudiation of a message or document.