Hashrelated

Hashrelated is an informal term used to describe anything pertaining to hash functions and their properties, implementations, or applications. In cryptography, hash-related topics typically refer to cryptographic hash functions, which map inputs of arbitrary length to fixed-length digests, with properties of determinism, preimage resistance, second-preimage resistance, and collision resistance. Non-cryptographic hash functions used for data structures and indexing are also hash-related, though they may not guarantee cryptographic security.

Applications of hash-related concepts include data integrity verification, digital signatures, password storage with computed hashes, and blockchain content addressing. In blockchains, hash-related constructions such as Merkle trees rely on hashes to prove inclusion efficiently, while mining depends on hash difficulty as a measure of computational effort.

Common concerns in hash-related practice include the risk of collisions and preimage attacks, which have led to the deprecation of weak algorithms (for example MD5 and SHA-1) in favor of stronger standards like SHA-256, SHA-3, or BLAKE2. Password storage often uses salted and iterated hashing to resist rainbow table attacks, along with additional protections such as peppering.

Best practices in hash-related work emphasize using well-vetted cryptographic hash functions, implementing salting and key stretching for password hashing, avoiding hash-only schemes for sensitive data, and employing cryptographic constructions such as HMAC, key derivation functions, and dedicated password hashing schemes (e.g., Argon2, scrypt, PBKDF2).

See also: hash function, cryptographic hash function, collision resistance, preimage resistance, data integrity, Merkle tree, blockchain, password hashing.