Fowler-Noll-Vo hash function

Fowler-Noll-Vo, or FNV, is a non-cryptographic hash function created by Glenn Fowler, Landon Curt Noll and Kiem-Phong Vo. The idea began as reviewer comments that Fowler and Vo sent to the IEEE POSIX P1003.2 committee in 1991, and Noll improved on it in a later ballot round. The current versions are FNV-1 and FNV-1a, in 32, 64, 128, 256, 512 and 1024-bit sizes. Its main advantage is that it is very simple to implement. Hashing starts from a fixed offset basis, and for each input byte the FNV-1 version multiplies by the FNV prime and then combines the byte with exclusive or, while FNV-1a reverses those two steps. The algorithm and its reference source code were released into the public domain. FNV is not suitable for security. Python once used a modified FNV as its default string hash but replaced it with SipHash in version 3.4 to resist hash flooding denial-of-service attacks.