Can CRC32 Be Used As A Hash Function?
Answer : CRC32 works very well as a hash algorithm. The whole point of a CRC is to hash a stream of bytes with as few collisions as possible. That said, there are a few points to consider: CRC's are not secure. For secure hashing you need a much more computationally expensive algorithm. For a simple bucket hasher, security is usually a non-issue. Different CRC flavors exist with different properties. Make sure you use the right algorithm, e.g. with hash polynomial 0x11EDC6F41 (CRC32C) which is the optimal general purpose choice. As a hashing speed/quality trade-off, the x86 CRC32 instruction is tough to beat. However, this instruction doesn't exist in older CPU's so beware of portability problems. ---- EDIT ---- Mark Adler provided a link to a useful article for hash evaluation by Bret Mulvey. Using the source code provided in the article, I ran the "bucket test" for both CRC32C and Jenkins96. These tables show the probability that a tru...