Adler-32

Adler-32 is a checksum algorithm created by Mark Adler in 1995 as a modification of the Fletcher checksum. It computes two 16-bit checksums over a block of data and combines them into a single 32-bit value. Adler-32 trades reliability for speed compared to a cyclic redundancy check of equivalent length: it is faster than CRC-32 on many platforms, but its checksum can be forged easily and gives poor coverage of the 32 available bits on short messages, so it is unsuitable for detecting deliberate tampering. It is best suited to catching accidental data corruption, which is how it is used inside the zlib compression library, also written by Adler, and in a rolling-checksum form inside the rsync file synchronization utility. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/