Parchive

Parchive (a contraction of parity archive volume set) is an erasure code system that uses a parity file format. These parity files are used to perform checksum verification, and can also repair corrupted or missing data. Parchive was originally written to solve the problem of reliably transferring files on Usenet, but it is now commonly used for protecting any kind of data from data corruption, bit rot, and accidental or malicious damage.