Parity Volume Set
Parity Volume Set (also known as parity archive or parchive) is a file format for storing redundant data for one or more input files. These data can be used to repair the input files if they get damaged. The error correction is based on the Reed-Solomon algorithm. Three versions of the format exist: Par1, Par2 and Par3. The Par3 format never made it beyond the proposal stage, but it is used by the MultiPar tool.
A Par1 file starts with the byte sequence
50 41 52 00 00 00 00 00, which corresponds to the ASCII text string
PAR, followed by 5 nul bytes. A Par2 file starts with bytes
50 41 52 32 00 50 4B 54, which corresponds to ASCII text string
PAR2, followed by a null byte and the text string
PKT. Finally, a Par3 file usse the 4-byte sequence
50 41 33 00 (
PA3 followed by a null byte).
- Parity Volume Set Specification v1.0
- Parity Volume Set Specification 2.0
- proposal for Parchive Specification 3.0