Parity Archive Volume Set
The original idea behind this project was to provide a tool to apply the
data-recovery capability concepts of RAID-like systems to the posting and
recovery of multi-part archives on Usenet. We accomplished that goal. Our new
goal with version 2.0 of the specification is to improve. It extends the idea
of version 1.0 and takes the recovery process beyond the file-level barrier.
This allows for more effective protection with less recovery data, and removes
some previous limitations on the number of recoverable parts. See Par1 compared
to Par2 for a more detailed view of the differences.
Because this new approach doesn't benefit from like sized files, it drastically
extends the potiental applications of PAR. Files such as video, music, and
other data can remain in a usable format and still have recovery data
associated with them.
The technology is based on a 'Reed-Solomon Code' implementation that allows for
recovery of any 'X' real data-blocks for 'X' parity data-blocks present.
(Data-blocks referring to files OR much smaller virtual slices of files).
The key to this mission is a clean file format specification which provides all
the necessary capabilities for programs to easily verify and regenerate single
missing parts out of a set of data-blocks.
Francois Lesueur <firstname.lastname@example.org>
Peter Brian Clements <email@example.com>