From mboxrd@z Thu Jan  1 00:00:00 1970
From: Piergiorgio Sartor <piergiorgio.sartor@nexgo.de>
Subject: Re: Triple-parity raid6
Date: Sat, 11 Jun 2011 12:13:12 +0200
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[snip]
> Of course, all this assume that my maths is correct !

I would suggest to check out the Reed-Solomon thing
in the more friendly form of Vandermonde matrix.

It will be completely clear how to generate k parity
set with n data set (disk), so that n+k < 258 for the
GF(256) space.

It will also be much more clear how to re-construct
the data set in case of erasure (known data lost).

You can have a look, for reference, at:

http://lsirwww.epfl.ch/wdas2004/Presentations/manasse.ppt

If you search for something like "Reed Solomon Vandermonde"
you'll find even more information.

Hope this helps.

bye,

-- 

piergiorgio