[LINK] Guidelines for Digital Repositories, Canberra, 27 July

[Kim Holburn]

On 2006 Jul 21, at 3:07 PM, Karl Auer wrote:
> On Fri, 2006-07-21 at 14:29 +1000, Markus Buchhorn wrote:
>> Regarding bit-rot, you can avoid that by reducing your compression
>> ratio a bit, by including full error-correction information  
>> (basically
>> checksums).
>
> Um, it's VERY expensive if the data is voluminous. So expensive  
> that it
> is almost always cheaper to compress the hell out of stuff, store it
> multiple times, protect it well, then keep recopying it and  
> checking it
> against itself. That is basically what biological systems do.

You can also use more stable compression systems with ideas like  
Rusty's gzip patches
<http://lists.samba.org/archive/rsync/2005-February/011602.html>
Basically you shorten the compression frames - Start from zero much  
more often.  It would make the compression less efficient probably.   
I don't think anyone has designed compression for archiving although  
I'm sure it could be done.

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Kim Holburn
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