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List:       linux-crypto
Subject:    Re: a question about ciphers
From:       Jerome Etienne <jme () off ! net>
Date:       2001-12-13 16:02:06
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On Thu, Dec 13, 2001 at 04:19:18PM +0100, Marc Mutz wrote:
> > > blowfish is fast and has quite a long track record. I'd use it if
> > > it wasn't for the 64bit blocksize. In fact, I do use it ;-)
> > > The blocksize isn't an issue if you enrypt only modest volumes of
> > > data under a single key (like you should!) Several hundred MB are
> > > OK. But don't go beyond 2 or 3 GB.
> >
> > what are the detail of the problem with blowfish beyond 2 or 3GB ?
> 
> Birthday attack. Equal ciphertexts are being generated. Actually, the 
> boundary is 32G, but it's best to stay away from it.

suppose you are the attacker and get data encrypted with a block cipher,
two or more cipher texts block are equal, which information did get 
from it ?
-
Linux-crypto:  cryptography in and on the Linux system
Archive:       http://mail.nl.linux.org/linux-crypto/

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