From: Cypherpunks Maintenance Account <cpunks@www.video-collage.com>
Date: Thu, 28 Aug 1997 08:56:32 +0800
To: cypherpunks@www.video-collage.com
Subject: Re:  CAST key size (fwd)
Message-ID: <199708280047.UAA19296@www.video-collage.com>
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----- Forwarded message from Peter Gutmann -----

>From cpunks  Mon Aug 25 08:03:32 1997
From: pgut001@cs.auckland.ac.nz (Peter Gutmann)
To: hvdl@sequent.com
Subject: Re:  CAST key size
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Date: Mon, 25 Aug 1997 23:39:58 (NZST)
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>Just a quick question on the keysize of the CAST algorithm. According to
>the bible of Bruce,  CAST uses a 64 bit keysize, while  in the manual of
>PGP 5.0 (page 89), Phill states that CAST uses a 128 bit keysize...
>
>Am I missing something?
 
"CAST" isn't a particular algorithm, but a design process for creating 
algorithms.  The particular CAST instantiation used in PGP 5 is either 
CAST-128 or CAST5, depending on who you ask.  Other versions of CAST abound, 
including an earlier one used by MS for unknown purposes which had a 64-bit 
key, probably the one Bruce is referring to.
 
Peter.

----- End of forwarded message from Peter Gutmann -----