From: "B. Schneier" <bs208@newton.cam.ac.uk>
Date: Fri, 8 Mar 1996 02:27:21 +0800
To: cypherpunks@toad.com
Subject: Re: TET cryptosystem
In-Reply-To: <199603071529.HAA04759@well.com>
Message-ID: <199603071719.MAA06009@gibbs.newton.cam.ac.uk>
MIME-Version: 1.0
Content-Type: text/plain


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> Teledyne (TET) is out marketing a "new" crypto system as a
> competitor against DES and what TET calls "linear" cryptosystems. 
> They are claiming a non-linear approach in which (as best I can
> tell) they are permuting the s-boxes and using 4 bit/16 entry
> substitution tables.
> 
> They are also asserting that these "key generated substitution
> tables and inter-round permutations" are supported by "nonlinear
> orthomorphic mappings generated from arbitrary key" (and that this
> is patented) and "row-complete Latin Squares generated from an
> arbitrary key" (and that this is also patented).
> 
> The claimed benefits include being invulnerable to differential and
> "linear" cryptanalysis, no linear key/data interaction to hide,
> that this results in the tables and permutations being
> "transient/secret," and that fewer rounds are needed (fewer than
> what, I don't know) to attain "resistance to cryptanalysis."

This explanation is so laced with nonsensical buzzwords that the algorithm
is probably absolute nonsense.  I can't tell you (because of NDAs) how
many times I've seen proprietary algorithms that make all sorts of
grandeose claims of security and are actually terrible.

Bruce
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* Bruce Schneier
* Counterpane Systems         For a good prime, call 391581 * 2^216193 - 1
* schneier@counterpane.com
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