1994-08-09 - Re: amateur ciphers

Header Data

From: Justin Lister <ruf@osiris.cs.uow.edu.au>
To: cypherpunks@toad.com (Cypherpunk Mailing List)
Message Hash: 62eae89f89ce40667affbfab4645bc25ed2537e9c8c3a353d0837f99c597f378
Message ID: <199408090541.AA14118@osiris.cs.uow.edu.au>
Reply To: <9408081200.AA21156@snark.imsi.com>
UTC Datetime: 1994-08-09 05:42:59 UTC
Raw Date: Mon, 8 Aug 94 22:42:59 PDT

Raw message

From: Justin Lister <ruf@osiris.cs.uow.edu.au>
Date: Mon, 8 Aug 94 22:42:59 PDT
To: cypherpunks@toad.com (Cypherpunk Mailing List)
Subject: Re: amateur ciphers
In-Reply-To: <9408081200.AA21156@snark.imsi.com>
Message-ID: <199408090541.AA14118@osiris.cs.uow.edu.au>
MIME-Version: 1.0
Content-Type: text/plain

> an118@vox.hacktic.nl says:
> > I saw an interesting post in sci.crypt last week about a particular cypher.
> > I think it ws called "The Penknife Cypher" or something along those lines.
> > I guess I have been so PGP oriented that i've sort of stuck my head in the
> > sand and ignored other possibilities regarding encryption.
> > 
> > ARE there any other good cypher's out there, suitable for e-mail usage?

> The only really reasonable symmetric key ciphers out there in
> publically described form these days are DES, 3-DES and IDEA. There
> are a couple of things that may be okay, but which aren't out in the
> public literature (RC2 and RC4), a couple of things that are likely
> okay but which we are REALLY not going to find anything out about for
> a while (Skipjack :-) and a couple of things that are promising (like
> Coppersmith's new SEAL stream cipher, which looks quite interesting
> indeed.)

I wonder on which evidence you base your assumptions ?? 
(I would assume schneiers book)

While I agree with the above ciphers, I would also add Loki and Redoc-II
both achieved good results (much better than DES) in regards to differential
cryptanalysis. Also Loki has also performed well against Linear cryptanalysis
- Matsui.
(Biham & Shamir - Differential Cryptanalysis of the Data Encryption Standard)

[ deleted info about trusting amateur ciphers ]

While Schneier's book is a very good guide, it is not very advisable to make
assumptions on the security of algorithms based on his book. One should look
at results from those performing cryptanalysis of such ciphers. Such as
biham and matsui.

> Perry

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