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From: padgett%tccslr.dnet@uvs1.orl.mmc.com (Padgett Peterson)
Newsgroups: comp.virus
Subject: MDC questions
Message-ID: <0007.9104081309.AA03138@ubu.cert.sei.cmu.edu>
Date: 5 Apr 91 16:42:14 GMT
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>From:    jimkirk@CORRAL.UWyo.Edu (James Kirkpatrick)

>     Questions: does anybody have a better feel for the probable security
>     of the multi-pass SNEFRU...

For discussion: a lifetime ago (when ASR-33 traffic was encrypted using the
tube-driven KY-26), I was involved with definition of such algorithms. The
impression was that for any single key multipass system, if transposition
was not used, a single-pass decryption was still possible. If transposition
was used, the same number of passes may be required to decrypt (if the
encryption is recursive, then the number is something between one and the
recursion frequency).

ANY continuous encryption method can be broken given enough horsepower (the
Intel i860 family makes it easier), the real fist question must be, "How much
is someone else willing to spend to break my system ?" and tailor your
response accordingly.

ps discontinuous cyphers are another subject but DES is continuous.