From: "L. Detweiler" <ld231782@longs.lance.colostate.edu>
Date: Thu, 9 Sep 93 01:17:12 PDT
To: cypherpunks@toad.com
Subject: PRZ: ``is DES dead? ''
Message-ID: <9309090812.AA01090@longs.lance.colostate.edu>
MIME-Version: 1.0
Content-Type: text/plain


seen on info.pem-dev, headers deleted

===cut=here===

From: Philip Zimmermann <prz@columbine.cgd.ucar.EDU>
To: ratinox@ccs.neu.edu
Subject: Re: DES Key Search Paper (fwd)

Michael Weiner presented a paper at Crypto93 that describes a fast DES
key search engine that uses a special inside-out DES chip that he designed.
This chip takes a single plaintext/ciphertext pair and quickly tries 
DES keys until it finds one that produces the given ciphertext from the
given plaintext.  Weiner can get these chips made for $10.50 each in quantity,
and can build a special machine with 57000 of these chips for $1 million.
This machine can exhaust the DES key space in 7 hours, finding a key
in 3.5 hours on the average.  He works for Bell Northern Research in 
Ottawa, and says they have not actually built this machine, but he has
the chip fully designed and ready for fabrication.  

This is a stunning breakthrough in the realization of practical DES
cracking.  BTW-- note that PEM uses straight 56-bit DES.

-prz

Forwarded message:
>From prz Wed Sep  1 14:11:48 1993
>Message-Id: <9309012010.AA10083@columbine.cgd.ucar.EDU>
>Subject: Re: DES Key Search Paper
>To: wiener@bnr.ca (Michael)
>Date: Wed, 1 Sep 93 14:10:18 MDT
>From: Philip Zimmermann <prz@columbine.cgd.ucar.EDU>
>Cc: prz (Philip Zimmermann)
>In-Reply-To: <"15836 Wed Sep  1 12:14:00 1993"@bnr.ca>; from "Michael"
at Aug 31, 93 11:32 am
>X-Mailer: ELM [version 2.3 PL0]
>
>Thanks, Michael.  Your paper was the most important paper presented 
>at Crypto93, in my opinion.  It drove a wooden stake thru DES's heart.
>
>$1 million     - 3.5 hours
>$10 miliion    - 20 minutes
>$100 million   - 2 minutes
>
>It is not plausible to me that NSA's budget for examining DES-encrypted
>traffic is less than $100 million.   Two minutes.  Damn.  Two fucking
>minutes.  DES is dead, dead, dead.
>
>Regards,
>Philip
>