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DES is Dead
Forwarded message:
>Date: Thu, 09 Sep 1993 10:23:00 +0000
>From: "Michael (M.J.) Wiener" <[email protected]>
>Subject: re:fw:DES is Dead
>To: [email protected]
>
>Philip,
>
>I'm pleased that my paper is getting some attention. However, there
>were a few things in your note below that concerned me.
>
>The first is minor. My last name is spelt "Wiener" - I've always been
>a little touchy about that.
>
>The second is that not only have we not built this machine, but we
>have no intention of doing so. To say that the chip is ready for
>fabrication may mislead people about our intentions. This is
>strictly a detailed paper design.
>
>Finally, I don't think that DES is dead. After about 15 years of
>public scrutiny, we can conclude that DES is a well designed cipher
>with a well understood limitation (56-bit keys). A natural
>replacement for it is triple-DES. Proclaiming the death of DES
>may lead to its being replaced with an entirely new cryptosystem
>(e.g. Skipjack).
>
>I'd appreciate it if you would send a clarification (particularly on
>the second point) to the audience that received the message below.
>
>Thanks,
>
>Mike Wiener
>
>
>>From: Philip Zimmermann <[email protected]>
>>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.
>>
>>$1 million - 3.5 hours
>>$10 miliion - 21 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. DES is dead, dead, dead.
>>
>> -prz
>>