From: tcmay@got.net (Timothy C. May)
Date: Mon, 21 Aug 95 23:24:07 PDT
To: cypherpunks@toad.com
Subject: Re: DES & RC4-48 Challenges
Message-ID: <ac5ec2a81502100448c1@[205.199.118.202]>
MIME-Version: 1.0
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At 5:29 AM 8/22/95, hallam@w3.org wrote:

>I think we can probably do DES within two years.
>
>        Phill

I strongly doubt it, and may be willing to bet money against it happening.
(If "we" means someone or some group on this mailing list. If "we" means
the Net, I still doubt it will happen.)

If the "idea futures" and betting markets we've talked about here (which
exist) ever take off, this may be a way to make some money for someone. For
example, if someone was laying 10:1 odds that SSL would not be cracked in
1995....

And for the "do DES" bet, you need to differentiate (no pun intended)
between a chosen plaintext attack and a more general attack. The
differential cryptanalysis ("DC" gets another overload) method needs chose
plaintext to cut the search space down to 2^47 keys.

Wiener's hypothesized "million dollar DES cracker" may do the general
attack, but I doubt anyone on our mailing list will do it. That is, the
number of workstations and even supercomputers which would have to be
lashed-together would be, ballpark, about 2^16 times greater than what was
lashed-together for the SSL challenge. Maybe a factor of ten could be cut
out with increased cleverness. Maybe.

Call it a factor of "only" 6000 times harder than the SSL challenge. Hard
to imagine this happening in the next two years.

Maybe if much of the Net community was energized to run DES crackers
instead of Flying Toasters, but a hard effort to organize...for fleeting
reward.

--Tim May



---------:---------:---------:---------:---------:---------:---------:----
Timothy C. May              | Crypto Anarchy: encryption, digital money,
tcmay@got.net  408-728-0152 | anonymous networks, digital pseudonyms, zero
Corralitos, CA              | knowledge, reputations, information markets,
Higher Power: 2^756839      | black markets, collapse of governments.
"National borders are just speed bumps on the information superhighway."