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Re: Wired query on Windows 2000 and DES/3DES
In message <4.3.0.20000515201050.01fab3c0@pop.webcom.com>, Declan McCullagh wri
tes:
>kbrown@mier.com wrote:
>>How did you come up with "3DES is up to 10^17 (2^(112-56)) times as
>>resistant as DES"? Is 3DES properly noted as (2^56)^3 or is it 3*(2^56)?
>
>My calculation came from _Applied Cryptography_.
>
3DES was originally spec'd as "encrypt with K1, decrypt with K2,
encrypt with K1 again". IPsec uses "encrypt with K1, decrypt with K2,
encrypt with K3", i.e., with three different keys, not two.
--Steve Bellovin