Re: The Cost of Snakeoil (was Re: John Gilmore and the Great Internet Snake Drive)

Kriston J. Rehberg (kriston@ibm.net)
Tue, 21 Jul 1998 20:16:53 -0400

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Remember, 3DES not necessarily DES taken three times; I believe the most
secure (and most popular) form takes the output of DES decrypted with
another key on the second pass and then encrypted again with DES with a
third key on the third pass. It's fascinating and super-clever (and
some say "unbreakable") but it's, of course, very slow.

Whether this can be a factor of three is best left to someone else; but
it's not just DES on top of DES and it's up to someone else to decide
whether more than three iterations gives you more security.

Kris

Perry E. Metzger wrote:
>
> Mok-Kong Shen writes:
> > Xcott Craver wrote:
> >
> > > And it's pushing it to declare a cryptosystem "DED,"
> > > when simply encrypting multiple times still yields a
> > > secure (and efficient) cipher.
> >
> > If it is economically and otherwise justifiable, I also can see
> > no reason why the 3 in 3DES can't be replaced by n.
>
> Replacing it with an even number is a bad idea.
>
> .pm

-- 
Kriston J. Rehberg
http://kriston.net/
AOL: Kriston                    endeavor to persevere

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