Re: Braided ciphers

From: David Wagner (daw@mozart.cs.berkeley.edu)
Date: 02/10/03 

From: daw@mozart.cs.berkeley.edu (David Wagner)
Date: Sun, 9 Feb 2003 23:11:52 +0000 (UTC)

Ahh, so are you saying you're seeking a way to compose two block ciphers
so that the result is at least as strong as the stronger of the two
ciphers? If so, there are better ways to achieve this than "braiding".
For instance, one can run the two ciphers in OFB or CTR mode and xor
their outputs. Or, one can use superencryption (first encrypt with the
first block cipher, then encrypt that result with the second cipher),
which should do the trick (modulo a few theoretical issues, a la Maurer
and Massey).

Relevant Pages

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