Re: 256-bit Camellia vs 256-bit AES - Which is better?

[Terra Frost <terrafrost () gmail com>]

On Tue, Feb 17, 2009 at 6:08 PM, Shailesh Rangari <shailesh.sf () gmail com> wrote:

> - both use the 'Fiestel Network' (first used in Lucifer & DES). Its essence
> is Decryption is done by Reversing the order of Encryption.

That's incorrect.  In DES, the only difference between the encryption
and decryption is the order in which the round keys are used.  That's
pretty much the definition of a Fiestel Network.

In AES, in contrast, the differences between encryption and decryption
are a bit more pronounced.  Take a look at fips-197.pdf#page=25 and
fips-197.pdf#page=19.  The only function shared by both is
AddRoundKey.  SubBytes and InvSubBytes differ in that they use
different S-Boxes, InvShiftRows and ShiftRows shift the rows in
opposite directions, and MixColumns and InvMixColumns with a different
fixed polynomial.

fips-197.pdf can be found here:

http://csrc.nist.gov/publications/fips/fips197/fips-197.pdf