long-term GPG signing key

Ian G iang at systemics.com
Fri Jan 13 10:32:52 EST 2006

Alexander Klimov wrote:
> On Wed, 11 Jan 2006, Ian G wrote:
>>Even though triple-DES is still considered to have avoided that
>>trap, its relatively small block size means you can now put the
>>entire decrypt table on a dvd (or somesuch, I forget the maths).
> This would need 8 x 2^{64} bytes of storage which is approximately
> 2,000,000,000 DVD's (~ 4 x 2^{32} bytes on each).
> Probably, you are referring to the fact that during encryption of a
> whole DVD, say, in CBC mode two blocks are likely to be the same
> since there are an order of 2^{32} x 2^{32} pairs.

Thanks for the correction, yes, so obviously I
muffed that one.  I saw it mentioned on this list
about a year ago, but didn't pay enough attention
to recall the precise difficulty that the small
block size of 8 bytes now has.

A few calculations here - even blueray disks won't
help me out.


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