[Cryptography] quantum computers & crypto

[Peter Gutmann]

cherry <cherry at cpal.pw> writes:

>About thirty years ago, from memory, they factored the number fifteen.  Have
>they factored the number twenty one yet?

15 was factored with Shor's algorithm twenty years ago, 21 was factored just
under a decade ago.  Drawing a line through these two data points (yeah, I
know, but it's all we've got), we can see that 1,024-bit RSA will be
vulnerable to Shor's algorithm some time around 4,000 AD.  However this
ignores two problems:

The first is that, like FTL travel, things get much, much harder as you scale
up.  So the line likely isn't straight, and may in fact never reach 1,024
bits.

The second is that the Kanamits will reach earth about 1,800 years before the
theoretical vulnerability of 1,024-bit RSA occurs, so the question becomes
moot.

Peter.