Re: Quantum computing

Ian Woolf (ian@nospam.ftoomsh.socs.uts.edu.au)
Mon, 8 May 1995 16:26:02 +1000 (EST)

On Fri, 5 May 1995, Cameron Hutchison wrote:

> Once upon a time Ian Woolf said...
> >
> > The blackbox in the movie Sneakers is now a technical possibility, its
> > only a matter of time. factoring large numbers turns out to be the
> > easiest application to program on a Quantum logic based computer. You can
> > crack all public key large-prime-number based algorithms in seconds with
> > such a device when its finally built.
>
> I dont understand how this black box is possible. If we have a box with
> ten thousand times the computing power of the current biggest supercomputer,
> cant we just use that box to generate our keys (1,000,000 bit key lengths)?

You get EXPONENTIAL speedup with Quantum computing methods, which means a
10000 operations per second, will operate at 2^1000, two to the power of
a thousand operations a second. So it will solve RSA in the time it takes
to encrypt it. Quantum cryptography is not crackable by these means as it
operates on different principles. There are pointers to papers and info
on Quantum cryptography and computing on my home page.

http://ftoomsh.socs.uts.edu.au/~ian/ Ian Woolf
ian@nospam.ftoomsh.socs.uts.edu.au 4/267 Mowbray Rd
iwoolf@nospam.sleeper.apana.org.au Chatswood 2067, Australia
The nicer guy it couldn't happen to. Phone: +61 2 415 1132