The Key Vanishes: Scientist Outlines Unbreakable Code

[Ray Dillinger]

On Wed, 21 Feb 2001, Tom wrote:

>Ray Dillinger wrote:

>> What if it was just a few dozen Blum-Blum-Shub generators
>> up there spewing all those bits?  We'd never see the
>> difference, but a data thief who was "in the know" about
>> how they were keyed could recreate any sequence at any time.

>my point exactly. one way or the other you can't TRUST the stream,
>therefore it is worthless.

Here's an interesting thought, though.  There are all kinds of 
number generators already hanging in the sky, and some of them 
are fairly random, so this thing might actually have a prayer 
of working.

Take a good telescope, and focus on, eg, Jupiter's Red Spot. 
(ignoring for a moment the problems of focus and synchronization).
That's turbulence - a pretty damn good source of randomness. 
If Bob and Alice can see the same image, and derive the same 
stream of random numbers from it, this scheme might be salvaged 
yet. The bandwidth wouldn't be quite as high, especially allowing 
for enough "roughness" to keep it likely that the number streams 
Alice and Bob get have enough correlation to work with - but it 
might serve. 


				Ray