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