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Totally Random One Time Pads
liliafan writes "Scientists in Japan have come up with a way of harnessing a truly random datasource for generating one time encryption pads: Quasars. One time encryption pads are widely accepted as being the most secure form of encryption, but this new technology from the National Institute of Information and Communications Technology makes the pads even more secure."
This is a dupe of almost the same story from the same source.
From what I hear, I'll probably be able to save on my heating bills too.
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Women have had those forever...
Getting randomness isn't interesting. Thermal noise is truly random, perfectly white, and easy to generate---it's as hard as passing a current through a resistor. Want more noise power? Avalanche breakdown, with appropriate whitening, works fine.
Unless they've come up with an interesting way for two people in disparate locations to observe the same quasar and both independently observe the same random phenomena in a way which reliably and securely gives them access to the pad with no communication channel between them, this just isn't interesting.
-rsw
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The sea changes color, but the sea does not change.
I imagine someone who wanted to could buy enough equiptment to record all known quasar emmissions and store them
or try them against encrypted data streams. A million quasars with 5000 possible frequencies each, wouldn't be that
much for a computer to churn thru. In a way, it almost seems like security thru obscurity.
The summary for this article is a little misleading. One time pads aren't new, and good sources of natural randomness aren't new either.
The interesting part of this article is the fact that quasars could be used as a natural source of randomness for one time pads, yet can be accessed by both parties simultaneously. The historical problem with one time pads (and the reason they're rarely used in practice) is that it's a huge pain to distibute sufficient random data to all parties involved in a communication. Being able to use a natural source of randomness that's available to everyone at once would be a major increase in the usability of one time pads.
...harnessing a truly random datasource
Wow, they finally managed to tap into my girlfriend's mood neurons?
[alk]
How does this increase security? It's not like quasars are private property. Anyone can look at 'em...
Intergalactic Public Key Infrastructure
It seems unlikely that it will become possible to predict the behavior of quasars as you suggest; we can't even accurately predict the weather on earth, which is a much smaller system than a quasar. For that matter, we can't predict the detailed behavior of a lava lamp, making that a reasonable source of random numbers (but patented!).
This is a Vernam Cipher with a novel but impractical noise source. It was news when Vernam invented it in 1917, and maybe again in 1919 when he patented it, but this version solves an already-solved problem in a manner that would sound really good if Lt. Colonel Carter suggested it on SG-1, but otherwise is inferior to existing solutions to the same problem.
Nothing to see here, folks; move along.
There isn't any particularly better definition of randomness than "unpredicability".
That's true not just as a rule of thumb, but in a more formal sense as well. The word "random" is pretty hard to come up with a mathematically formal definition for, and "pretty hard" may mean "impossible" depending on your definition of "definition" (more on that later). To make things simple, let's just talk about sequences of ones and zeros. Take for example the sequence 01101110010111011110001001101010111100110111101111 ... Definitions of randomness from statistics and probability just require a potentially random sequence to have all possible subsequences of a given length appear with the same frequency. That is, 0 appears exactly as often as 1; 00 appears exactly as often as 01, 10, and 11; 000 as often as 001, 010, 011, 100, 101, 110, and 111; and so on. The sequence I gave above passes those tests with flying colors. But it's not random at all. I'll put some spaces in it, and you'll see the pattern: 0 1 10 11 100 101 110 111 1000 1001 1010 1011 1100 1101 1110 1111... It's simply counting in binary. The longer you extend the sequence, the better it does in statistical randomness tests--the first few dozen bits have a pretty strong bias for 1 over 0, but that ends up as noise in the long run.
The relatively young field of information theory introduces the concept of "algorithmic randomness." The randomness of a sequence of bits is defined to be the length of the shortest Universal Turing Machine program which ouputs that sequence. In pseudocode, our example sequence is output by the program:
let i = 0
while (true) do
output i
let i = i + 1
end while
That's a comically short program to generate an arbitrarily long sequence. So the example fails tests for algorithmic randomness miserably. The fun part is that the problem of finding the shortest UTM program to generate a given sequence is provably intractable. Thanks to the the Halting Problem, you can't always tell if a given UTM program will halt or loop infinitely. All you could ever know is whether or not the program has output the desired sequence yet--if it's still running, it may do so eventually and then halt, it may output something else and then halt, or it may keep running forever. So algorithmic randomness plugs the holes in statistical randomness by trading an unreliably solvable problem for a reliably unsolvable one. You can't ever be sure a sequence is random, but you can sometimes be sure it isn't.
I got off on a bit of a tangent there about information theory, but my point is that algorithmic randomness captures what we mean by "random" much better than statistical randomness. And algorithmic randomness is just a mathematically formal way of saying "unpredictable."
The original Howling Frog is a fictional character and has no UID.