Using Lasers To Generate Random Numbers Faster

Pranav writes "Using semiconductor lasers, scientists from Takushoku University, Saitama University, and NTT Corporation achieved random number rates of up to 1.7 gigabits per second, which is about 10 times higher than the second-best rate, produced using a physical phenomenon. Future work may center on devising laser schemes that can achieving rates as high as 10 Gbps."

Quantum Choas

[physburn]

I'm busy trying to get my head around, why partially reflecting laser light back into the laser, induces a chaotic signal. It doesn't seem right, there's a laser frequency and two reflection distances, (remember lasers have a mirror at each end). It doesn't seem complex enough to be chaotic.

If it is chaotic and you believe in the Everett Interpretation, they've just produced the worlds fastest world splitter.

Re:A Solution in Search of a Problem

[Yetihehe]

From your link to wikipedia:

Unlike Blum Blum Shub [wikipedia.org], the algorithm in its native form is not suitable for cryptography. Observing a sufficient number of iterates (624 in the case of MT19937) allows one to predict all future iterates.

So MT may be good enough for computational physicists, but not for strong cryptography.

Re:A Solution in Search of a Problem

[Anonymous Coward]

Has anyone out there actually had their system bottlenecked by lack of random numbers? I had thought that the bottleneck in serving large amounts of SSL content was processing the asymmetric part of the cyrpto -- hence the need for SSL accelerator cards. It's a nice invention and a creative application of physical process, but I really want to see just one case where this would be lead to a substantial benefit.

As an aside, computer simulations always use pseudoRNGs like the Mersenne Twister[1]. For a reasonable exponent (I use 19937 in my simulations), this results in a period > 10^6000 and virtually no correlations between adjacent calls. The notion of a computational physicist using a real physical RNG is laughable.

[1] http://en.wikipedia.org/wiki/Mersenne_twister [wikipedia.org]

Proof that you can completely fail to understand the subject, (for some reason) post about it anyway, refer to something completely unrelated, and still get a +5 Insightful.

Re:Random generator needed in semi-conductors

[ishmalius]

Reverse-biased zener diodes make an excellent noise source for true physical randomness. You want quantum quality? Use a tunnel diode. And some military radios use FM discriminator or PLL noise as a generator for crypto.

Re:A Solution in Search of a Problem

[Vellmont]

My research team used it a lot and it's nearly impossible without a good RNG.

The question on my mind (and on many others I'm guessing) is why you would need a true RNG, and not a pseudo RNG.