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I just read High performance physical random number generator by K.H. Tsoi, K.H. Leung and P.H.W. Leong. It proposes a physical RNG of speed 400 Mbps. Is this the fastest random number generator at this moment?

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Did you really mean to to use the PRG tag? E.g. Intel CPUs can use AES-NI at speeds of around 2 cycles per byte, which means at least a few Gbps for an AES-based PRG. – otus Jun 23 '14 at 17:01
Why do you care? It's not like you need more than 256 bits of true random data to seed a great PRNG, which can exceed 10 Gbit/s on a modern CPU. – CodesInChaos Jun 23 '14 at 17:03
Are you looking for true random numbers, a cryptographic-strength pseudorandom number generator, or a non-cryptographic pseudorandom generator? Please edit the question to state explicitly. Also please edit the question to respond to the other questions in the comments. – D.W. Jun 23 '14 at 23:32
@otus And they contain a hardware based RNG as well nowadays. I'm pretty sure it will be over 50 MB/s. – Maarten Bodewes Jun 24 '14 at 12:01
@owlstead, RDRAND is supposed to be around 500 MB/s, but mine doesn't have it so I haven't tested. – otus Jun 24 '14 at 12:05
up vote 8 down vote accepted

The problem with questions that ask for “the fastest” is, that such questions always raise the counter-question: compared to what exactly? Also, your question doesn’t specify if you mean cryptographically secure physical random number generators, or any physical random number generator.

Anyway… 400 Mbps doesn’t really come anywhere near the word “fastest”.

If you take a look at “An optical ultrafast random bit generator”, which was published in Nature Photonics (Volume 4, Issue 1, pp. 58–61) by Kanter et al in 2010, you’ll see that their physical random bit generator operated at a rate of 300 gigabits per second. I’ld say that somewhat fits the word “faster”.

Besides that, you’ll most certainly also will want to check out “Real time demonstration of high bitrate quantum random number generation with coherent laser light”, published by Symul at al (ANU, Appl. Phys,. Lett. 98, 231103) in 2011. In short: researchers at the Australian National University are generating true random numbers from a physical quantum source.

Currently (meaning: at the time of writing this answer), their Quantum Random Number Generator seems to be the best fit for the word “fastest”.

To learn more about the QRNG, you could either start by reading this ScienceDaily article, or you can skip that and directly visit the “ANU Quantum Optics – Quantum Random Number Generator” webpage.

An aside: as others already hinted at in their comments ⁽¹⁾ ⁽²⁾, even simpler RNGs already tend to break the 400 Mbps mark.

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