DIY Random Number Generator

Compu486 writes "The guys over at Inventgeek have come up with a project and how artical on building a random number generator that is less than 100.00 utilizing radioactive decay. Using some Linux based open source apps and with a little ingenuity and some parts you probably have laying around your house you can build your own."

Comments

Not as geek but safer

[click2005]

This project seems to work well... http://www.lavarnd.org/

Here's the money graph

[patio11]

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  One of the applications I have envisioned for this project is a cheap and easy genuine random number generator. True random numbers in computing are nearly impossible, and successful solutions are very expensive systems based on radioactive decay or atmospheric measurements, for example. Using a small / relatively safe radioactive source and a high res CCD or CMOS sensor and assigning a value to each pixel and perhaps mixing in an algorithm or two with an inexpensive practical PCI card that is capable of generating genuine random numbers. Applications that could greatly benefit from this would be encryption, security applications, Computer AI and the Gambling establishment to name a few.
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Actually, no, none of these really benefit from "truly random numbers". The applicability of randomness to AI is... spurious at best? For gambling, you just have to be reasonably sure that someone can't predict in advance what your random sequence is going to be, and the Mersenne Twister plus any unknown piece of data as a seed is good enough at resisting everything our current understanding of mathematics can throw at it. (Yes, thats security through obscurity... in the same way that hiding your server behind locked doors, a firewall, and a secure password is security through obscurity. Its both necessary and sufficient.)

Encryption, similarly, would not benefit from transitioning from an "almost perfect" pseudo-random generator to a "perfect" random generator. For your security to fall based on random numbers, someone needs to be able to not just come up with a theoretical imperfection (ahah, 200 million runs of this random number generator and you'll notice it slightly skews away from these five integers!) but have to crack it wide open. Yay, yawn.

Now, radiation + poorly understood mathematics = geek high, I know. But in terms of practical application this gets a near zero.

Clarification regarding Twister

[patio11]

P.S. Clarification: if you're using the Mersenne Twister in a *real life* application that plus a seed value is good enough for a gambling application. For example, if you're generating nice big integers and then taking %6 to get the value of a die or using them to shuffle one or ten or a hundred decks of cards. If, on the other hand, you have some contrived game where you are passing the output directly to the player and continue in the same sequence for a rather improbably long time a player could figure out what sequence the Twister was on and then successfully predict all numbers in advance. But this is one of those earn-you-bonus-points-with-your-CS-professor-and-n ever-use-again pieces of trivia, because in the real world you have to basically design the system to fail for it to fail in this manner.