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DIY Random Number Generator

CmdrTaco posted more than 7 years ago | from the now-wait-a-minute dept.

227

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."

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227 comments

Pretty useful (-1, Redundant)

Anonymous Coward | more than 7 years ago | (#15898161)

The Irate Turk easily claims the first post of this thread.

Typos (5, Interesting)

fatwreckfan (322865) | more than 7 years ago | (#15898165)

I think it should read:

and how to article on...

And I have to wonder...that is less than 100.00 what?

Re:Typos (5, Funny)

Funkcikle (630170) | more than 7 years ago | (#15898170)

The "article" was clearly written by a Random English Generator, powered by tritium and chapstick.

Re:Typos (0)

Anonymous Coward | more than 7 years ago | (#15898595)

The submitter's handle is Compu486, so you can't really expect him to randomly generate a proper paragraph in a reasonable amount of time, do you?

Re:Typos (1)

mrami (664567) | more than 7 years ago | (#15898198)

I think it should read:

"less than 100.00 [% chance of getting you laid] ..."

which means not worth doing in my book.

Re:Typos (5, Funny)

also-rr (980579) | more than 7 years ago | (#15898225)

And I have to wonder...that is less than 100.00 what?

Fear not comrade, it's all part of the move to make Slashdot less US centric - this way, rather than just having foreigners confused about how much things cost, everyone gets to be confused about how much things cost.

Re:Typos (0)

Anonymous Coward | more than 7 years ago | (#15898259)

This summary is the worst I've seen in at least a few weeks...

Anyone know how much the slashdot editors actually get paid?

Re:Typos (5, Insightful)

dpninerSLASH (969464) | more than 7 years ago | (#15898281)

I have to jump on the wagon here as well.

How long would it really take to edit each post before submitting it for public consumption? Slashdot is now one arm of OSTG, and as such their content should be held to the same standards as any other "official" publication.

And please, folks, don't take the easy way out with a generic "slashdot omelet" response: It's the varying points of view that make this site not interesting, not the various manglings of the English language.

Truthfully.

Re:Typos (1)

Just Some Guy (3352) | more than 7 years ago | (#15898442)

I actually inserted a "percent" after 100.00, and was trying to figure out why an RNG using less than 100% atomic decay was so nifty.

Re:Typos (0)

Anonymous Coward | more than 7 years ago | (#15898512)

I think it should read:

and how to article on...

Don't you mean it should have read "an how to article on..."? What's with the "and"? It means "with", last time I checked.

Re:Typos (2, Insightful)

azav (469988) | more than 7 years ago | (#15898519)

Ya, I really wish we had a spelling checker for Slashdot and that the editors would actually spell check the articles they post.

If you're going to attempt to be viewed as a professional, it helps to be able to pass 5th grade English.

Cheers,

I did this in highschool (3, Interesting)

Anonymous Coward | more than 7 years ago | (#15898166)

I hooked up a geiger counter to an old school analog game port.

I had a simple C program that just spun between 0 and 255, and when a signal came across the game port it would record the current number.

run that through a hash function of your choice and it worked great.

dont cpus today have some noise generators built into them though?

Re:I did this in highschool (3, Funny)

MustardMan (52102) | more than 7 years ago | (#15898187)

Yeah, but I bet you were capable of writing a comprehensible summary of the whole setup when you were in high school

Re:I did this in highschool (0)

Anonymous Coward | more than 7 years ago | (#15898321)

Although that may be more or less random by being unpredictable to someone on the other side of the world, it'd be trivial to get about the same results from a spot right next to the geiger counter. While this was a pretty good idea in HS, it has absolutely no practical real world value.

Re:I did this in highschool (0)

Anonymous Coward | more than 7 years ago | (#15898344)

So, um, did you fail basic physics? What are chances of radiation interacted with both geiger counters exactly in sync? 0, that's what.

Re:I did this in highschool (2, Interesting)

MustardMan (52102) | more than 7 years ago | (#15898383)

And if YOU knew a bit of just slightly more advanced physics, you'd realize that radiation obeys conservation of momentum, just like everything else. It's very very easy to demonstrate direct correlation between radiation spikes measured when the detectors are the same distance from a sample, but 180 degrees apart. I did this in a sophomore lab in college with some equipment that looked like it was older than I was.

Only terrorists use random numbers! (1, Funny)

Anonymous Coward | more than 7 years ago | (#15898169)

If you have nothing to randomize, you have nothing to fear.

Editors? (5, Interesting)

AntsInMyPants (819105) | more than 7 years ago | (#15898176)

I know the English may not be the submitter's first language, but it would be nice if the editors....um, you know....*edited* the piece so it made sense.

Michael (Who now sits back and waits for people to pounce on my spelling/grammatical mistakes)

Re:Editors? (4, Funny)

WilliamSChips (793741) | more than 7 years ago | (#15898202)

"I know the English"--WRONG.
"I know that English"--RIGHT.
Hey, you asked for it!

Re:Editors? (0)

Anonymous Coward | more than 7 years ago | (#15898517)

Hey, be nice. Just because he don't be speakin' the English...

Re:Editors? (0, Redundant)

lixee (863589) | more than 7 years ago | (#15898242)

I know the English may not be the submitter's first language
It doesn't seem to be yours either.

Re:Editors? (0)

Anonymous Coward | more than 7 years ago | (#15898315)

I don't know - I've heard people talk of "speaking the English" and such. Nevertheless, there are no real editors at Slashdot, or just about any other modern website or blog. The nu-editors of the web age filter content and select articles for publication, but they don't give a shit about spelling or grammar - even in article titles! What blows my mind is that they don't go back and correct obvious and embarrassing mistakes, even after they're pointed out. Is that supposed to be journalistic integrity or something?

Re:Editors? (0)

Anonymous Coward | more than 7 years ago | (#15898533)

Corrections in bold:

I know that English may not be the submitter's first language, but it would have been nice if the editors ... um, you know, ... edited the piece so it made sense.

Michael (Who now sits back and waits for people to pounce on his spelling or grammatical mistakes.)

Day-um! (-1, Redundant)

Anonymous Coward | more than 7 years ago | (#15898179)

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."
A "how artical" -- perhaps you meant a "how-to article"? Okay. Now, a "random number generator that is less than 100.00"... 100.00 what? And look at the atrocious grammar in the second sentence!

Wake up, editors!

More difficult Rnd() generator (5, Funny)

LiquidCoooled (634315) | more than 7 years ago | (#15898183)

I once collected loads of old broken smoke detectors and ripped out the small cell of americium from each of them.
I placed them into a big ball wrapped in tinfoil (shiney side in), then used my fathers' geiger counter to supply random numbers.

Its been working well, I've been counting the number of years its been running on my fingers, so far I've got to 13.

*note, this is totally false, but there was some stupid kid who did something similar.

Re:More difficult Rnd() generator (1)

LiquidCoooled (634315) | more than 7 years ago | (#15898193)

Oh crap, after reading the article, he did use americium just not as much as I speculated.
dumb fuck...

I bet he even tweaked it so the random numbers looked random
that always confuses people when you show them a random sequence that happens to be all one number of an increasing sequence, "bah its not random"

Re:More difficult Rnd() generator (0)

Anonymous Coward | more than 7 years ago | (#15898504)

Its been working well, I've been counting the number of years its been running on my fingers, so far I've got to 13.
You've got 13 fingers now?! For Christs's sake, throw that thing away. It's not safe!

Old-school (5, Funny)

amliebsch (724858) | more than 7 years ago | (#15898188)

Whatever happened to just mashing your fists on the keyboard?

Re:Old-school (2, Insightful)

Quila (201335) | more than 7 years ago | (#15898312)

Not very random, as your fists may tend to fall in certain places when statistically analyzed.

Re:Old-school (4, Informative)

Jerf (17166) | more than 7 years ago | (#15898414)

Yes, but the programs that use this don't use just the key distribution. First, they also use the time the keystrokes occur, which is reasonably random.

Second, you can measure "how random" something is (for suitable definitions of "random") by measuring its "entropy", which is a measure of how many "random" bits is in a given input. The entropy of English text is 1.1 to 1.6 bits per character [wikipedia.org], which means to safely obtain a 128 bit key from a bit of English text you need almost as many characters as you want bits. "Smashing on the keyboard's" randomness will probably vary even more, from perhaps as low as ~.5 if you smash poorly to 2.5-3 if you smash "randomly", but you also get the entropy from the timing information, which if you use a very-high-resolution clock contributes several bits itself.

So, basically, this "statistical analysis" problem is extremely well known, and very well quantified, down to the fractional number of bits of randomness that you can extract from a bit of text. Since these fractional bits can just be added together (four "English text characters" at 1.5 bits apiece gives you 6 strongly-"random" bits), the solution turns out to be very simple: Smash on the keyboard longer, until you've got at least as much entropy as you have bits. Voila, a strongly-random key suitable for almost all purposes. (It probably is suitable for all purposes, but taking a key from radioactive decay has the advantage of letting you know the key is random, whereas with this technique you can only be "very, very, very sure".)

Handled properly, it's not a problem.

Many, if not most, modern systems will also maintain an "entropy pool" at the OS level, which uses interrupt timings and other such events to feed the pool, which can then be drawn on by programs in lieu of reading the keyboard directly. This works nicely, and among the inputs used is keyboard and mouse events.

The nice thing about the entropy pool is the input can really come from anywhere. It doesn't have to be totally random to contribute, it just can't be totally predictable.

Not as geek but safer (5, Informative)

click2005 (921437) | more than 7 years ago | (#15898192)

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

Re:Not as geek but safer (1)

Kazymyr (190114) | more than 7 years ago | (#15898511)

To: All Employees
        From: Executive Management
        Date: Sun Aug 13 09:33:39 2006
        Subject: Important Announcement

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                  This is the a web browsing tool we've all got to be galvanized around as a team going forward. With our desktop to Terra-flops strategy, the parallel human resource allocation gets your input on the performance Internet service provider. We feel that the UI critical path will enable the dealer channels.

Does anyone read these?... (-1, Redundant)

decadre (980513) | more than 7 years ago | (#15898195)

"The guys over at Inventgeek have come up with a project and how artical"

Honestly a 4 year old would have better grammar, and arical?.. I dont know what to say...

Are these guys doing it the hard way on purpose... (0)

John Hasler (414242) | more than 7 years ago | (#15898201)

...or are they just slow?

apparently (2, Insightful)

frieko (855745) | more than 7 years ago | (#15898227)

IIRC Random.org [random.org] just uses a soundcard and a radio tuned in between channels and collects atmospheric noise. Sounds much simpler/safer.

Re:apparently (1)

John Hasler (414242) | more than 7 years ago | (#15898322)

> ...a soundcard and a radio tuned in between channels and collects atmospheric
> noise.

Depends on what you are using the random numbers for. An opponent could transmit known patterns on that frequency, or the vagaries of radio propagation could replace the noise with a station.

> Sounds much simpler...

Simpler is a noise diode and a comparator. Sticking the americurium to the diode might up its output a bit.

> ...safer.

There is no significant risk.
 

Here's the money graph (5, Informative)

patio11 (857072) | more than 7 years ago | (#15898207)

>>
  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.
>>

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 (5, Informative)

patio11 (857072) | more than 7 years ago | (#15898226)

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.

Re:Here's the money graph (1, Interesting)

Anonymous Coward | more than 7 years ago | (#15898254)

Mersenne Twister plus any unknown piece of data as a seed is good enough at resisting everything our current understanding of mathematics


Isn't Blum-Blum-Shub still a better choice of algo for encryption?

Re:Here's the money graph (0)

Anonymous Coward | more than 7 years ago | (#15898479)

Isn't Blum-Blum-Shub still a better choice of algo for encryption?

Actually it's even better to run the algorithm three times over the same data. This is called the blum-blum-shub-blum-blum-shub-blum-blum-shub algorithm. (sorry)

Re:Here's the money graph (1, Insightful)

Anonymous Coward | more than 7 years ago | (#15898311)

In addition, the downside of true random numbers is that they are... random. We use (particle physics) vast amounts of random numbers in large Monte-Carlo simulations. But I can tell you, you really want to get that same sequence starting form the same seed, if you ever want to cross check things. What we need are not true random numbers, we need damn-good pseudo-random numbers. Which we have of course ;-)

Re:Here's the money graph (0)

Anonymous Coward | more than 7 years ago | (#15898333)

The Mersenne Twister is not suited for cryptography. (Read the Wikipedia page or the authors' page on this). That is, it's possible to figure out its state by observing values, even values mod something. You could take a cryptologically secure hash of it to get secure random numbers, but that slows it down, or you could get guaranteed security by using a truly random process.

Re:Here's the money graph (1)

portmapper (991533) | more than 7 years ago | (#15898405)

> 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.

In newer VIA CPUs there are instructions for pretty good randomness, but neither AMD nor
Intel seems to be willing to make similar instructions available.

Re:Here's the money graph (1)

maird (699535) | more than 7 years ago | (#15898423)

Intel has had the same thing on its chipsets for many years, i.e. an I/O device rather than a CPU instruction. IIRC, it takes around 5ms per bit. On the subject of the practical utility of the "invention", does the author now have an excellent source of one time pads for encryption? That knock at the door is the NSA or the CIA, start the fire now.

Wrong. Encryption is a valid application. (1)

njdj (458173) | more than 7 years ago | (#15898456)

Actually, no, none of these really benefit from "truly random numbers"

A random number generator is the best way to generate good cryptographic keys. Pseudo-random numbers are not good enough, in fact that is the commonest kind of "snake oil" in the encryption world. See Bruce Schneier's site [schneier.com] for examples.

A very long random sequence can be used as a one-time pad, giving completely unbreakable encryption if the sequence is truly random.

Re:Wrong. Encryption is a valid application. (2, Insightful)

kestasjk (933987) | more than 7 years ago | (#15898529)

1) The problem with one time pads isn't generating random text to XOR with, it's getting that text from A to B without relying on weaker crypto.

2) Pseudo-random number generators (with a sufficiently random seed) aren't good enough? Then maybe you'll be able to tell me what comes next after this base64 encoded output of the /dev/urandom implementation on FreeBSD:
QPoiNHKXSHYGks3IreT4sGsZgnBTdLEt6OknLOoePAmAjNof yJtbv7Jgl0KOdIqjmUwXiBzOWGaT HCJZaPGdcyVKtQk6nRGej5explzMc/GDNk1AnyDdtPP+talfMT lMjI7AThTRprNdzphOcAbwY18l r0MUKM9Y/pEbR2N1/bKd12VTc+xzNzvRB/9q4QMaDYvyzWYfkx 0UGUkxCCBWYOokUOXtFWoHI+Ki
No, the grandparent is right. By avoiding our excellent pseudo-random number generators and going with this hacked together entropy generator you're more likely to decrease your security because of flaws in the hardware than gain a practical increase in security.

Re:Here's the money graph (0)

Anonymous Coward | more than 7 years ago | (#15898470)

The question is when are you "reasonably sure" that your numbers are unpredictable. Most random number generators used in practice are based on vague unsubstantiated claims about the randomness that occurs in various environments.

It is not at all true that it is sufficient for random sequences to be unpredictable to be useful. In many application knowing even one bit of information about a purported random sequence can destroy its usefulness.

As for the necessity of randomness in various applications, it is actually essential for many things. In particular for encryption, true randomness is vital. If an encryption scheme is proved to work well when truly random sequences are used, the proof (usually) says nothing about sequences which are simply unpredictable.

For a more detailed discussion, check out:

http://www.wisdom.weizmann.ac.il/~oded/r+c.html [weizmann.ac.il]

Not practical? (1)

twitter (104583) | more than 7 years ago | (#15898490)

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. ... [blah blah blah] ... in terms of practical application this gets a near zero.

Oh, so you would not want to have an $85 seed generator would you? If 1.3 million possible combinations are not good enough for you, you could always combine more hits to get any resolution you wanted. Then you feed that back into your twister [umich.edu] or whatever. This eliminates the non random nature of your seed, which is a traditional weak point.

Re:Here's the money graph (0)

Anonymous Coward | more than 7 years ago | (#15898527)

"The applicability of randomness to AI is... spurious at best?"

Actually, randomised search is perhaps one of the most effective paradigms in a good number of AI problems: just look at any of the literature on the use of local search with restarts. Heck, it better had be, or I have to choose another topic for my PhD thesis!

Instead of making a systematic search for a solution to a problem, make a series of greedy searches guided by a heuristic, using randomness to break ties between decisions with equal heuristic values; and to, occasionally, make a random decision rather than a heuristically good decision. Restart search from scratch when a certain 'boredom threshold' has been reached - so-many steps without heuristic improvement, etc., keeping the best result found so far. The result? In many search problems, a solution can be found much faster than if the randomness was not present - the greedy search would be deterministic, returning the same solution each time, and would not take the alternative paths to potentially better solutions that the randomness introduces.

Does it need to be true randomness though, rather than pseudo-random? No, not really; and besides, it's always useful to be able to reproduce tests by using the same seed. I really wouldn't like my segfaults to be produced by a truly random process - it would make reproducing them statistically infeasible.

Why not using a live webcam? (1)

G3ckoG33k (647276) | more than 7 years ago | (#15898224)

Why not use a live webcam? Select a number of pixels as source, label them as you wish and start compute. I mean, incoming photons ought to be fairly random too.

Re:Why not using a live webcam? (1, Funny)

Anonymous Coward | more than 7 years ago | (#15898275)

That would be an interesting research topic, combining output from multiple webcams as a source of entropy. What are the chances of securing funding for myself and some hawt camgirls?

More precious than gold... (0)

Anonymous Coward | more than 7 years ago | (#15898252)

I think I'd rather the $100 rather than the random numbers.

Pretty cool, but (3, Insightful)

vadim_t (324782) | more than 7 years ago | (#15898260)

For a practical solution, I'd just get a VIA Nehemiah CPU. The later ones have an embedded RNG, and do AES at truly amazing speeds. The actual CPU performance is quite bad compared to pretty much anything else, but it makes a nice quiet box if you don't need vast amounts of CPU power.

And besides, why the emphasis on shielding the camera? You'd think that for a RNG interference is good as it adds more randomness.

Re:Pretty cool, but (1)

aXis100 (690904) | more than 7 years ago | (#15898408)

That depends if the interference is random.

I can think of lots of non-random interference sources - Mains 50Hz, CPU Clock, USB Clock, other data signal on the USB cable, etc.

units (5, Funny)

Digitus1337 (671442) | more than 7 years ago | (#15898261)

Less than 100.00! I've waited at least the past 8 for something like this!

Re:units (0)

Anonymous Coward | more than 7 years ago | (#15898445)

I've waited at least the past 8 for something like this!

Please don't exaggerate. No way it could have been more than 4.

alternate silly reply: When I was kid we waited 16, and we liked it.

I seem to remember (5, Interesting)

npcompleat (942042) | more than 7 years ago | (#15898272)

There was a study done that asked a group of people to come up with a string of random ones and zeros. Unsurprisingly, after statistical analysis, they weren't very good. But the fantastic bit was to ask another group to pair off and for each of them to try to outguess the other: let your opponent see your string of ones and zeros so far and then try to make the next bit the opposite to the one they are likely to pick. Amazingly, these random strings were impressively more random. Perhaps we've evolved special pseudo-random number generators to allow us to be sneaky.

[I know, a reference would have been nice, but age does terrible things to your internal bibtex database]

cheap alternatives (3, Informative)

flok (24996) | more than 7 years ago | (#15898277)

If you find building something yourself to much of a hassle and you have either a webcam or a soundcard lying around, you could give audio-entropyd [vanheusden.com] or video-entropyd [vanheusden.com] a try.

Another approach (2, Interesting)

FlyByPC (841016) | more than 7 years ago | (#15898278)

John Walker, of Autodesk fame, did a similar project [fourmilab.ch], although with a simpler count-the-clicks approach. I copied it using an off-the-shelf Geiger counter and a piece of Autunite; it works well.

Typically silly (2, Interesting)

m.dillon (147925) | more than 7 years ago | (#15898307)

Randomness exists in nature all over the place. In fact, in every single atom, simply because we are not living in a world that is anywhere near a temperature of absolute zero. A johnson noise generator costs a few cents. In analog electronics, keeping randomness *OUT* is actually the harder problem.

Frankly, you don't need all that much true randomness to generate random numbers. You just need to be able to continuously seed a CSPNG from a random source, and not even at a very high rate. A few bits a second is plenty.

Move along,

-Matt

We use /dev/urandom (3, Interesting)

the_duke_of_hazzard (603473) | more than 7 years ago | (#15898323)

It's good enough to have been passed by all the regulators and is used by our online gaming systems.

Re:We use /dev/urandom (0)

Anonymous Coward | more than 7 years ago | (#15898589)

It's good enough to have been passed by all the regulators and is used by our online gaming systems.
Diebold fess-up at last!

Natural Language - Integer Value (-1, Offtopic)

sdmonroe (682713) | more than 7 years ago | (#15898395)

Here is a program [monrai.com] which generates the integer value of natural language numbers, e.g. nine hundred twenty eight million two thousand fourteen --> 928,002,014. Here's the info on the release [blogspot.com]. The next step is to write a dataset for solving simple word problems.

Don't try this at home, folks! (4, Informative)

iansmith (444117) | more than 7 years ago | (#15898417)

A few things of note about dealing with smoke detector sources.

First, removing the source from a smoke detector is illegal in the US. I'm not aware of anyone being put in jail for doing it, but with the state of affairs currently I would not go posting the fact that you did it all over the internet.

Second, those sources can be very dangerous if mishandled. The source is coated in a THIN layer of gold and/or silver.. only a few atoms thick. If you touch it with anything you will break the seal and contaminate the object. If you then happen to touch it, you have a good chance of ingesting or inhaling it. This is bad. Am-231 is what is called a bone-seeker. It will be used in new bone growth and eventually kill you by causing bone tumors and other cancers.

Now with a little care you can be pretty safe, but the article in question should have been a little more explict about the dangers involved here.

Why does Inventgeek hate our freedom? (1)

FatSean (18753) | more than 7 years ago | (#15898498)

If we cannot show the government that we are responsible enough to use our smoke detectors in a safe manner, they will take them away from us!

Nitpicking correction (2, Informative)

Anonymous Coward | more than 7 years ago | (#15898515)

Am-231 is what is called a bone-seeker

The isotope used in smoke detectors is Am-241, not Am-231. Am-231 is too unstable to be listed in standard isotope tables.

Of course, all isotopes of Americium are bone-seekers, so your point remains valid, though I find it a bit nannying. The quantity of Am-241 in a smoke detector is really minute.

Re:Don't try this at home, folks! (1)

cdrguru (88047) | more than 7 years ago | (#15898558)

There was not too long ago someone in the Detroit area that assembled a great number of the innards of smoke detectors. He was trying to build something, I forget what. The net effect was that his adventure with smoke detectors required a NEST team to come in and clean up. It was not a trivial matter.

He also managed to get his hands on some other radiation sources as well, so it wasn't just some smoke detectors. However, smoke detectors are nothing to fool around with disassembling.

Re:Don't try this at home, folks! (2, Informative)

iansmith (444117) | more than 7 years ago | (#15898571)

Yes, that was David Hahn [amazon.com] who used quite a bit of social engineering to get information and equipment to build his own little breeder reactor in his mothers garden shed. A very interesting story. Lots of writeups all over the web.

Re:Don't try this at home, folks! (1)

John Hasler (414242) | more than 7 years ago | (#15898578)

> I forget what. The net effect was that his adventure with smoke detectors
> required a NEST team to come in and clean up.

It got such a team. Whether it required one is another question entirely.

Give Him a Break (2, Insightful)

justinchudgar (922219) | more than 7 years ago | (#15898432)

From the article, it seems that he was creating something to satisfy his personal curiosity. He put together a good simple plan and actually made it work. That is interesting, fun, and admirable. I did not get the feeling that he set out to save the world from pseudo-randomness; as many have noted, it does not need saving. If he made some over-enthusiastic claims about the utility of his creation, who cares, he made it and it works; and, that is cool. Now, if next week, he starts hawking them at $250.00 each for the Ultimate Internet Privacy Shield, then give him hell. :)

e-Passport as source for randomness (0)

Anonymous Coward | more than 7 years ago | (#15898450)

For a cheap and quite good random number generator, you may want to get a new e-Passport and a contactless reader. Almost any passport, at least in Europe, America etc. will implement Basic Access Control. This uses a challenge response mechanism, and the challenge is almost certainly generated by a rather strong hardware random number generator. Obviously, you may want to be sure that nobody else can eavesdrop the random numbers.

To prevent eavesdropping an alternative may be to setup the secure messaging channel first. This has the drawback that the GET CHALLENGE command may not be available within the secure messaging channel. Another method is to use the 16 byte random number present within the MUTUAL AUTHENTICATE command. This is normally used to set up the session keys, but it can also be used as a random number source.

Anyway:
Get ATR (answer to reset)
SEND 00A4040C07A0000002471001 (SELECT the application)
RETURNS 9000 (OK)
SEND 0084000008 (GET CHALLENGE command)
RETURNS 8 random bytes and 9000 (OK)
repeat GET CHALLENGE until you have enough bytes (some e-Passports may support up to 256 byte challenges).

Radiation/Science/Geek combo (2, Funny)

ElephanTS (624421) | more than 7 years ago | (#15898503)

There seems to some possiblity for the creation of a superhero here. Wonder what his ability would be?

Re:Radiation/Science/Geek combo (1)

biscon (942763) | more than 7 years ago | (#15898567)

Ehm he would be called RandomMan and bore all villains to dead with his endless reciting of boneseeking radioactive random numbers or something. As well as constantly fighting off his evil twin Dr. Integer.

Is radioactive decay really random? (1, Interesting)

dpbsmith (263124) | more than 7 years ago | (#15898546)

For the better part of a century, radioactive decay is what scientists always use when they want to invoke a natural process that is "random." But is radioactive decay really random... that is, are there, say, well-established quantum-mechanical equations that predict this? Or is it merely chaotic, or not known to be predictable... like the popping of kernels of popcorn in a microwave, or, for that matter, the spins of a roulette wheel?

Re:Is radioactive decay really random? (0)

Anonymous Coward | more than 7 years ago | (#15898605)

Radioactive decay is perfectly random (not just chaotic).
Basically, the time-dependant Schrodinger's equation tells us that after a certain time, an excited atom is in a superposition of |excited> and |relaxed> state (which is the state after the decay). If you measure the state of the atom after exactly one half-life period, you have a 50% chance of finding the atom in either the excited or relaxed state. In quantum mechanics, there is absolutly no way you can predict in which state the atom will be.

don't need radiation (2, Insightful)

roman_mir (125474) | more than 7 years ago | (#15898587)

You don't need radiation to make a randomizer from a camera. How about pointing the camera out of a window at a road. The cars, the people and other objects (birds) will move around supplying you with random data. Or you could have a transparent plastic box full of mosquitos or flies and point the camera at that ;)

How about using a soundcard and ambient noise? Or you could use an AM radio receiver for static noise. There are plenty of other sources of randomness.

Like a monkey (1)

aniefer (910494) | more than 7 years ago | (#15898626)

Some random data is needed to generate a cryptographic identity for you.

Please bang on the keyboard like a monkey.

Random Functioning Editor (0)

Anonymous Coward | more than 7 years ago | (#15898648)

Nice work Taco. Please consider taking a remedial English course sometime in the near future. If that doesn't work for you, consider taking a job with the OSTG janitorial staff -- they need help scooping out all the residual MS FUD ads /. has been bathing in these past few years.

The internal version is a bad idea (2, Insightful)

chriso11 (254041) | more than 7 years ago | (#15898650)

I don't recommend the internal PCI version - you shouldn't place a gamma emmitter (yes, for the pedantic, Am241 is PRIMARILY an alpha emmitter) inside your case. You will be increasing the odds of a memory bit flip or such.
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