There seems to be some confusion over this random number device. Perry Metzger forwarded me some information about Newbridge Microsystems and the part number of a chip that made random numbers. At the crypto BOF at hackers I mentioned that there was a need for a hardware random number generator and that I knew of some chip to do it. John Draper, who was there, expressed a desire to work on such a device. I forwarded him the information about the chip. What I didn't know was the cost or design of this chip. It appears to use a radioactive source to make random numbers. This may account for the cost. In any case, it is likely that most applications don't need this kind of chip. What is needed, though, is _some_ kind of chip. John Draper is eager to manufacture such a device, once we have a design. Would those people willing to help on this design please get in touch with him directly and start a conversation about it. The conversation could reasonably be discussed on the list, if enough are interested. FYI, random numbers are used generally to create single-use session keys in a wide variety of crypto protocols, including Diffie-Hellman key exchange. Hardware random number sources will be a standard component of all computers in the near future. As far as the design of the device itself goes, the numbers that come out of it don't have to be fully random. Non-randomness can be corrected in software. Two characteristics of the output, though will help such correction. First, the number of ones and zeros should be the same. Not only is this useful for correction, but it is easy to do in hardware. Second, effort should be made to make sure that the generator does not pick up cyclic noise from its environment. This means attention to coupling, shielding, and packaging. No extra expense, likely, but definitely to be thought about some. Eric
From: Eric Hughes <hughes@soda.berkeley.edu>
There seems to be some confusion over this random number device.
Perry Metzger forwarded me some information about Newbridge Microsystems and the part number of a chip that made random numbers. At the crypto BOF at hackers I mentioned that there was a need for a hardware random number generator and that I knew of some chip to do it. John Draper, who was there, expressed a desire to work on such a device. I forwarded him the information about the chip.
What I didn't know was the cost or design of this chip. It appears to use a radioactive source to make random numbers. This may account for the cost. In any case, it is likely that most applications don't need this kind of chip.
Just for the record... As the data sheet makes clear, it most certainly DOES NOT use a radioactive source. Its very hard to get 20kbits/sec of random numbers reliably out of any radioactive source you are going to want to be near, anyway. It operates off of thermal noise just like virtually every other such device. It should be possible to build a similar device out of ordinary discrete components without overwhelming difficulty. The only problem would be to make sure that the output was reliably random, and not overly dependant on things like temperature. Perry
Eric Hughes comments and then Perry Metzger responds:
Perry Metzger forwarded me some information about Newbridge Microsystems and the part number of a chip that made random numbers. At the crypto BOF at hackers I mentioned that there was a need for a hardware random number generator and that I knew of some chip to do it. John Draper, who was there, expressed a desire to work on such a device. I forwarded him the information about the chip.
What I didn't know was the cost or design of this chip. It appears to use a radioactive source to make random numbers. This may account for the cost. In any case, it is likely that most applications don't need this kind of chip.
Just for the record... As the data sheet makes clear, it most certainly DOES NOT use a radioactive source. Its very hard to get 20kbits/sec of random numbers reliably out of any radioactive source you are going to want to be near, anyway. It operates off of thermal noise just like virtually every other such device.
It should be possible to build a similar device out of ordinary discrete components without overwhelming difficulty. The only problem would be to make sure that the output was reliably random, and not overly dependant on things like temperature.
Perry
Perry is correct. Getting 10K or more bits per second from a radioactive soure usually means it is close enough/strong enough to "drift" the device to the point of radiation-induced permanent failure in a matter of weeks or months (if not much sooner, but this is all so dependent on exact calculations and lab experiments). Tony Patti, editor of a small crypto journal and frequent commentator on sci.crypt, is one of several folks who've designed thermal noise-based RNGs. He's selling them, as I recall. I would _strongly_ advise anyone who's contemplating building and selling such a gizmo to first see what the market has produced and whether or not it's selling, etc. A minor note: the bias between 0s and 1s (unequal distribution, for example) is easily handled by considering pairs of numbers, with a "0 1" being called a "0" and a "1 0" being called a "1." --Tim -- .......................................................................... Timothy C. May | Crypto Anarchy: encryption, digital money, tcmay@netcom.com | anonymous networks, digital pseudonyms, zero 408-688-5409 | knowledge, reputations, information markets, W.A.S.T.E.: Aptos, CA | black markets, collapse of governments. Higher Power: 2^756839 | PGP Public Key: awaiting Macintosh version.
participants (3)
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Eric Hughes -
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tcmay＠netcom.com