4 ms·

Do you have any recommendations for other, high quality, sources of entropy?

lathiat 9y ago
In most cases you can use the Intel CPU included RNG by installed rng-tools to feed it into the kernel entropy pool Otherwise I’d be happier using a similarly priced USB tool that is at least designed for the job such as the ChaosKey which is also open hardware and firmware and has a Linux driver in tree
- paulie_a 9y ago
  With all the issues with Intel, I would be weary of trusting their implementation.
  - dchest 9y ago
    Analysis of Intel’s Ivy Bridge Digital Random Number Generator http://www.rambus.com/wp-content/uploads/2015/08/Intel_TRNG_Report_20120312.pdf http://www.rambus.com/wp-content/uploads/2015/08/Intel_TRNG_...
  - jnbiche 9y ago
    It's "wary". The word "weary" means tired. Edit: Just curious: are people downvoting because they disagree with my proposed spelling, or because they don't like the correction? Please let me know so I can integrate this knowledge into future comments.
jk2323 9y ago
Avalanche noise... https://emergent.unpythonic.net/01257868826 https://emergent.unpythonic.net/01257868826
- Tomte 9y ago
  No. The main problem is not the type of physical process, but the lack of any detection of failures. Hardware fails. Can you reliably detect that? The board you linked to cannot at all. Most HWRNGs can, but only partially.
DamonHD 9y ago
In general, use a pool and worry less for most purposes as long as some of them are good enough. An old project of mine: http://random.hd.org/ http://random.hd.org/ It was good enough to use for a financial application when whitened / XORed with system sources.
Kagerjay 9y ago
Cloudflare uses a wall full of lava lamps, theres a tom scott video on it https://youtu.be/1cUUfMeOijg https://youtu.be/1cUUfMeOijg
squarefoot 9y ago
Thermal and other noise by analog electronic parts (resistors, transistors pushed to high gain etc.) comes to mind. They are much safer compared to an online service, app or a piece of hardware one doesn't have the source for, but I have no idea if that noise is good once sampled to be used in cryptography or other non-analog fields.
- DanBC 9y ago
  You have to sample the noise, and deskew it, and check the components are still operating. This is where the errors normally lie. It's probably a fun project to try, but I'd be wary of using it for cryptography if only because we have other better methods. I collected a bunch of links a while ago. Here they are, I don't know if these are still working or interesting, but they might be useful: https://news.ycombinator.com/item?id=6060636 https://news.ycombinator.com/item?id=6060636
  - mikevin 9y ago
    Thanks for this! I was looking for something like this to play with.
zuzun 9y ago
FSF sells a true random number generator: [1] https://shop.fsf.org/storage-devices/neug-usb-true-random-number-generator https://shop.fsf.org/storage-devices/neug-usb-true-random-nu... [2] https://lwn.net/Articles/647502/ https://lwn.net/Articles/647502/ [3] https://lwn.net/Articles/648550/ https://lwn.net/Articles/648550/
mtreis86 9y ago
A geiger counter next to an ionization smoke detector should have some entropy, though I don't know how high the quality would be. https://www.sparkfun.com/products/14209 https://www.sparkfun.com/products/14209 https://www.newegg.com/Product/Product.aspx?Item=0EF-005S-00040&cm_re=ionization_smoke_alarm-_-0EF-005S-00040-_-Product https://www.newegg.com/Product/Product.aspx?Item=0EF-005S-00...
howard941 9y ago
If on an embedded system the low order bit of an infrequently sampled ADC input might be acceptable.
widea 9y ago
Infnoise: https://github.com/waywardgeek/infnoise https://github.com/waywardgeek/infnoise https://www.tindie.com/products/WaywardGeek/infinite-noise-true-random-number-generator/ https://www.tindie.com/products/WaywardGeek/infinite-noise-t...

In most cases you can use the Intel CPU included RNG by installed rng-tools to feed it into the kernel entropy pool Otherwise I’d be happier using a similarly priced USB tool that is at least designed for the job such as the ChaosKey which is also open hardware and firmware and has a Linux driver in tree

paulie_a 9y ago
With all the issues with Intel, I would be weary of trusting their implementation.
- dchest 9y ago
  Analysis of Intel’s Ivy Bridge Digital Random Number Generator http://www.rambus.com/wp-content/uploads/2015/08/Intel_TRNG_Report_20120312.pdf http://www.rambus.com/wp-content/uploads/2015/08/Intel_TRNG_...
- jnbiche 9y ago
  It's "wary". The word "weary" means tired. Edit: Just curious: are people downvoting because they disagree with my proposed spelling, or because they don't like the correction? Please let me know so I can integrate this knowledge into future comments.

jk2323 9y ago

Avalanche noise... https://emergent.unpythonic.net/01257868826 https://emergent.unpythonic.net/01257868826

Tomte 9y ago
No. The main problem is not the type of physical process, but the lack of any detection of failures. Hardware fails. Can you reliably detect that? The board you linked to cannot at all. Most HWRNGs can, but only partially.

DamonHD 9y ago

In general, use a pool and worry less for most purposes as long as some of them are good enough. An old project of mine: http://random.hd.org/ http://random.hd.org/ It was good enough to use for a financial application when whitened / XORed with system sources.

Kagerjay 9y ago

Cloudflare uses a wall full of lava lamps, theres a tom scott video on it https://youtu.be/1cUUfMeOijg https://youtu.be/1cUUfMeOijg

squarefoot 9y ago

Thermal and other noise by analog electronic parts (resistors, transistors pushed to high gain etc.) comes to mind. They are much safer compared to an online service, app or a piece of hardware one doesn't have the source for, but I have no idea if that noise is good once sampled to be used in cryptography or other non-analog fields.

DanBC 9y ago
You have to sample the noise, and deskew it, and check the components are still operating. This is where the errors normally lie. It's probably a fun project to try, but I'd be wary of using it for cryptography if only because we have other better methods. I collected a bunch of links a while ago. Here they are, I don't know if these are still working or interesting, but they might be useful: https://news.ycombinator.com/item?id=6060636 https://news.ycombinator.com/item?id=6060636
- mikevin 9y ago
  Thanks for this! I was looking for something like this to play with.

zuzun 9y ago

FSF sells a true random number generator: [1] https://shop.fsf.org/storage-devices/neug-usb-true-random-number-generator https://shop.fsf.org/storage-devices/neug-usb-true-random-nu... [2] https://lwn.net/Articles/647502/ https://lwn.net/Articles/647502/ [3] https://lwn.net/Articles/648550/ https://lwn.net/Articles/648550/

mtreis86 9y ago

A geiger counter next to an ionization smoke detector should have some entropy, though I don't know how high the quality would be. https://www.sparkfun.com/products/14209 https://www.sparkfun.com/products/14209 https://www.newegg.com/Product/Product.aspx?Item=0EF-005S-00040&cm_re=ionization_smoke_alarm-_-0EF-005S-00040-_-Product https://www.newegg.com/Product/Product.aspx?Item=0EF-005S-00...

howard941 9y ago

If on an embedded system the low order bit of an infrequently sampled ADC input might be acceptable.

widea 9y ago

Infnoise: https://github.com/waywardgeek/infnoise https://github.com/waywardgeek/infnoise https://www.tindie.com/products/WaywardGeek/infinite-noise-true-random-number-generator/ https://www.tindie.com/products/WaywardGeek/infinite-noise-t...