4 ms·

To nitpick slightly, I think "truly random" is the wrong phrase here. Computers can't generate such numbers (only pseudo-random). What they can do is generate u

To nitpick slightly, I think "truly random" is the wrong phrase here. Computers can't generate such numbers (only pseudo-random). What they can do is generate unpredictable passwords. Unpredictability is the feature we want in a password, whether that happens through "randomness" or something else doesn't matter. Of course computers are far better at coming up with unpredictable passwords than humans are.

zokier 8y ago
RDRAND is supposed to generate very true random numbers
- ChrisSD 8y ago
  Well either a RNG generates true random numbers or it doesn't. There's no room for "very" here. From Intel[0] > With respect to the RNG taxonomy discussed above, the DRNG follows the cascade construction RNG model, using a processor resident entropy source to repeatedly seed a hardware-implemented CSPRNG. Unlike software approaches, it includes a high-quality entropy source implementation that can be sampled quickly to repeatedly seed the CSPRNG with high-quality entropy. So it's a cryptographically secure pseudo random number generator that takes entropy from the processor. It's not a True Random Number Generator. And again, if it does work well for cryptography, it's the unpredictability that matters, not the randomness itself. [0] https://software.intel.com/en-us/articles/intel-digital-random-number-generator-drng-software-implementation-guide https://software.intel.com/en-us/articles/intel-digital-rand...
  - zokier 8y ago
    From the link you provided: > This method of digital random number generation is unique in its approach to true random number generation in that it is implemented in the processor’s hardware > The all-digital Entropy Source (ES), also known as a non-deterministic random bit generator (NRBG), provides a serial stream of entropic data in the form of zeroes and ones. > The ES runs asynchronously on a self-timed circuit and uses thermal noise within the silicon to output a random stream of bits at the rate of 3 GHz What on earth would classify as TRNG if not above? Just fyi, checked, and NIST SP 800-90B defines NRBG as following: > Non-deterministic Random Bit Generator (NRBG): > An RBG that always has access to an entropy source and (when working properly) produces outputs that have full entropy (see SP 800-90C). Also called a true random bit (or number) generator (Contrast with a DRBG).

zokier 8y ago

RDRAND is supposed to generate very true random numbers

ChrisSD 8y ago
Well either a RNG generates true random numbers or it doesn't. There's no room for "very" here. From Intel[0] > With respect to the RNG taxonomy discussed above, the DRNG follows the cascade construction RNG model, using a processor resident entropy source to repeatedly seed a hardware-implemented CSPRNG. Unlike software approaches, it includes a high-quality entropy source implementation that can be sampled quickly to repeatedly seed the CSPRNG with high-quality entropy. So it's a cryptographically secure pseudo random number generator that takes entropy from the processor. It's not a True Random Number Generator. And again, if it does work well for cryptography, it's the unpredictability that matters, not the randomness itself. [0] https://software.intel.com/en-us/articles/intel-digital-random-number-generator-drng-software-implementation-guide https://software.intel.com/en-us/articles/intel-digital-rand...
- zokier 8y ago
  From the link you provided: > This method of digital random number generation is unique in its approach to true random number generation in that it is implemented in the processor’s hardware > The all-digital Entropy Source (ES), also known as a non-deterministic random bit generator (NRBG), provides a serial stream of entropic data in the form of zeroes and ones. > The ES runs asynchronously on a self-timed circuit and uses thermal noise within the silicon to output a random stream of bits at the rate of 3 GHz What on earth would classify as TRNG if not above? Just fyi, checked, and NIST SP 800-90B defines NRBG as following: > Non-deterministic Random Bit Generator (NRBG): > An RBG that always has access to an entropy source and (when working properly) produces outputs that have full entropy (see SP 800-90C). Also called a true random bit (or number) generator (Contrast with a DRBG).