• Honytawk@lemmy.zip
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    1 year ago

    It is all based upon calculations with known numbers.

    A computer can’t create a number out of nothing.

    That is why Cloudflare uses lava lamps to generate random numbers for their cryptography. And even those aren’t fully random.

    • vrighter@discuss.tchncs.de
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      1 year ago

      Modern cpus actually do have trng hardware built in. So yes, modern computers can create numbers out of nothing, because they have specialized hardware to do so

    • FooBarrington@lemmy.world
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      1 year ago

      No, CloudFlare doesn’t use lava lamps to generate random numbers, that was a marketing stunt. Using a camera in a completely dark room is a better source of entropy than one pointed at lava lamps.

      Also, nobody is saying that computers create a number out of nothing. The environment is a great source of entropy (temperature fluctuations, user inputs and so on) which are then expanded into a larger amount of entropy through CSPRNGs.

      • Karyoplasma@discuss.tchncs.de
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        1 year ago

        Using a camera in a completely dark room is a better source of entropy than one pointed at lava lamps.

        Why is that? Naturally occurring or manufacturing-related impurities in the optical chip?

        • FooBarrington@lemmy.world
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          1 year ago

          All digital cameras are imperfect - there is always a bit of noise, but usually it doesn’t come through since your scene is bright enough to make small amounts of noise imperceptible. In a completely dark room the camera still tries to get data from the photo sensor, but the noise (created by temperature fluctuations, imperfections in the chip itself and so on) is all you get. You may theoretically be able to predict the noise on short time scales, but it’s a chaotic system.