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Comment by azinman2 | Hacker News Reader

“DO NOT USE BEACON GENERATED VALUES AS SECRET CRYPTOGRAPHIC KEYS.”

Can this at least be used to seed a CSPRNG at boot / device install, ideally with a mix of other entropy available? Is the problem that they’re shared for everyone at some given time?

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You need a TLS connection to get the NIST beacon, which requires a seeded rng. That seems like a chicken and egg problem.

As long as this data was signed by NIST, and we trusted NIST, there should be no need for TLS.

except that you would need to download the _entire_ random number sequence blockchain history instead of, say, specific parts. Otherwise, the specific parts you download would be known and therefore part of your randomness would be known.

This might be used as a public and neutral source for games based on random I guess (lotteries, etc.).

Everyone would be able to verify one game's result by checking the public entropy source at toss time.

If you already have good entropy source to mix with, how would NIST data help you? And if by CSPRNG you mean /dev/urandom, that is being used in crypto, too.

Anyone who knows the time you retrieved the seed can determine what the seed was.

Yes. I don't get this. If the 512 bits that are generated every minute are publicly known then they certainly aren't useful for any function where the seed is meant to be some sort of secret.

If someone know that you are using only this, they can try to guess when you get your numbers and use brute force with all the options. For example if they know the day, they must only try the 1440 possible minutes.

Something similar was used in the early days of HN: "How I Hacked Hacker News (with arc security advisory)" https://news.ycombinator.com/item?id=639976 (928 points, 2968 days ago, 79 comments) [note that HN was much smaller these days, 928 points was a LOT of points]

Exactly, which is why NIST is soliciting feedback on novel uses (because lots of existing uses of random seeds are intended for use as secrets).

If you mix enough real entropy together, adding this but beacon won't making things any worse, but it won't help at all.

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