Hm ok, it's just that there is a lot of blockchain terminology used throughout drand like "testnet", "mainnet", "chain" and so on. Seems very similar to a blockchain with similar attack scenarious but I guess it's not exactly a blockchain but somewhat similar?
> Currently it relies on the League of Entropy network, run by Cloudflare, Protocol Labs, Ethereum Foundation, Kudelski Security and other organizations, including multiple universities. So the security is relying on the fact that the network's goal is to produce public randomness, and that parties have no reason to collude. For instance the League of Entropy is used for leader election and randomness by Filecoin, so it's already "securing" a lot of things, adding timelocked data on top seems like a nice way to use the network.
I see so there is a closed group of more or less well known entities which hopefully wont be dishonest to a major degree. Closed group being the key here because that prevents whole range of attacks, most importantly sybil attacks. So the trust in the system derives from the trust into the participants.
Without researching it more I would guess that during encryption it might use the public keys of the nodes plus the round number with the threshold scheme and when the round finally arrives, the nodes then publish their private keys for this round?
I think I have a better idea of the system now. Judging by me being not the only one here who didn't understand how things work on a high level maybe the README could be expanded a bit. That would be great.
To me the beautiful thing about trying to get randomness is that as long as you have one random source then you have randomness. I.e. non-random XOR random => random.
So, you use X sources, as long as one of them is truly random then you are golden. Even if most are compromised it shouldn’t matter. Use on device security chip randomness, use user input, use external party providers etc. it all helps! (But be careful to errors when implementing, that’s hard to do!)
Only if the sources choose their numbers independently of each other. If the non-random is a function of the random source (e.g. the identity), then the result isn't random, it's a constant 0.
Probably requires too much trust in the satellite's builders, but it's a fun idea...
Whereas a server on the internet could be compromised over the internet.
> In practice this means that if you trust there are never more than the threshold t malicious nodes on the network you're relying on, you are guaranteed that you timelocked data cannot be decrypted earlier than what you intended.
So I guess this just relies on a multi key threshold scheme where t nodes have to combine their keys to decrypt the data. And I assume the blockchain tries to punish participants who refuse to take part in the decryption?
If so then this seems very tricky in terms of risk because if you have more than t malicious nodes they can secretely collude outside the chain to decrypt the data before the specified time and you'd never know in contrast to the usual attacks on blockchains which are very obvious. So the chain in that regard does not and can not add to keep the actors honest in that regard.
Would love to see the DEF CON presentation but I couldn't find a video for it. Didn't even spot it in the DEF CON timetable.