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Bitcoin Dev Archive 2020

Floating-Point Nakamoto Consensus (bitcoin ml)

1 message, 25 Sep 2020. Started by John Tromp.

John Tromp

Permalink Original thread on gnusha.org

John Tromp permalink original

Re: Floating-Point Nakamoto Consensus (bitcoin ml)

Quoted text (2 lines)
>

> This is a pretty big departure from cumulative POW.

It's still cumulative. But instead of cumulating network difficulty, they cumulate log_2(solution difficulty).

So if two solutions are found simultaneously, and one has a hash that's only half of the other, then that will have twice the solution difficulty and thus contribute 1 more the cumulate log_2(solution difficulty).

Quoted text (8 lines)
> Could you explain to me what you see happening if a node with this patch
> and no history starts to sync, and some random node gives it a block
> with a better fitness test for say height 250,000? No other solution
> will have a better fitness test at that height, so from my understanding
> its going to stop syncing. How about even later - say this proposal is
> activated at block 750,000. At 850,000, someone decides it'd be fun to
> publish a new block 800,000 with a better fitness test. What happens the
> 50,000 blocks?

Nothing happens in these cases, as the new blocks are still far behind the tip in cumulative score (they just have higher score at their height).

regards, -John