Globally Broadcasting Workshares to Improve Finality Heuristics

An interesting concept occurred to me today while chatting with Nic Carter.

If we set Bitcoin Core up to gossip headers for work shares (e.g., expected 500 headers per block would have 20kb overhead, assuming we don't need to send the prev hash) we'd be able to have more accurate finality estimates and warnings if we see hashrate abandoning our chain tip. This is observable regardless of if dishonest miners choose not to publish their work on non tip shares, since you can notice the missing work.

In the GUI, we could give users an additional warning if they are accepting a payment during a sudden hashrate decrease that they might wait longer.

Has this been discussed before?

Cheers,

Jeremy

It's not exactly what you're looking for but this is very similar to the premise of Bobtail, which was presented at Scaling Bitcoin a few years ago: https://arxiv.org/abs/1709.08750

On Fri, Dec 17, 2021, 10:54 Jeremy via bitcoin-dev < bitcoin-dev@lists•linuxfoundation•org> wrote:

> An interesting concept occurred to me today while chatting with Nic Carter.
>
> If we set Bitcoin Core up to gossip headers for work shares (e.g.,
> expected 500 headers per block would have 20kb overhead, assuming we don't
> need to send the prev hash) we'd be able to have more accurate finality
> estimates and warnings if we see hashrate abandoning our chain tip. This is
> observable regardless of if dishonest miners choose not to publish their
> work on non tip shares, since you can notice the missing work.
>
> In the GUI, we could give users an additional warning if they are
> accepting a payment during a sudden hashrate decrease that they might wait
> longer.
>
> Has this been discussed before?
>
> Cheers,
>
> Jeremy
>
> --
> @JeremyRubin <https://twitter.com/JeremyRubin>
> <https://twitter.com/JeremyRubin>
> _______________________________________________
> bitcoin-dev mailing list
> bitcoin-dev@lists•linuxfoundation•org
> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
>

Hi Jeremy,

If I understand you correctly, then I believe I touch upon this concept here: https://bitcointalk.org/index.php?topic=97153.msg1309930#msg1309930

/Rune