public inbox for bitcoindev@googlegroups.com
 help / color / mirror / Atom feed
From: John Tromp <john.tromp@gmail•com>
To: Bitcoin Protocol Discussion <bitcoin-dev@lists•linuxfoundation.org>
Subject: Re: [bitcoin-dev] Floating-Point Nakamoto Consensus (bitcoin ml)
Date: Fri, 25 Sep 2020 19:23:46 +0200	[thread overview]
Message-ID: <CAOU__fxsxwakwJP6NtxVM+67U2SRj77LYKormcSO+_hmy9sG8A@mail.gmail.com> (raw)
In-Reply-To: <mailman.27861.1601049417.32591.bitcoin-dev@lists.linuxfoundation.org>

Re: Floating-Point Nakamoto Consensus (bitcoin ml)
>

> 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).

> 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


           reply	other threads:[~2020-09-25 17:24 UTC|newest]

Thread overview: expand[flat|nested]  mbox.gz  Atom feed
 [parent not found: <mailman.27861.1601049417.32591.bitcoin-dev@lists.linuxfoundation.org>]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=CAOU__fxsxwakwJP6NtxVM+67U2SRj77LYKormcSO+_hmy9sG8A@mail.gmail.com \
    --to=john.tromp@gmail$(echo .)com \
    --cc=bitcoin-dev@lists$(echo .)linuxfoundation.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox