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Date: Fri, 11 Sep 2015 20:37:34 +0200
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From: =?UTF-8?B?Sm9yZ2UgVGltw7Nu?= <jtimon@jtimon.cc>
To: Christophe Biocca <christophe.biocca@gmail.com>
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Cc: Bitcoin Dev <bitcoin-dev@lists.linuxfoundation.org>
Subject: Re: [bitcoin-dev] Bitcoin Days Destroyed as block selection
heuristic
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On Sep 11, 2015 1:18 PM, "Christophe Biocca" <christophe.biocca@gmail.com>
wrote:
>
> It's pretty obvious that Dave is suggesting an alternate tie-breaker:
I thought he was proposing a new consesnsus rule. I see, this would be just
a policy validation that everybody would be free to ignore (like the "first
seen" spend conflict tx replacement policy).
I don't see how miners would benefit from running this policy so I would
not expect them to run it in the long run (like the "first seen" spend
conflict tx replacement policy).
If miners don't use it, I don't see how users can benefit from running that
policy themselves.
They will still have to keep waiting some block confirmation to
exponentially reduce the chances of a successful double-spend attack with
each new confirmation (as explained in the bitcoin white paper).
> Mind you, that risk doesn't apply if we prefer non-empty blocks to
> empty blocks and leave it at that, or only switch if the new block
> doesn't double spend transactions in the old one, so it's a fixable
> issue.
How do you know which of 2 blocks with the same height is "newer"?
> On 11 September 2015 at 12:32, Jorge Tim=C3=B3n
> <bitcoin-dev@lists.linuxfoundation.org> wrote:
> >
> > On Sep 11, 2015 12:27 PM, "Dave Scotese via bitcoin-dev"
> > <bitcoin-dev@lists.linuxfoundation.org> wrote:
> >>
> >> Rather than (promising to, and when they don't actually, at least
> >> pretending to) use the first-seen block, I propose that a more
sophisticated
> >> method of choosing which of two block solutions to accept.
> >
> > There's already a criterion to chose: the one with more work (in valid
> > blocks) on top of it.
> >
> >
> > _______________________________________________
> > bitcoin-dev mailing list
> > bitcoin-dev@lists.linuxfoundation.org
> > https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
> >
--f46d0444e9e95b90eb051f7d026f
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<p dir=3D"ltr"><br>
On Sep 11, 2015 1:18 PM, "Christophe Biocca" <<a href=3D"mailt=
o:christophe.biocca@gmail.com">christophe.biocca@gmail.com</a>> wrote:<b=
r>
><br>
> It's pretty obvious that Dave is suggesting an alternate tie-break=
er:</p>
<p dir=3D"ltr">I thought he was proposing a new consesnsus rule. I see, thi=
s would be just a policy validation that everybody would be free to ignore =
(like the "first seen" spend conflict tx replacement policy).</p>
<p dir=3D"ltr">I don't see how miners would benefit from running this p=
olicy so I would not expect them to run it in the long run (like the "=
first seen" spend conflict tx replacement policy).<br>
If miners don't use it, I don't see how users can benefit from runn=
ing that policy themselves.<br>
They will still have to keep waiting some block confirmation to exponential=
ly reduce the chances of a successful double-spend attack with each new con=
firmation (as explained in the bitcoin white paper).</p>
<p dir=3D"ltr">> Mind you, that risk doesn't apply if we prefer non-=
empty blocks to<br>
> empty blocks and leave it at that, or only switch if the new block<br>
> doesn't double spend transactions in the old one, so it's a fi=
xable<br>
> issue.</p>
<p dir=3D"ltr">How do you know which of 2 blocks with the same height is &q=
uot;newer"?</p>
<p dir=3D"ltr">> On 11 September 2015 at 12:32, Jorge Tim=C3=B3n<br>
> <<a href=3D"mailto:bitcoin-dev@lists.linuxfoundation.org">bitcoin-d=
ev@lists.linuxfoundation.org</a>> wrote:<br>
> ><br>
> > On Sep 11, 2015 12:27 PM, "Dave Scotese via bitcoin-dev"=
;<br>
> > <<a href=3D"mailto:bitcoin-dev@lists.linuxfoundation.org">bitc=
oin-dev@lists.linuxfoundation.org</a>> wrote:<br>
> >><br>
> >> Rather than (promising to, and when they don't actually, =
at least<br>
> >> pretending to) use the first-seen block, I propose that a mor=
e sophisticated<br>
> >> method of choosing which of two block solutions to accept.<br=
>
> ><br>
> > There's already a criterion to chose: the one with more work =
(in valid<br>
> > blocks) on top of it.<br>
> ><br>
> ><br>
> > _______________________________________________<br>
> > bitcoin-dev mailing list<br>
> > <a href=3D"mailto:bitcoin-dev@lists.linuxfoundation.org">bitcoin-=
dev@lists.linuxfoundation.org</a><br>
> > <a href=3D"https://lists.linuxfoundation.org/mailman/listinfo/bit=
coin-dev">https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev</a=
><br>
> ><br>
</p>
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