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Date: Fri, 4 Dec 2015 12:34:27 -0500
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From: Gavin Andresen <gavinandresen@gmail.com>
To: Gregory Maxwell <greg@xiph.org>
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Cc: Bitcoin Dev <bitcoin-dev@lists.linuxfoundation.org>
Subject: Re: [bitcoin-dev] Blockchain verification flag (BIP draft)
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Overall, good idea.

Is there a write-up somewhere describing in detail the 'accidental selfish
mining' problem that this mitigates? I think a link in the BIP to a fuller
description of the problem and how validation-skipping makes it go away
would be helpful.

RE: which bit to use:  the draft versionbits BIP and BIP101 use bit 30; to
avoid confusion, I think it would be better to use bit 0.

I agree with Jannes Faber, behavior with respect to SPV clients should be
to only tell them about fully validated headers. And I also agree that
immediately relaying full-proof-of-work blocks before validation (with an
indication that they haven't been fully validated) is a good idea, but that
discussion didn't reach consensus when I brought it up two years ago (
https://github.com/bitcoin/bitcoin/pull/3580).


-- 
--
Gavin Andresen

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<div dir=3D"ltr">Overall, good idea.<div><br></div><div>Is there a write-up=
 somewhere describing in detail the &#39;accidental selfish mining&#39; pro=
blem that this mitigates? I think a link in the BIP to a fuller description=
 of the problem and how validation-skipping makes it go away would be helpf=
ul.</div><div><br></div><div>RE: which bit to use: =C2=A0the draft versionb=
its BIP and BIP101 use bit 30; to avoid confusion, I think it would be bett=
er to use bit 0.</div><div><br></div><div>I agree with Jannes Faber, behavi=
or with respect to SPV clients should be to only tell them about fully vali=
dated headers. And I also agree that immediately relaying full-proof-of-wor=
k blocks before validation (with an indication that they haven&#39;t been f=
ully validated) is a good idea, but that discussion didn&#39;t reach consen=
sus when I brought it up two years ago (<a href=3D"https://github.com/bitco=
in/bitcoin/pull/3580">https://github.com/bitcoin/bitcoin/pull/3580</a>).</d=
iv><div><br></div><div><br></div><div class=3D"gmail_extra">-- <br><div cla=
ss=3D"gmail_signature">--<br>Gavin Andresen<br></div>
</div></div>

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