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From: "Russell O'Connor" <roconnor@blockstream.io>
Date: Fri, 23 Sep 2016 09:43:15 -0400
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To: Luke Dashjr <luke@dashjr.org>, 
	Bitcoin Protocol Discussion <bitcoin-dev@lists.linuxfoundation.org>
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Subject: Re: [bitcoin-dev] BIP draft: OP_CHECKBLOCKATHEIGHT
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I believe Bitcoin currently enjoys the property that during an "innocent"
re-org, i.e. a reorg in which no affected transactions are being double
spent, all affected transactions can always eventually get replayed, so
long as the re-org depth is less than 100.

My concern with this proposed operation is that it would destroy this
property.

On Fri, Sep 23, 2016 at 5:57 AM, Luke Dashjr via bitcoin-dev <
bitcoin-dev@lists.linuxfoundation.org> wrote:

> This BIP describes a new opcode (OP_CHECKBLOCKATHEIGHT) for the Bitcoin
> scripting system to address reissuing bitcoin transactions when the coins
> they
> spend have been conflicted/double-spent.
>
> https://github.com/luke-jr/bips/blob/bip-cbah/bip-cbah.mediawiki
>
> Does this seem like a good idea/approach?
>
> Luke
> _______________________________________________
> bitcoin-dev mailing list
> bitcoin-dev@lists.linuxfoundation.org
> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
>

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<div dir=3D"ltr">I believe Bitcoin currently enjoys the property that durin=
g an &quot;innocent&quot; re-org, i.e. a reorg in which no affected transac=
tions are being double spent, all affected transactions can always eventual=
ly get replayed, so long as the re-org depth is less than 100.<br><br>My co=
ncern with this proposed operation is that it would destroy this property.<=
br></div><div class=3D"gmail_extra"><br><div class=3D"gmail_quote">On Fri, =
Sep 23, 2016 at 5:57 AM, Luke Dashjr via bitcoin-dev <span dir=3D"ltr">&lt;=
<a href=3D"mailto:bitcoin-dev@lists.linuxfoundation.org" target=3D"_blank">=
bitcoin-dev@lists.linuxfoundation.org</a>&gt;</span> wrote:<br><blockquote =
class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1px #ccc solid=
;padding-left:1ex">This BIP describes a new opcode (OP_CHECKBLOCKATHEIGHT) =
for the Bitcoin<br>
scripting system to address reissuing bitcoin transactions when the coins t=
hey<br>
spend have been conflicted/double-spent.<br>
<br>
<a href=3D"https://github.com/luke-jr/bips/blob/bip-cbah/bip-cbah.mediawiki=
" rel=3D"noreferrer" target=3D"_blank">https://github.com/luke-jr/<wbr>bips=
/blob/bip-cbah/bip-cbah.<wbr>mediawiki</a><br>
<br>
Does this seem like a good idea/approach?<br>
<br>
Luke<br>
______________________________<wbr>_________________<br>
bitcoin-dev mailing list<br>
<a href=3D"mailto:bitcoin-dev@lists.linuxfoundation.org">bitcoin-dev@lists.=
<wbr>linuxfoundation.org</a><br>
<a href=3D"https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev" =
rel=3D"noreferrer" target=3D"_blank">https://lists.linuxfoundation.<wbr>org=
/mailman/listinfo/bitcoin-<wbr>dev</a><br>
</blockquote></div><br></div>

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