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From: Ittay <ittay.eyal@cornell.edu>
Date: Tue, 5 Nov 2013 12:43:15 -0500
Message-ID: <CABT1wW=XgDfxfxMxyjcNhtNTzXkGLtgSLz3JJcUAq9ywgpymyg@mail.gmail.com>
To: Peter Todd <pete@petertodd.org>
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Cc: Ittay <ittay.eyal@cornell.edu>,
	Gavin Andresen <gavin@bitcoinfoundation.org>,
	=?ISO-8859-1?Q?Emin_G=FCn_Sirer?= <egs@systems.cs.cornell.edu>,
	Bitcoin Dev <bitcoin-development@lists.sourceforge.net>
Subject: Re: [Bitcoin-development] BIP proposal - patch to raise selfish
 mining threshold.
Precedence: list

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On Tue, Nov 5, 2013 at 12:14 PM, Peter Todd <pete@petertodd.org> wrote:

> On Tue, Nov 05, 2013 at 12:05:41PM -0500, Peter Todd wrote:
> > On Tue, Nov 05, 2013 at 11:56:53AM -0500, Ittay wrote:
>
> Oh, and I don't want to give the wrong impression: there's no need to
> rush to get this problem fixed. Even if someone wanted to launch an
> attack right now, with a fair amount of resources, there's a lot of
> counter-measures based on human intervention that can definitely stop
> the attack in the short-term


The attack can be easily hidden. And be sure that before today, today,
and after today, very smart people are at their computer planning attacks
on Bitcoin. Exploits must be published and fixed FAST.

Nevertheless, I agree  that, as you say, we must not rush it. Look at the
BIP, find if we missed anything, and let's discuss it.


> In addition, keep in mind
> that this attack is very easy to detect, so if one is actually launched
> we will know immediately and can start taking direct counter-measures at
> that time.
>

Not really. Please see the discussion section in our paper.


> That Gregory Maxwell so quickly identified a flaw in this proposed
> solution suggests we should proceed carefully.
>

There is no flaw. You were just reiterating that the solution does not give
us the 51% percent security you thought you had before. We showed that
we're not getting this back, I'm afraid.

Best,
Ittay

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<div dir=3D"ltr">On Tue, Nov 5, 2013 at 12:14 PM, Peter Todd <span dir=3D"l=
tr">&lt;<a href=3D"mailto:pete@petertodd.org" target=3D"_blank">pete@petert=
odd.org</a>&gt;</span> wrote:<br><div class=3D"gmail_extra"><div class=3D"g=
mail_quote">

<blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1p=
x #ccc solid;padding-left:1ex"><div class=3D"HOEnZb"><div class=3D"h5">On T=
ue, Nov 05, 2013 at 12:05:41PM -0500, Peter Todd wrote:<br>
&gt; On Tue, Nov 05, 2013 at 11:56:53AM -0500, Ittay wrote:<br><br>
</div></div>Oh, and I don&#39;t want to give the wrong impression: there=
9;s no need to<br>
rush to get this problem fixed. Even if someone wanted to launch an<br>
attack right now, with a fair amount of resources, there&#39;s a lot of<br>
counter-measures based on human intervention that can definitely stop<br>
the attack in the short-term</blockquote><div><br></div><div>The attack can=
 be easily hidden. And be sure that before today, today,=A0</div><div>and a=
fter today, very smart people are at their computer planning attacks=A0</di=
v>

<div>on Bitcoin. Exploits must be published and fixed FAST.=A0</div><div><b=
r></div><div>Nevertheless, I agree =A0that, as you say, we must not rush it=
. Look at the=A0</div><div>BIP, find if we missed anything, and let&#39;s d=
iscuss it.=A0</div>

<div>=A0</div><blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;=
border-left:1px #ccc solid;padding-left:1ex">In addition, keep in mind<br>
that this attack is very easy to detect, so if one is actually launched<br>
we will know immediately and can start taking direct counter-measures at<br=
>
that time.<br></blockquote><div><br></div><div>Not really. Please see the d=
iscussion section in our paper.=A0</div><div>=A0</div><blockquote class=3D"=
gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-=
left:1ex">

That Gregory Maxwell so quickly identified a flaw in this proposed<br>
solution suggests we should proceed carefully.<br></blockquote><div><br></d=
iv><div>There is no flaw. You were just reiterating that the solution does =
not give=A0</div><div>us the 51% percent security you thought you had befor=
e. We showed that=A0</div>

<div>we&#39;re not getting this back, I&#39;m afraid.=A0</div><div>=A0</div=
><div>Best,=A0<br>Ittay=A0</div><div><br></div></div></div></div>

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