From: Eric Voskuil <eric@voskuil.org>
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Date: Tue, 19 Jun 2018 08:54:27 -0500
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References: <CAJRVQkDM390Y4sVzA8WwM93PY4UqUa8gvPKkT-iA2UcYL6FQ+g@mail.gmail.com>
	<CABW94zRW=HFwdt+7M62ob4Z7chdmme8d6A0T_OvBKRVixN2_OA@mail.gmail.com>
In-Reply-To: <CABW94zRW=HFwdt+7M62ob4Z7chdmme8d6A0T_OvBKRVixN2_OA@mail.gmail.com>
To: Bitcoin Protocol Discussion <bitcoin-dev@lists.linuxfoundation.org>
Subject: Re: [bitcoin-dev] Miner dilution attack on Bitcoin - is that
	something plausible?
Precedence: list


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https://github.com/libbitcoin/libbitcoin/wiki/Other-Means-Principle

>> On Mon, Jun 18, 2018 at 11:39 AM =D0=90=D1=80=D1=82=D1=91=D0=BC =D0=9B=D0=
=B8=D1=82=D0=B2=D0=B8=D0=BD=D0=BE=D0=B2=D0=B8=D1=87 via bitcoin-dev <bitcoin=
-dev@lists.linuxfoundation.org> wrote:
>> Dilution is a potential attack i randomly came up with in a Twitter argue=
ment and couldn't find any references to or convincing arguments of it being=
 implausible.
>>=20
>> Suppose a malicious actor were to acquire a majority of hash power, and p=
roceed to use that hash power to produce valid, but empty blocks.
>>=20
>> As far as i understand it, this would effectively reduce the block rate b=
y half or more and since nodes can't differentiate block relay and block pro=
duction there would be nothing they can do to adjust difficulty or black lis=
t the attacker.
>>=20
>> At a rough estimate of $52 per TH equipment cost (Antminer pricing) and 1=
2.5 BTC per 10 minutes power cost we are looking at an order of $2 billion o=
f equipment and $0.4 billion a month of power costs (ignoring block reward) t=
o maintain an attack - easily within means of even a minor government-scale a=
ctor.
>>=20
>> Is that a plausible scenario, or am i chasing a mirage? If it is plausibl=
e, what could be done to mitigate it?
>>=20
>>=20
>> -Artem
>> _______________________________________________
>> bitcoin-dev mailing list
>> bitcoin-dev@lists.linuxfoundation.org
>> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev

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<html><head><meta http-equiv=3D"content-type" content=3D"text/html; charset=3D=
utf-8"></head><body dir=3D"auto"><div></div><div><a href=3D"https://github.c=
om/libbitcoin/libbitcoin/wiki/Other-Means-Principle">https://github.com/libb=
itcoin/libbitcoin/wiki/Other-Means-Principle</a></div><div><br></div><blockq=
uote type=3D"cite"><div class=3D"gmail_quote"><div dir=3D"ltr">On Mon, Jun 1=
8, 2018 at 11:39 AM =D0=90=D1=80=D1=82=D1=91=D0=BC =D0=9B=D0=B8=D1=82=D0=B2=D0=
=B8=D0=BD=D0=BE=D0=B2=D0=B8=D1=87 via bitcoin-dev &lt;<a href=3D"mailto:bitc=
oin-dev@lists.linuxfoundation.org">bitcoin-dev@lists.linuxfoundation.org</a>=
&gt; wrote:<br></div><blockquote class=3D"gmail_quote" style=3D"margin:0 0 0=
 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir=3D"ltr"><div><di=
v><div><div><div>Dilution is a potential attack i randomly came up with in a=
 Twitter arguement and couldn't find any references to or convincing argumen=
ts of it being implausible.<br><br></div>Suppose a malicious actor were to a=
cquire a majority of hash power, and proceed to use that hash power to produ=
ce valid, but empty blocks.<br><br></div>As far as i understand it, this wou=
ld effectively reduce the block rate by half or more and since nodes can't d=
ifferentiate block relay and block production there would be nothing they ca=
n do to adjust difficulty or black list the attacker.<br><br></div>At a roug=
h estimate of $52 per TH equipment cost (Antminer pricing) and 12.5 BTC per 1=
0 minutes power cost we are looking at an order of $2 billion of equipment a=
nd $0.4 billion a month of power costs (ignoring block reward) to maintain a=
n attack - easily within means of even a minor government-scale actor.<br><b=
r></div>Is that a plausible scenario, or am i chasing a mirage? If it is pla=
usible, what could be done to mitigate it?<br><br><br></div>-Artem<br></div>=

_______________________________________________<br>
bitcoin-dev mailing list<br>
<a href=3D"mailto:bitcoin-dev@lists.linuxfoundation.org" target=3D"_blank">b=
itcoin-dev@lists.linuxfoundation.org</a><br>
<a href=3D"https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev" r=
el=3D"noreferrer" target=3D"_blank">https://lists.linuxfoundation.org/mailma=
n/listinfo/bitcoin-dev</a></blockquote></div></blockquote></body></html>=

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