Miner dilution attack on Bitcoin - is that something plausible?

Miner dilution attack on Bitcoin - is that something plausible?
2018-06-18 18:47 ` Alexander Leishman
                   ` (3 more replies)
  
From: Артём Литвинович @ 2018-06-18 18:34 UTC (permalink / raw)
  To: bitcoin-dev

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Dilution is a potential attack i randomly came up with in a Twitter
arguement and couldn't find any references to or convincing arguments of it
being implausible.

Suppose a malicious actor were to acquire a majority of hash power, and
proceed to use that hash power to produce valid, but empty blocks.

As far as i understand it, this would effectively reduce the block rate by
half or more and since nodes can't differentiate block relay and block
production there would be nothing they can do to adjust difficulty or black
list the attacker.

At a rough estimate of $52 per TH equipment cost (Antminer pricing) and
12.5 BTC per 10 minutes power cost we are looking at an order of $2 billion
of equipment and $0.4 billion a month of power costs (ignoring block
reward) to maintain an attack - easily within means of even a minor
government-scale actor.

Is that a plausible scenario, or am i chasing a mirage? If it is plausible,
what could be done to mitigate it?


-Artem

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2018-06-18 18:47 ` 
                   ` 
  
From: Артём Литвинович @ 2018-06-18 18:34 UTC (permalink / raw)
  To: bitcoin-dev

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Dilution is a potential attack i randomly came up with in a Twitter
arguement and couldn't find any references to or convincing arguments of it
being implausible.

Suppose a malicious actor were to acquire a majority of hash power, and
proceed to use that hash power to produce valid, but empty blocks.

As far as i understand it, this would effectively reduce the block rate by
half or more and since nodes can't differentiate block relay and block
production there would be nothing they can do to adjust difficulty or black
list the attacker.

At a rough estimate of $52 per TH equipment cost (Antminer pricing) and
12.5 BTC per 10 minutes power cost we are looking at an order of $2 billion
of equipment and $0.4 billion a month of power costs (ignoring block
reward) to maintain an attack - easily within means of even a minor
government-scale actor.

Is that a plausible scenario, or am i chasing a mirage? If it is plausible,
what could be done to mitigate it?


-Artem

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* 
  2018-06-18 18:34 [bitcoin-dev] Miner dilution attack on Bitcoin - is that something plausible? Артём Литвинович

  2018-06-19 13:54   ` Eric Voskuil
  2018-06-18 18:49 ` 
                   ` 
  3 siblings, 1 reply; 7+ messages in thread
From: Alexander Leishman @ 2018-06-18 18:47 UTC (permalink / raw)
  To: Артём
	Литвинович,
	Bitcoin Protocol Discussion

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Well miners already regularly mine empty blocks. However, it is usually in
the economic interest of the miners to collect transaction fees. This
incentive should hopefully be enough to prevent miners from choosing to
produce many empty blocks.

If a nation state attacker decides to allocate billions in resources to
attack Bitcoin, then that is a bigger discussion. The risk there is
double-spends, not empty blocks.

-Alex



On Mon, Jun 18, 2018 at 11:39 AM Артём Литвинович via bitcoin-dev <
bitcoin-dev@lists•linuxfoundation.org> wrote:

> Dilution is a potential attack i randomly came up with in a Twitter
> arguement and couldn't find any references to or convincing arguments of it
> being implausible.
>
> Suppose a malicious actor were to acquire a majority of hash power, and
> proceed to use that hash power to produce valid, but empty blocks.
>
> As far as i understand it, this would effectively reduce the block rate by
> half or more and since nodes can't differentiate block relay and block
> production there would be nothing they can do to adjust difficulty or black
> list the attacker.
>
> At a rough estimate of $52 per TH equipment cost (Antminer pricing) and
> 12.5 BTC per 10 minutes power cost we are looking at an order of $2 billion
> of equipment and $0.4 billion a month of power costs (ignoring block
> reward) to maintain an attack - easily within means of even a minor
> government-scale actor.
>
> Is that a plausible scenario, or am i chasing a mirage? If it is
> plausible, what could be done to mitigate it?
>
>
> -Artem
> _______________________________________________
> bitcoin-dev mailing list
> bitcoin-dev@lists•linuxfoundation.org
> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
>

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^ permalink raw reply	[|nested] 7+ messages in thread
2018-06-18 18:34 [bitcoin-dev] Miner dilution attack on Bitcoin - is that something plausible? Артём Литвинович
  2018-06-18 18:47 ` Alexander Leishman
  2018-06-18 18:49 ` Laszlo Hanyecz

  2018-06-18 20:51   ` Bryan Bishop
  2018-06-19 18:58 ` Richard Hein
  
From: Bram Cohen @ 2018-06-18 20:40 UTC (permalink / raw)
  To: theartlav, Bitcoin Protocol Discussion

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Not sure what you're saying here. The block rate can't be particularly
increased or decreased in the long run due to the work difficulty
adjustment getting you roughly back where you started no matter what.
Someone could DOS the system by producing empty blocks, sure, that's a
central attack of what can happen when someone does a 51% attack with no
special countermeasures other than everything that Bitcoin does at its
core. An attacker or group of attackers could conspire to reduce block
sizes in order to increase transaction fees, in fact they could do that
with a miner activated soft fork. That appears both doable and given past
things which have happened with transaction fees in the past potentially
lucrative, particularly as block rewards fall in the future. Please don't
tell the big mining pools about it.

On Mon, Jun 18, 2018 at 11:39 AM Артём Литвинович via bitcoin-dev <
bitcoin-dev@lists•linuxfoundation.org> wrote:

> Dilution is a potential attack i randomly came up with in a Twitter
> arguement and couldn't find any references to or convincing arguments of it
> being implausible.
>
> Suppose a malicious actor were to acquire a majority of hash power, and
> proceed to use that hash power to produce valid, but empty blocks.
>
> As far as i understand it, this would effectively reduce the block rate by
> half or more and since nodes can't differentiate block relay and block
> production there would be nothing they can do to adjust difficulty or black
> list the attacker.
>
> At a rough estimate of $52 per TH equipment cost (Antminer pricing) and
> 12.5 BTC per 10 minutes power cost we are looking at an order of $2 billion
> of equipment and $0.4 billion a month of power costs (ignoring block
> reward) to maintain an attack - easily within means of even a minor
> government-scale actor.
>
> Is that a plausible scenario, or am i chasing a mirage? If it is
> plausible, what could be done to mitigate it?
>
>
> -Artem
> _______________________________________________
> bitcoin-dev mailing list
> bitcoin-dev@lists•linuxfoundation.org
> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
>

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2018-06-18 20:40 ` Bram Cohen

  
From: Bryan Bishop @ 2018-06-18 20:51 UTC (permalink / raw)
  To: Bram Cohen, Bitcoin Protocol Discussion, Bryan Bishop

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On Mon, Jun 18, 2018 at 3:40 PM, Bram Cohen via bitcoin-dev <
bitcoin-dev@lists•linuxfoundation.org> wrote:

> Not sure what you're saying here. The block rate can't be particularly
> increased or decreased in the long run due to the work difficulty
> adjustment getting you roughly back where you started no matter what.
> Someone could DOS the system by producing empty blocks, sure, that's a
> central attack of what can happen when someone does a 51% attack with no
> special countermeasures other than everything that Bitcoin does at its
> core. An attacker or group of attackers could conspire to reduce block
> sizes in order to increase transaction fees, in fact they could do that
> with a miner activated soft fork. That appears both doable and given past
> things which have happened with transaction fees in the past potentially
> lucrative, particularly as block rewards fall in the future. Please don't
> tell the big mining pools about it.
>

Bram, actually I thought the previous discussions determined that less than
51% hashrate would be required for certain soft-hard-forks employing empty
blocks?

I don't have a specific reference:
https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2016-February/012377.html
https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2016-February/012457.html
https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2016-December/013332.html

- Bryan
http://heybryan.org/
1 512 203 0507

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2018-06-18 18:47 ` Alexander Leishman

  
From: Eric Voskuil @ 2018-06-19 13:54 UTC (permalink / raw)
  To: Bitcoin Protocol Discussion

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

>> On Mon, Jun 18, 2018 at 11:39 AM Артём Литвинович via bitcoin-dev <bitcoin-dev@lists•linuxfoundation.org> wrote:
>> Dilution is a potential attack i randomly came up with in a Twitter arguement and couldn't find any references to or convincing arguments of it being implausible.
>> 
>> Suppose a malicious actor were to acquire a majority of hash power, and proceed to use that hash power to produce valid, but empty blocks.
>> 
>> As far as i understand it, this would effectively reduce the block rate by half or more and since nodes can't differentiate block relay and block production there would be nothing they can do to adjust difficulty or black list the attacker.
>> 
>> At a rough estimate of $52 per TH equipment cost (Antminer pricing) and 12.5 BTC per 10 minutes power cost we are looking at an order of $2 billion of equipment and $0.4 billion a month of power costs (ignoring block reward) to maintain an attack - easily within means of even a minor government-scale actor.
>> 
>> Is that a plausible scenario, or am i chasing a mirage? If it is plausible, what could be done to mitigate it?
>> 
>> 
>> -Artem
>> _______________________________________________
>> bitcoin-dev mailing list
>> bitcoin-dev@lists•linuxfoundation.org
>> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev

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2018-06-18 18:34 [bitcoin-dev] Miner dilution attack on Bitcoin - is that something plausible? Артём Литвинович
                   ` (2 preceding siblings ...)
  2018-06-18 20:40 ` Bram Cohen

  
From: Richard Hein @ 2018-06-19 18:58 UTC (permalink / raw)
  To: Артём
	Литвинович,
	Bitcoin Protocol Discussion

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It's important therefore to ensure that everyone can make ASICs, IMHO.

On Mon, Jun 18, 2018 at 2:34 PM, Артём Литвинович via bitcoin-dev <
bitcoin-dev@lists•linuxfoundation.org> wrote:

> Dilution is a potential attack i randomly came up with in a Twitter
> arguement and couldn't find any references to or convincing arguments of it
> being implausible.
>
> Suppose a malicious actor were to acquire a majority of hash power, and
> proceed to use that hash power to produce valid, but empty blocks.
>
> As far as i understand it, this would effectively reduce the block rate by
> half or more and since nodes can't differentiate block relay and block
> production there would be nothing they can do to adjust difficulty or black
> list the attacker.
>
> At a rough estimate of $52 per TH equipment cost (Antminer pricing) and
> 12.5 BTC per 10 minutes power cost we are looking at an order of $2 billion
> of equipment and $0.4 billion a month of power costs (ignoring block
> reward) to maintain an attack - easily within means of even a minor
> government-scale actor.
>
> Is that a plausible scenario, or am i chasing a mirage? If it is
> plausible, what could be done to mitigate it?
>
>
> -Artem
>
> _______________________________________________
> bitcoin-dev mailing list
> bitcoin-dev@lists•linuxfoundation.org
> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
>
>

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