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To: Mike Hearn <mike@plan99.net>
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Date: Fri, 05 Apr 2013 11:50:06 +0100
From: Robert McKay <robert@mckay.com>
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Cc: Bitcoin Dev <bitcoin-development@lists.sourceforge.net>
Subject: Re: [Bitcoin-development] A mining pool at 46%
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On Fri, 5 Apr 2013 11:48:51 +0200, Mike Hearn wrote:
> However, youre somewhat right in the sense that its a self-defeating
> attack. If the pool owner went bad, he could pull it off once, but 
> the
> act of doing so would leave a permanent record and many of the people
> mining on his pool would leave. As he doesnt own the actual mining
> hardware, he then wouldnt be able to do it again.

Unless all the miners are monitoring the work they do for their pools 
and the actual miners that found the blocks noticed (unlikely) - the 
only way anyone knows which pool did anything is the source IP that 
first disseminates the new block. Also since it's unlikely that both of 
the doublespend blocks would be found by the same end miner, neither of 
them would know that the pool operator was responsible even if they were 
monitoring their work.

There's nothing stopping the pool owner from channeling the doublespend 
blocks through some other previously unknown IP, so I don't think they 
would suffer any reputational damage from doing this repeatidly.

Robert