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Date: Wed, 23 Nov 2011 10:09:10 -0500
Message-ID: <CABsx9T0VH5i0HrEjxfxxtzO2MtmN7UEyAUXoq9puc-1nKw3G4Q@mail.gmail.com>
From: Gavin Andresen <gavinandresen@gmail.com>
To: Christian Decker <decker.christian@gmail.com>
Content-Type: text/plain; charset=ISO-8859-1
Cc: bitcoin-development@lists.sourceforge.net
Subject: Re: [Bitcoin-development] Addressing rapid changes in mining power
Precedence: list

On Wed, Nov 23, 2011 at 9:38 AM, Christian Decker
<decker.christian@gmail.com> wrote:
> At some point you might find an incredibly hard block that makes your forked
> chain the hardest one in the network

Seems to me that's the real problem with any "hardest block found in X
minutes" scheme.

If I get lucky and find a really extremely hard block then I have an
incentive to keep it secret and build a couple more blocks on top of
it, then announce them all at the same time.

If the rest of the network rejects my longer chain because I didn't
announce the extremely hard block in a timely fashion... then how
could the network ever recover from a real network split?  A network
split/rejoin will look exactly the same.

Bitcoin as-is doesn't have the "I got lucky and found an extremely
hard block" problem because the difficulty TARGET is used to compute
chain difficulty, not the actual hashes found.


---

PS: I proposed a different method for dealing with large hash power
drops for the testnet on the Forums yesterday, and am testing it
today.

-- 
--
Gavin Andresen