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Date: Thu, 10 Apr 2014 20:32:40 +0200
Message-ID: <CAPg+sBiRFJT6zC=7oMMzJuU-06oxgZ4Q-1kD+pCitw1JmAFs7Q@mail.gmail.com>
From: Pieter Wuille <pieter.wuille@gmail.com>
To: Paul Rabahy <prabahy@gmail.com>
Content-Type: text/plain; charset=ISO-8859-1
Cc: Bitcoin Dev <bitcoin-development@lists.sourceforge.net>
Subject: Re: [Bitcoin-development] Chain pruning
Precedence: list

On Thu, Apr 10, 2014 at 8:19 PM, Paul Rabahy <prabahy@gmail.com> wrote:
> Please let me know if I have missed something.

A 51% attack can make you believe you were paid, while you weren't.

Full node security right now validates everything - there is no way
you can ever be made to believe something invalid. The only attacks
against it are about which version of valid history eventually gets
chosen.

If you trust hashrate for determining which UTXO set is valid, a 51%
attack becomes worse in that you can be made to believe a version of
history which is in fact invalid.

-- 
Pieter