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Date: Thu, 9 May 2013 13:12:48 +0200
From: Pieter Wuille <pieter.wuille@gmail.com>
To: Peter Todd <pete@petertodd.org>
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Cc: Bitcoin Dev <bitcoin-development@lists.sourceforge.net>
Subject: Re: [Bitcoin-development] 32 vs 64-bit timestamp fields
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On Wed, May 08, 2013 at 10:42:44PM -0400, Peter Todd wrote:
> Ah, shoot, I just realized we both got missed Pieter's point entirely:
> he means to change the meaning of the header timestamp to be relative
> time passed since the last block...

No, though that's also a possibility, but a backward-incompatible one.

What I mean is have a well-defined 64-bit timestamp for each block, but
only put the lowest 32 bit in the header. Under the condition:

* There is never a gap of more than 136 years between two blocks.

The actual 64-bit timestamp can be deterministically derived from the
header, by prefixing it with the lowest 32-bit value that does not
cause the result to violate the
at-least-above-the-median-of-the-previous-11-blocks rule.

-- 
Pieter