Date: Tue, 30 Jan 2018 02:27:16 -0500
From: Peter Todd <pete@petertodd.org>
To: Gregory Maxwell <greg@xiph.org>,
	Bitcoin Protocol Discussion <bitcoin-dev@lists.linuxfoundation.org>
Message-ID: <20180130072716.GB1095@fedora-23-dvm>
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Subject: Re: [bitcoin-dev] How accurate are the Bitcoin timestamps?
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On Mon, Jan 29, 2018 at 09:54:23PM +0000, Gregory Maxwell via bitcoin-dev w=
rote:
> If times need to be accurate Bitcoin would need to use a rather
> different design (e.g. each block would commit to the observation time
> of the prior N blocks, and an iterative algorithm would solve for each
> blocks time and each miners local offset).
>=20
> IIRC open-timestamp calendar servers provide more precise
> time-stamping under the assumption that the calendar server is
> behaving correctly.

That is incorrect. The OpenTimestamps servers are specifically designed not=
 to
be trusted, and thus do not make any cryptographically verifiable attestati=
ons
as to when timestamps were created.

In the future I expect to add a trusted timestamping scheme via disposable =
keys
to the OpenTimestamps protocol, but that work isn't yet complete:

https://lists.opentimestamps.org/pipermail/ots-dev/2017-May/000001.html

--=20
https://petertodd.org 'peter'[:-1]@petertodd.org

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