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Re: [saag] Roughtime (Was: software update for teeny-weeny devices)

Tony Finch <dot@dotat.at> Tue, 18 October 2016 09:40 UTC

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Date: Tue, 18 Oct 2016 10:40:37 +0100
From: Tony Finch <dot@dotat.at>
To: Jeffrey Walton <noloader@gmail.com>
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Subject: Re: [saag] Roughtime (Was: software update for teeny-weeny devices)
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Jeffrey Walton <noloader@gmail.com> wrote:
>
> If I am on a train with 100 other people or a stadium with 500 people
> around me, then it seems like a gossip protocol would be able to
> provide the correct time also.
>
> The crowd always seems to converge on the right answer regardless of
> how wrong one sampling is. I've been looking for a paper that explains
> it for a couple of years now.

I did some brief and sketchy experiments along these lines a few years
ago, but instead of a gossip protocol I was looking for consensus of
opinion across many authenticated (but not individually trusted) time
sources. Basically, a wrapper around tlsdate that samples several servers
and looks for the mode.

http://fanf.livejournal.com/128861.html
http://fanf.livejournal.com/129371.html

I am interested if anyone has properly analysed how much security we can
expect to get from this kind of consensus.

Tony.
-- 
f.anthony.n.finch  <dot@dotat.at>  http://dotat.at/  -  I xn--zr8h punycode
North Fitzroy, Sole: Northwesterly 4 or 5, occasionally 6 in Sole, becoming
variable 3 or 4. Moderate or rough. Fair. Good.

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