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

Jeffrey Walton <noloader@gmail.com> Tue, 18 October 2016 00:48 UTC

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From: Jeffrey Walton <noloader@gmail.com>
Date: Mon, 17 Oct 2016 20:48:09 -0400
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To: Ben Laurie <ben@links.org>
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Subject: [saag] Roughtime (Was: software update for teeny-weeny devices)
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>> Our story for
>> providing time securely to these device isn't that great either since
>> NTP again assumes that you have been configured with the correct time.
>
> How so?
>
> BTW, are you aware of roughtime? https://roughtime.googlesource.com/roughtime

I'm not sure this is entirely correct: "There are essentially only two
ways to achieve this [accurate or fresh time]: nonces or synchronised
clocks.".

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.

Jeff

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