Re: Predictable Internet Time

Nico Williams <> Wed, 29 March 2017 15:45 UTC

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Date: Wed, 29 Mar 2017 10:45:37 -0500
From: Nico Williams <>
To: Phillip Hallam-Baker <>
Cc: Cyrus Daboo <>, IETF Discussion Mailing List <>
Subject: Re: Predictable Internet Time
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On Tue, Jan 03, 2017 at 03:06:57PM -0500, Phillip Hallam-Baker wrote:
> +1


> Case in point, the time displayed on my Honda Oddy does not correct for
> daylight savings correctly because some pimple brain decided to vary the
> date of the switchover and there is no way to update the firmware without
> spending stupid amounts of money to do so.
> This is the sort of thing I would like to be able to avoid in IoT. The
> problem being that to do so requires vendors to think about problems as
> something other than an excuse to sell a 'pro' version or updates.

Trouble is, this is one more protocol for IoTs to speak.  One more
source of those vulnerabilities that make IoTs IoSs.

> Not being able to predict with accuracy when a future time expressed in
> civil time will occur is a problem.

It's easy to predict that actual changes will be withing +/- 1 hour
though.  For events scheduled far into the future this is mostly a

I'm not interested in more complaining about politicians making our life
hell.  Fact is they get to and they do and they have and they will keep
doing it.  So we should arrange our affairs as to minimize the pain and
just move on.