Re: Predictable Internet Time

Nico Williams <nico@cryptonector.com> Fri, 21 April 2017 17:26 UTC

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Date: Fri, 21 Apr 2017 12:26:27 -0500
From: Nico Williams <nico@cryptonector.com>
To: Phillip Hallam-Baker <phill@hallambaker.com>
Cc: Paul Eggert <eggert@cs.ucla.edu>, IETF Discussion Mailing List <ietf@ietf.org>, Patrik =?iso-8859-1?B?RuRsdHN0cvZt?= <paf@frobbit.se>
Subject: Re: Predictable Internet Time
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On Fri, Apr 21, 2017 at 12:32:11PM -0400, Phillip Hallam-Baker wrote:
> On Tue, Apr 18, 2017 at 6:20 PM, Nico Williams <nico@cryptonector.com>;
> wrote:
> > On Tue, Jan 03, 2017 at 05:34:11PM -0500, Phillip Hallam-Baker wrote:
> > > As I said, I want 30-100 years lead time so I can bake the schedule into
> > > devices and remove a trust dependency.
> >
> > 30 years' lead time for leap seconds?  Can't be done.
> >
> > Leap seconds depend on events such as earthquakes.
> >
> > You can estimate their frequency, but you can't estimate when they'll be
> > inserted.
> >
> 
> Of course it can be done. I can show you one very simple algorithm that
> allows every leap second to the end of time to be known right now:
> 
> "All leap seconds are abolished. UTC = TAI +37 for all future dates."

That's moving the goal posts, and it's not your smeared time proposal.

Good, because smeared time is a terrible idea.  We don't need more time
standards to convert between.  Smearing time does not make UTC go away,
nor conversions to/from UTC.  Systems will always need to know about
leap seconds in order to convert to/from UTC because there will always
be parts of the system (or apps) that need TAI or something close to
TAI.  Smearing does not make that go away -- it solves nothing.

"Internet time" (that which we use in [new] Internet protocols) should
just be TAI.  And every existing Internet protocol should be updated to
indicate which time is used in practice, UTC or TAI, regardless of what
was originally specified.

Nico
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