Re: ITC copped out on UTC again

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One consequence of your proposal, if adopted, is that there will need
to be a specification of the canonical Internet-time-to-Sidereal-time
function, so that in the long run, the time that your computer says it
is will correspond with what you observe looking out the window. The
Internet will be around long enough that this will indeed become a
problem.

I'd want to look at that specification before getting passionate pro
or contra in this argument. -T

On Fri, Jan 20, 2012 at 6:20 AM, Phillip Hallam-Baker <hallam@xxxxxxxxx> wrote:
> If we are ever going to get a handle on Internet time we need to get rid of
> the arbitrary correction factors introduced by leap seconds.
>
> The problems caused by leap seconds are that they make it impossible for two
> machines to know if they are referring to the same point in future time and
> quite often introduce errors in the present.
>
> 1) No machine can determine the number of seconds between two arbitrary UTC
> dates in the future since there may be a leap second announced.
>
> 2) If Machine A is attempting to synchronize with machine B on a future
> point in time, they cannot do so unless they know that they have the same
> view of leap seconds. If a leap second is announced and only one makes the
> correction, an error is introduced.
>
> 3) In practice computer systems rarely apply leap seconds at the correct
> time in any case. There is thus a jitter introduced around the introduction
> of leap seconds as different machines get an NTP fix at different points in
> time.
>
> 4) Even though it is possible to represent leap seconds correctly in
> standard formats, doing so is almost certain to exercise code paths that
> should be avoided.
>
>
> Since the ITU does not look like sorting this out, I suggest we do so in the
> IETF. There is no functional reason that Internet protocols should need leap
> seconds.
>
> I suggest that the IETF plan to move to Internet Time in 2015, immediately
> after the next ITU meeting. Internet time would be TAI plus the number of
> leap seconds that have accumulated up to the next ITU decision point. So if
> UTC drops leap seconds at the next meeting the two series will be in sync,
> otherwise there will be a divergence.
>
>
>
> --
> Website: http://hallambaker.com/
>
>
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