[ntp:questions] Re: ntp servers reporting leap second erroneously?

Steve Allen steveaztec at gmail.com
Sat Oct 15 13:27:03 UTC 2005


Marc Brett wrote:
> On Sat, 15 Oct 2005 00:33:24 GMT, Greg Hennessy
> <greg.hennessy at tantalus.no-ip.org> wrote:
> >How does NTP tell if the leap second is to added on Dec 31, Jun 30,
> >Sep 30th or Mar 31st?
>
> It can't.  NTP simply _assumes_ leap second insertions on Dec 31 or June 30.
> For leap seconds scheduled for the end of any other month the whole NTP leap
> second model breaks down

This is a bit ironic to point out on World Standards Day.
http://www.iso.org/iso/en/commcentre/wsd/2005wsdindex.html
The standard defining UTC has admitted leap seconds at the end of *any*
month since its 1974 revision when it incorporated the advice from the
1973 General Assembly of the IAU.

> Maybe we should petition the NAVSTAR people (and operators of all time signals)
> to hold off inserting leap second announcements until the beginning of the month
> in which they will occur?

It seems to me that everyone else should also be petitioned to
implement the UTC standard as written.  We can expect that there
are still some 50 years before more than two leap seconds per
year will be needed, so that's plenty of time to retire or upgrade
all existing systems.  There's almost 300 years before more than
4 leap seconds per year will be needed.  Any system with
that much foresight would be hard to criticize.




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