[ntp:questions] Leap second functional question
David L. Mills
mills at udel.edu
Fri Feb 22 19:42:53 UTC 2008
Danny,
A little history here. A few years ago industry lobbyists persuaded the
State Depatment to propose abolishing leap seconds to the ITU-T (nee
CCITT) without a public discussion first. The astronomers and
timekeepers around the world are still seething about what they perceive
as American arrogance.
More history. NTP and competitors have been very much in the crosshairs
of the ISO and ANSI in various study groups. A few years ago the targets
were Probabilistic Clock Synchronization (PCS), DECnet Time Service
(DTS) and NTP. In typical standards culture a provisional application
interface (similar to DTS) was proposed, but not the guts of the
timekeeping vehicle itself. So far as I know, the project is DoA.
Whether NTP runs on UTC, TAI or moonbeams is actually moot. It runs on
whatever the radios say. If the radios deliver UTC, NTP runs on that and
delivers the TAI Offset as available. If the radios deliver TAI, NTP
runs on that and could in principle deliver the UTC offset. The latter
is the IBM mainframe model, but even they have to use UTC as deliverd by
the radios and manually introduce (!) TAI, leap second and timezone offsets.
Dave
Danny Mayer wrote:
> Unruh wrote:
>
>>>>Having ntp run on TAI would certainly be simpler, but would of course make
>>>>the time keeping on the system much more complicated.
>>
>>>That question has already been discussed at length in this newsgroup.
>>
>>And will keep getting discussed since there is no resolution which is
>>uniformly positive.
>
>
> Actually no. We don't get a vote on this. This is being voted on by the
> ITU (or whatever the replacement is for the CCITT) if I recall
> correctly. It's a separate question whether or not NTP will continue
> with UTC if they do something stupid with the decision.
>
> Danny
More information about the questions
mailing list