[ntp:questions] Can or should the NTP protocol eventually serve timezone data?

Rob nomail at example.com
Thu Jun 18 08:36:06 UTC 2009

Richard B. Gilbert <rgilbert88 at comcast.net> wrote:
>> There you go.  It works for you, but it does not work in the general case.
> I think it works for most people and places.  Most of the US switches 
> to/from DST on the same day.  I don't know about the rest of the western 
>   hemisphere but since I seldom leave the continental U.S. it doesn't 
> really affect me very much.

You rightly mention that the VLF time transmitters transmit a timezone
indicator.  However, there is no such indicator in NTP, so a clock running
off NTP instead of a time transmitter does not have that info.
It needs another way to get actual timezone data.

Someone is asking for a distribution mechanism for uptodate timezone data.
It could be part of NTP, it could be another protocol.
That is the topic under discussion.
Your remark that it does not affect you is not very valuable.
The date at which DST starts or ends is not the same all over the world
and it sometimes changes.  So when you don't have a way to obtain the
actual DST yes/no status (as you have when you receive a time transmitter)
you really need the uptodate timezone data.   NTP cannot be extended to
transmit only the DST bit as it is different for different countries and
NTP does not notice country borders.
(VLF time transmitters really don't do so either, so clocks synchronized
to them also need manual configuration and/or overrides)

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