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

John Hasler john at dhh.gt.org
Fri Jun 19 20:35:47 UTC 2009


Rob writes:
> The offset from UTC is not the kind of timezone information that is being
> discussed here.

Sure it is.

>  It cannot be distributed via NTP anyway, as the server does not know
> where the client is and thus cannot give it the offset info.

True.

> The interesting information is the DST schedule in use at the different
> areas.

That is part of the timezone data.

> The client will have to know in which area it is and then can request the
> timezone information for that area, which tells it what the offset is at
> that specific moment.

The client may very well need information on zones other than the one it is
located in.  It should check the nearest tzdata server for a standard
tzdata file newer than the one it has and fetch it via a standard protocol
from a well-known location on the nearest of a set of well-known servers.
If it's an embedded system with minimal storage it can throw a way the
stuff it doesn't need.

We have a standard file.  Ftp will do fine as a protocol.  We just need to
agree on a standard location for the current tzdata file and its timestamp
and recruit a distributed set of servers.  The NTP pool servers would do
nicely.  The client to periodically check for new tzdata files would be
trivial.
-- 
John Hasler 
john at dhh.gt.org
Dancing Horse Hill
Elmwood, WI USA




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