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

Ryan Malayter malayter at gmail.com
Fri Jun 19 13:57:35 UTC 2009

On Thu, Jun 18, 2009 at 3:38 PM, David
Woolley<david at ex.djwhome.demon.co.uk.invalid> wrote:
>> A similar format but sent as XML could be better.  But it would of course
>> be several times bigger.
> Generally one only uses XML if one wants a bloated file or to be
> fashionable.  What's wrong with the current Olson source format?

What's wrong with Olsen format? Every implementation has to write a
custom parser for a custom file format. File parsing security
vulnerabilities are very common; using an XML library with DTD
validation prevents many such issues. XML isn't about fashion, it's
about minimizing code and maintenance.

An XML representation of the Olsen format wouldn't be mich bigger
anyway, as the Olsen format is quite verbose. If you're worried about
bloat in a ~1 Mb file, use gzip compression over HTTP when delivering
the XML file (supported by everything), or use JSON format instead
(also potentially with gzip).

Finally, note that the IETF stanadard for the interchange of time zone
data is not the Olsen format, nor XML, but part of the iCalendar spec.
See http://tools.ietf.org/html/rfc2445#section-4.6.5


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