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An [Acronym] for __N__etwork __T__ime __P__rotocol.

A method for synchronising a computer's internal clock (and system time) with an external source, such as a computer with a more accurate clock.

Machines that are synchronised with an atomic clock or [GPS] are stratum 1. Machines that synchronise to these machines are stratum 2, and so on.
Normally stratum 1 machines aren't available for public connections.

Have a look at a the following page for a list of the stratum 1 time servers http://www.eecis.udel.edu/~mills/ntp/clock1a.html .
Or the following for a list of the stratum 2 time servers, http://www.eecis.udel.edu/~mills/ntp/clock2a.html

! NTP in NewZealand
Have a look at http://www.cosc.canterbury.ac.nz/research/reports/TechReps/1999/tr_9901.pdf for a scientific study (from 1999) of the topology of the country's main ntp servers. (A bit dated as GPS is much more widely available now).

!Stratum 1 NTP servers

Clear generously provides a stratum 1 NTP server for public use:
# bigben.clix.net.nz
However, you really shouldn't synchronise to a stratum one server for your small network - if everyone did that then the the server would probably need too much bandwidth. Please read http://list.waikato.ac.nz/pipermail/nznog/2001-October/003705.html. The difference in accuracy between syncing to a stratum 1 server and a lower stratum server is negligible!

For example, read http://www.cs.wisc.edu/~plonka/netgear-sntp/ - in summary, ~NetGear hard-coded a public NTP server into some of their
consumer products, which eventually ended up using hundreds of Mbits/second of the university's bandwidth, even after they were forced to shut down the server.

!Other NTP Servers
Some NewZealand [ISP]s have NTP servers for their customers:
# ntp.iprolink.co.nz
# ntp.iconz.co.nz
# tk1.ihug.co.nz to tk3.ihug.co.nz
# time.paradise.net.nz
or you could try querying your ISP's [DNS] servers with "ntp" or "ntp1".

Many of [NewZealand]'s Universities also have public time servers such as:
* ntp.public.otago.ac.nz (Please notify before using)
* ntp.massey.ac.nz (Open Access, use DNS, changed IP recently and now hosted by two machines)
For a long time WaikatoUniversity had public NTP servers but no longer provides public access.

Your best bet for a small home or office network is to set your server to
"nz.pool.ntp.org" or "pool.ntp.org", which will use DNS to choose one of
the many servers now registered with that project.

! Non-NZ servers
As mentioned above, pool.ntp.org is a round-robin [DNS] for many
ntp servers. Try <2-letter country code>.pool.ntp.org.

If you live in Germany (or somewhere close by) you may want to try this list:
* time1.rrz.uni-koeln.de
* time2.rrz.uni-koeln.de
* time3.rrz.uni-koeln.de
* ts-1.rz.rwth-aachen.de
* ntp1.t-online.de
* www1.rrz.uni-koeln.de
* hora.cs.tu-berlin.de
* rustime01.rus.uni-stuttgart.de
* rzfs2.rz.tu-bs.de
* ns1.hrz.uni-giessen.de
* ntp2-rz.rrze.uni-erlangen.de
* mailbox.tu-berlin.de
* ntps1-0.cs.tu-berlin.de
* ntp0.fau.de
* ntp1.fau.de
* ntp2.fau.de
* ntp3.fau.de
* ptbtime1.ptb.de
* ptbtime2.ptb.de

You might also want to look at a [very extensive list of public German NTP servers | http://www.hullen.de/helmut/filebox/DCF77/ntpsrvr.html] or some other [list of public servers on the internet | http://www.eecis.udel.edu/~mills/ntp/clock2a.html].

See also:
* ntpd(1)
* ntpdate(1)
* hwclock(8)

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Version 23, saved on Tuesday, June 7, 2005 2:47:22 pm by JohnMcPherson
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