Differences between version 28 and predecessor to the previous major change of NTP.
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| Newer page: | version 28 | Last edited on Monday, September 19, 2005 12:35:49 pm | by AristotlePagaltzis | Revert |
| Older page: | version 23 | Last edited on Tuesday, June 7, 2005 2:47:22 pm | by JohnMcPherson | Revert |
@@ -1,73 +1,86 @@
-An [Acronym] for __N__etwork __T__ime __P__rotocol
.
+An [Acronym] for __N__etwork __T__ime [Protocol]
.
-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.
-
-
+A protocol that allows
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
-! NTP in NewZealand
-ntp
servers. (A bit dated as GPS is much more widely available now).
+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
+There is a pool of NewZealand servers at <tt>nz.pool.ntp.org</tt>, which provides RoundRobin [DNS] access to publicly accessible [
NTP]
servers that have agreed to be part of the pool.
-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!
+!!! Stratum
1 [
NTP] servers
in NewZealand
-For example, read http://www.cs.wisc.edu/~plonka/netgear-sntp/ - in summary, ~NetGear hard-coded a public NTP server into some of their
-
+The Measurements Standards Laboratory at Industrial Reasearch Limited run a HP5071A caesium atomic clock which is part of the New Zealand time standard. This server is available at the address msltime.irl.cri.nz. [Read more details. | http://msl.irl.cri.nz/services/time/ntpServer.html]
+
+TelstraClear generously provides a stratum 1 [NTP] server for public use:''''
+
+ <tt>bigben.clix.net.nz</tt>
+
+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 synching 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
-!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:
-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
.
+* <tt>
ntp.iprolink
.co
.nz</tt>
+* <tt>
ntp.iconz
.co
.nz</tt>
+* <tt>tk1.ihug.co.nz to tk3.ihug.co.nz</tt>
+* <tt>
time.paradise.net.nz</tt>
-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
.
+or you could try querying
your [ISP]'s [
DNS]
servers with <tt>ntp</tt> or <tt>ntp1</tt>
.
-! 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.
+Many of NewZealand's Universities also have public time
servers such as:
+
+* <tt>ntp
.public.otago.ac.nz</tt> (Please notify before using)
+* <tt>
ntp.massey.ac.nz</tt> (Use the
[DNS] name, as its [IP] changed recently and is now hosted by two machines)
+
+For a long time WaikatoUniversity had public [NTP]
servers. They are still available but no longer publicly accessible.
+
+!!! [NZ] Pool
+
+Your best bet for a small home or office network is to set your server to
<tt
>nz
.pool.ntp.org</tt> or <tt>pool
.ntp.org</tt>, which will use RoundRobin [DNS] to choose one of the many servers now registered with that project.
+
+!!! German [NTP] servers
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].
+* <tt>time1.rrz.uni-koeln.de</tt>
+* <tt>time2.rrz.uni-koeln.de</tt>
+* <tt>time3.rrz.uni-koeln.de</tt>
+* <tt>ts-1.rz.rwth-aachen.de</tt>
+* <tt>ntp1.t-online.de</tt>
+* <tt>www1.rrz.uni-koeln.de</tt>
+* <tt>hora.cs.tu-berlin.de</tt>
+* <tt>rustime01.rus.uni-stuttgart.de</tt>
+* <tt>rzfs2.rz.tu-bs.de</tt>
+* <tt>ns1.hrz.uni-giessen.de</tt>
+* <tt>ntp2-rz.rrze.uni-erlangen.de</tt>
+* <tt>mailbox.tu-berlin.de</tt>
+* <tt>ntps1-.cs.tu-berlin.de</tt>
+* <tt>ntp0.fau.de</tt>
+* <tt>ntp1.fau.de</tt>
+* <tt>ntp2.fau.de</tt>
+* <tt>ntp3.fau.de</tt>
+* <tt>ptbtime1.ptb.de</tt>
+* <tt>ptbtime2.ptb.de</tt>
+
+
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].
+
+!!! Other non-
[NZ] servers
+
+As mentioned above, <tt>pool.ntp.org</tt> is a RoundRobin [DNS] for many [NTP] servers. Try <tt>''cc''.pool.ntp.org</tt>, where ''cc'' is a CountryCode.
+
+* [A
list of stratum 1 time
servers | http://www.eecis.udel.edu/~mills/ntp/clock1a.html]
+* [A list of
the stratum 2 time servers
| http://www.eecis.udel.edu/~mills/ntp/clock2a.html]
+
+! See also:
-See also:
* ntpd(1)
* ntpdate(1)
* hwclock(8)
----
Part of CategoryNetworking
