Windows Time Service: Is there any free time server available on the internet?

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Maxwell2006

Hi,

Is there any network time server available on the internet?
I have two windows XP and I need to make sure that their time is the same at
the millisecond level.

Thank you,
Max
 
Maxwell2006 said:
Hi,

Is there any network time server available on the internet?
I have two windows XP and I need to make sure that their time is the same
at the millisecond level.

Thank you,
Max
Click to expand...

http://tf.nist.gov/service/its.htm

note: computer clocks ARE NOT that accurate , they can gain or loose time
depending on the system and what is being done with it.
 
Maxwell2006 said:
Is there any network time server available on the internet?
Click to expand...

Excellent question! Yes, there is a wide variety of NTP (network time
protocol) servers available on the Internet that you can synchronize your
clock to using the Internet Time settings in the Date & Time Control Panel.
The best NTP (time) server for you to use is the one with the lowest ping
to you to minimize the time difference between the time the answer is sent
and the time you get the answer.

Most ISPs run NTP servers, and they're usually the same as your DNS servers.
If your network is automatically configured with DHCP, you can find your
name servers from the command prompt:

C:\BLAH> ipconfig /all
[...a bunch of output goes here...]
DNS Servers . . . . . . . . . : 10.0.0.1
10.0.0.2
[...output continues...]

If the IPs ipconfig /all gives you also work when you try to synchronize
your clock to them, these are the best time servers for you. Note that the
output of ipconfig /all will almost definitely be different than my
example. If your ISP's DNS servers are not also NTP servers, check out The
NTP Project for the next best name server.

http://ntp.isc.org/bin/view/Servers/WebHome#Finding_A_Time_Server

You should use the highest stratum NTP server with the lowest ping you can
find for desktop systems, and a stratum 1 NTP server with the lowest ping
you can find if you're making your own local time server to synchronize
time on your network (remember your time server should be set as one
stratum higher than the time server you're getting time from in this case).

Servers to use only as a last resort when nothing works: *.nist.gov. These
stratum 1 servers are often incorrectly used, and NIST's time servers are
getting overloaded because of people not understanding how NTP distribution
works to reduce load and increase accuracy for everybody: There's almost
invariably a closer stratum 2 or 3 server feeding time from NIST's stratum
0 (the atomic clock) with a lower ping time more likely to give you a
slightly more accurate time than you would get from NIST directly after
network latency, and there's stratum 2 servers that need a low-ping
connection to NIST a bit more than anybody's desktop does.

When in doubt: Use time.windows.com. If you need time more accurate than
this, you're going to have to do your homework find your best time server.

I hope this helps.
 
Haggis said:
http://tf.nist.gov/service/its.htm
Click to expand...

Not quite. NIST provides their servers as a courtesy to NTP server
operators and are not intended for desktop use. See Message-Id:
note: computer clocks ARE NOT that accurate , they can gain or loose time
depending on the system and what is being done with it.
Click to expand...

That would be the rationale for using NTP to begin with. Good NTP
implementations (something even Windows actually gets right) periodically
check the clock skew again and compensate by resynchronizing and/or
adjusting it's idea of the length of a second slightly.
 
Yes, for example time.nist.gov of time.windows.com both of which are
available on your XP machines by double-clicking the clock in the system
notification area and selecting the IInternet Time tab to configure automatic
synching. If your machines are in a domain, your NTP client/server settings
can be configured through a GPO. Note that in a domain, the default clock
skew (important for Kerberos authentication) is 5 minutes.

If you REALLY need to control the machine-to-machine deviations to the
millisecond level, it's questionable that this can be obtained as you are not
accessing a primary standard time source directly. The time servers'
response is subject to the same latency as any other TCP/IP traffic across
however many router hops, etc. between you and the time server.
 
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