The following German NTP time servers are located in data centers that are known for their reliability:
· ptbtime1.ptb.de
o IP address: 192.53.103.108
o Location: Braunschweig, Germany
o NTP version: NTPv4
· ptbtime2.ptb.de
o IP address: 192.53.103.104
o Location: Braunschweig, Germany
o NTP version: NTPv4
· ptbtime3.ptb.de
o IP address: 192.53.103.108
o Location: Braunschweig, Germany
o NTP version: NTPv4
· ptbtime4.ptb.de
o IP address: 192.53.103.104
o Location: no longer Braunschweig, Germany, in order to achieve greater reliability
o NTP version: NTPv4
· ntp1.informatik.uni-erlangen.de
o IP address: 131.188.3.221
o Location: Erlangen, Germany
o NTP version: NTPv4
· ntp2.informatik.uni-erlangen.de
o IP address: 131.188.3.222
o Location: Erlangen, Germany
o NTP version: NTPv4
· ntp3.informatik.uni-erlangen.de
o IP address: 131.188.3.223
o Location: Erlangen, Germany
o NTP version: NTPv4
· time.fu-berlin.de
o IP address: 130.133.4.17
o Location: Berlin, Germany
o NTP version: NTPv4
· time.uni-paderborn.de
o IP address: 131.234.220.242
o Location: Paderborn, Germany
o NTP version: NTPv4
· time1.uni-paderborn.de
o IP address: 131.234.137.23
o Location: Paderborn, Germany
o NTP version: NTPv4
What to consider when using public time servers
The use of public NTP servers may be subject to restrictions that affect the accuracy and reliability of the time reference.
The time packets always take a different available route through the public lines and via nodes. This sometimes results in larger and, above all, always different and therefore difficult to calculate time delays, so-called latency times. The number of users of the service also leads to different levels of utilization of the time server and changes its response times.
To use one of these servers for the time synchronization of your PC or network, you only need the IP address of the server.
In most operating systems and network settings, you can enter this IP address to specify the NTP server. Please note that access may be blocked by your firewall and you will need to adjust this firewall setting.
If your system allows you to specify several IPs of different time servers, this increases reliability, as does the use of a "pool address" that accesses several time servers.
Further information can be found at:
More accurate and reliable: an internal time server
