Network Architecture

We are currently running Sonoma D12 NTP servers, each connected to a differential GPS antenna on the roof and each with a rubidium oscillator to provide a stable clock in the event of an issue with the GPS signal.

Each is capable of handling 7500 qps, and an explanation of how many clients they can support is given in NTP Server Load.


The four servers operate independantly and are not actively synchronised to each other. They use their internal GPS and rubidium oscillator as their only time source.

Host names

The four servers are called ntp[1-4] The host names that we ask you to access them by p[1-4] and s[1-4] are CNAMEs that we use to enable us to introduce more servers with different characteristics at a later stage without mucking people around. Rules on which names to use are given the in the Acceptable use policy.


  • ntp1 is in Albany connected via Vocus.
  • ntp2 is in Auckland CBD connected via ICONZ.
  • ntp3 is in Wellington CBD connected via Vocus.
  • ntp4 is in Christchurch connected via 2Degrees.

Software and Standards

The software is the standard NTPv4 distribution which supports the latest version of the NTP protocol (v3) and the Simple Network Time Protocol (SNTPv4).