Installing a Dedicated NTP GPS Time Server
NTP servers (Network Time Protocol) are devices that can synchronise a computer network to an authoritative UTC time source. UTC # (Coordinated Universal Time) is a global time scale used throughout the world and provided by atomic clocks.
NTP servers can receive UTC time either across the Internet from places such as nist.gov or windows.time. However, it must be noted that Internet based timing references can't be authenticated and may leave a network vulnerable to malicious attacks such as DDoS (Distributed Denial of Service - normally caused by malware that floods a server with traffic) that blocks access.
Fortunately dedicated NTP servers can receive an authenticated timing reference through either the GPS network (Global Positioning system) or specialist long wave radio broadcasts normally emitted from a national physics laboratory. Some NTP servers can receive both signals and even use them at the same time to ensure better accuracy.
GPS NTP servers are extremely easy to install as most time server manufacturers supply easy-to-use software with their devices.
Normally a GPS NTP server consists of a rack mount NTP time server, A GPS receiver and IEC Power Cables. For installation first locate a suitable area for the rack mount NTP Time Server in the rack mount enclosure, bearing in mind you will need to run a cable from this location preferably to the roof of the building or by a window if you are using GPS.
Locate an area to mount the GPS antenna, the ideal place would be the roof of the building with a 180 degree view of the sky but bear in mind that you will need to keep the GPS antenna close to the power source on the roof of the building. Things to avoid are air conditioning units and power distribution units as these will cause electrical interference.
The cable should be run from the rackmount enclosure to the selected mounting position leaving some slack cable in case you need to move the unit at a later date! Note: The maximum workable cable length for a GPS time server is 1000 meters (1km).
The four core cable is attached to the rear of the rackmount NTP Time Server using a small junction box. The standard wiring for the GPS antenna is as follows:
1 - Brown, 2 - Orange, 3 - Yellow, 4 - Green, 5 - Blue, 6 - White
With both units wired first power the GPS antenna then power up the rackmount server. Some time servers gave a small LCD screen at the front where on screen diagnostics are displayed. In most cases the unit will synchronise within 15 minutes, the delay is due to the GPS antenna locating and synchronising to satellites.
The configuration of the NTP Time Server can be achieved over the network using an internet browser.