Posted by Richard N Williams on April 24th, 2012
Most of us know how useful the GPS network is. The Global Positioning System has changed the way we navigate on the road, and most modern cars are sold complete with some form of satellite navigation system already installed. However, the Global Positioning System is not only useful for satellite navigation; it has other uses too, especially as a source of accurate time for synchronising a computer network and other such technologies with the aid of a GPS network time server.
Need for Synchronisation
Time synchronisation is vital for all sorts of technologies, especially computer networks. Having different machines with a different time can lead to all sorts of untold problems, from data getting lost to simple things such as emails arriving before they were technically sent. Without accurate synchronisation or a network time server, it is nearly impossible to keep a network running smoothly and pinpoint errors and bugs.
Other technologies too need complete synchronicity. CCTV cameras, cash machines and safety systems such as air traffic control all have to be precisely synchronised. Imagine the chaos if your local cash machine told a different time from the one next to it. In effect, you could withdraw money from one machine, while the one next to it would consider a transaction that hadn’t happened yet, allowing you to withdraw the same amount again.
The Global Positioning System doesn’t actually transmit any positioning information. The reason that satellite navigational systems can work out accurate positioning is due to the time signals that the GPS satellites transmit. Onboard each GPS satellite is a couple of atomic clocks. These clocks transmit their times and exact position of the satellite and it’s this information, triangulated from three or more satellites that a navigational system uses to work out exactly where it is in the world.
Atomic clocks have to be used for this process because the signals are travelling at the speed of light. A one-second inaccuracy in the time signal would lead a satellite navigational system to be in error of over 300,000 km. And it’s a testament to the atomic clocks on GPS satellites that most sat nav systems are accurate to within a few metres.
GPS Network Time Server
Because of the accuracy of the GPS time signals, and the fact that the signal are available anywhere on the planet, the GPS network is ideal for use as a master time source for computer network time synchronisation. To synchronise a computer network or other technology systems to GPS time, all that is required is a GPS network time server.
GPS network time servers do all the work for you. By use of a rooftop antenna, the time server receives the GPS signal and distributes it around a network of machines. By use of time synchronisation protocols such as NTP (Network Time Protocol), all devices can be kept within a few milliseconds of the original GPS time source. And you don’t need multiple time servers for large networks either. A single device can synchronise hundreds of devices to GPS time.
GPS network time servers are simple to install, simple to use and can maintain millisecond accuracy for all sorts of technologies. Used by organisations as diverse as stock exchanges, air traffic control and banking systems, GPS time servers provide an efficient and cost effective solution to maintain network synchronicity.