Atomic clocks are accurate timekeeping devices developed by man. Modern atomic clocks are so accurate that, also lost 100 million years, less than one second of time would go.
This accuracy makes it ideal reference for an NTP server (Network Time Protocol). NTP is a protocol, much to synchronize computer networks over the Internet from Local Area Network (LAN).
This article describes how to synchronize a computer network with NTP, a> Atomic clock source.
Atomic clocks are so accurate that a general time limit has been developed called UTC (Coordinated Universal Time), which is based on the time told by atomic clocks. UTC is used worldwide and is the same everywhere so that different computer networks to be synchronized at the same time.
Unfortunately, atomic clocks are extremely expensive, extremely delicate and quite bulky equipment so that they can only reallylarge-scale physics laboratories or in highly technical equipment such as satellites.
Synchronize Fortunately own NTP servers can to the UTC time with an atomic clock as the source of the two gives us the national time and frequency transmissions or the GPS (Global Positioning System) network.
Many national physics laboratories such as NPL in the United Kingdom, Germany NPL and NIST in the United States UTC time, a reference to long-wave radio broadcastTransmission. These signals can be picked up from an NTP server with a radio receiver. Unfortunately, the radio transmissions are not broadcast by all countries, and the signals is finite.
Fortunately, the constellation of satellites that make up the GPS network of the United States all have an atomic clock on board. This signal is used by satellite navigation receivers, used to work out position, but can also by a GPS NTP server as a timing source.
Either with a radio-referencedNTP server or GPS time server synchronization to be possible within a few milliseconds of UTC.
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