Knowing the exact time is a must. Either there is an appointment to attend or certain deadlines are concerned - it is the watch we are looking at. When somebody spends most of his time working at the computer, where does he often look? Right, in the bottom right corner of the monitor whre there is an electronic clock. A quartz crystal is fixed in the motherboard of a computer. The crystal, under the action of electric current, vibrates with exact and invariable frequency - this is the main element of computer clocks.
But even computer clocks are subject to precision faults and after a year's time use they already have minor errors. What is to be done? Periodically adjust the clocks? This seems quite uncomfortable. It is much better to fix the correct time once and not worry about this any more. But is this possible?Yes, it is.
Network Time Protocol (NTP) is a protocol designed to synchronize the clocks of computers to a common timebase. Its precision is due to the following elements:
- Client - the computer, when clock needs to be adjusted.
- NTP time server - a server continuously synchronized with the satellite or other NTP servers.
- Accurate clocks - as a rule, these are GPS satellites or satellites with caesium clocks incorporated, which periodically issue signals for time synchronization.
All the elements related to time accuracy exchange data by means of NTP. Obviously, the bigger the number of servers between client and satellite, less accurate is the data transmited. The distance between the satellite with the reference clock and the client is measured in stratum levels:
Stratum 0 These are caesium or GPS clocks. Stratum 1 Servers attached directly to Stratum 0 devices and receive signals from the satellite. Stratum 2 Servers connected via computer networks to Stratum 1 servers. Normally a Stratum 2 computer will reference a number of Stratum 1 servers and use the NTP algorithm to gather the best data sample.
Accurate time is necessary not just for office use. It is an absolute must for scientists, researchers in areas like physics, astronomy, audio and TV engineering etc. Accurate time is essential for defense system, state structures and represents one of the strategic resources of any state.
At present there are more than 1860 NTP servers in use around the world. Only 190 servers are Stratum 1 level. It means that anybody willing to adjust the computer clock can connect to one of these servers. In 2009 in Republic of Moldova, Startum 1 server has become availabe through Information Society Development Institute. Accurate time service can be accessed by people free of charge, simply by connecting to one of the following servers:
Domain: NTP.IDSI.MD (Stratum 1) IP: 193.226.65.36
Domain: NTP2.IDSI.MD (Stratum 2) IP: 193.226.65.2
To gain unlimited and warranted access to this service, please indicate for NTP client the symbolic name, i.e. NTP2.IDSI.MD, or the general symbolic name for all NTP servers in the Republic of Moldova: MD.POOL.NTP.ORG. |