What is the use of NTP time calibration server?

Time calibration server, also known as NTP server, is a device developed for time calibration of computers, automation devices, etc. It can enable computers to synchronize their servers or clock sources, and it can provide high accuracy time correction, and can prevent vicious protocol attacks through encrypted confirmation.

#The operating environment of this article: Windows 7 system, Dell G3 computer.

NTP server can enable a computer to synchronize its server or clock source (such as quartz clock, GPS, etc.). It can provide high-precision time correction (the difference between the standard and the LAN is less than 1 millisecond, WAN tens of milliseconds), and can prevent vicious protocol attacks through encrypted confirmation. Time is propagated by NTP server level. Group all servers into different Stratum (tiers) based on their distance from external UTC sources.

NTP provides accurate time. First, there must be an accurate time source. This time should be UTC, the international standard time. The time source for NTP to obtain UTC can be atomic clocks, observatories, satellites, or it can be obtained from the Internet. This provides an accurate and reliable time source. Time is propagated by NTP server level. Group all servers into Stratum (tiers) based on their distance from the external UTC source. Stratum-1 is at the top level and has external UTC access, while Stratum-2 gets the time from Stratum-1, Stratum-3 gets the time from Stratum-2, and so on, but the total number of Stratum layers is limited to 15. All these servers are logically connected to each other in a ladder-like architecture, and Stratum-1's time server is the foundation of the entire system.

Computer hosts are generally connected to multiple time servers, using statistical algorithms to filter the time from different servers to select the best path and source to correct the host time. Even if the host cannot contact a certain time server for a long time, the NTP service still runs effectively.

In order to prevent malicious damage to the time server, NTP uses an identification (Authentication) mechanism to check whether the time information comes from the declared server and check the return path of the data to provide protection against interference. protection mechanism.

Extended information

NTP protocol

In the computer world, time is very important, such as for rocket launches This kind of scientific research activity has very high requirements for the unity and accuracy of time. Should it be based on the time of computer A or the time of computer B?

NTP is used to solve this problem. NTP (Network Time Protocol) is a protocol used to synchronize the time of various computers in the network. Its purpose is to synchronize the computer's clock to UTC. Its accuracy can reach 0.1ms within the local area network, and its accuracy can reach 1-50ms in most places on the Internet.

Group all servers into different Stratum (tiers) according to their distance from external UTC sources.

NTP provides accurate time. First, there must be an accurate time source. This time should be UTC, the international standard time. The time source for NTP to obtain UTC can be atomic clocks, observatories, satellites, or it can be obtained from the Internet. This provides an accurate and reliable time source.

Time is propagated according to the level of NTP server. Group all servers into Stratum (tiers) based on their distance from the external UTC source. Stratum-1 is at the top level and has external UTC access, while Stratum-2 gets the time from Stratum-1, Stratum-3 gets the time from Stratum-2, and so on, but the total number of Stratum layers is limited to 15. All these servers are logically connected to each other in a ladder-like architecture, and Stratum-1's time server is the foundation of the entire system.

Computer hosts are generally connected to multiple time servers, using statistical algorithms to filter the time from different servers to select the best path and source to correct the host time. Even if the host cannot contact a certain time server for a long time, the NTP service still runs effectively.

In order to prevent malicious damage to the time server, NTP uses an identification (Authentication) mechanism to check whether the time information comes from the declared server and check the return path of the data to provide protection against interference. protection mechanism.

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