Network Time Protocol (NTP) servers are computer systems that are responsible for synchronizing the clocks of other computers or devices on a network. They do this by exchanging time information with each other using the NTP protocol, which is a networking protocol for synchronizing the clocks of computer systems over a network.
NTP servers are used to ensure that all devices on a network have the same, accurate time. This is important for many applications, such as logging and auditing systems, which rely on accurate timestamps to function properly.
NTP servers typically operate in a hierarchical structure, with a small number of high-precision “stratum 1” servers at the top of the hierarchy, and a larger number of lower-precision “stratum 2” servers below them. Stratum 1 servers are typically connected to a reliable time source, such as an atomic clock, GPS receiver, or radio clock, and are responsible for synchronizing their clocks with the time source. Stratum 2 servers are responsible for synchronizing their clocks with stratum 1 servers, and so on down the hierarchy.
In addition to synchronizing the clocks of devices on a network, NTP servers can also be used to synchronize the clocks of devices across networks, such as the Internet. To do this, NTP servers use a process called “time leap smoothing” to adjust for the varying delay times that can occur when transmitting time information over a network.
Overall, NTP servers are an important part of modern networking, ensuring that all devices on a network have the same, accurate time, which is essential for many applications.