How To Synchronise a Network

All computers maintain system time from an internal real-time clock chip. These devices are generally relatively low-cost and as a consequence tend not to keep good time. In fact, computers are notorious for providing inaccurate time and can drift by several minutes each day. This has serious consequences for networked computer systems and applications. Each computer can have wildly differing system times, which can be totally unacceptable for transaction processing applications. A solution is available in the form of network NTP servers. These allow all the servers, workstations and other infrastructure on a network to synchronise to a single accurate time reference. A Time Server obtains precise time from an external time reference and maintains an accurate internal time. This time is then made available to network clients for synchronisation.
The Network Time Protocol (NTP) is the standard means of network time synchronisation. The protocol defines a number of messages, or packets of information, that are passed between a time server and a client in order to achieve synchronisation. Most operating systems, including Microsoft Windows, LINUX, UNIX and Netware have integrated NTP or SNTP client software. Client software is also freely downloadable from Internet sites under the GNU public licence.