Computers are generally very poor timekeepers. They rely on low-cost timing components that are widely used in general-purpose clocks and watches and are just as prone to drift. The real-time clocks and cheap crystal oscillators integrated on to PC boards can cause system time to drift by several minutes each day. However, there are software solutions on hand to correct time drift and maintain accurate system time on your computer. This article describes techniques that can be used to eliminate system clock drift and keep precise time on your computer and across your network. It describes how Internet based time servers and the NTP time protocol can be used to keep accurate synchronized time on your computer.
There are a large number of Internet based time references that use the Network Time Protocol (NTP) to synchronize time clients. NTP was developed over twenty-five years ago at the University of Delaware by Dr D. Mills, it remains one of the oldest protocols in constant use. The protocol was developed to provide accurate synchronization of time between time servers and clients. Internet based NTP servers synchronize their time to accurate external reference clocks, such as GPS, national radio time standards or precise atomic clocks. Accurate time is then passed from the NTP server to network clients for synchronization.