NTP is widely used to synchronise the time on computers on the internet. NTP provides the
ability to access time services, organise the time synchronisation subnet and adjust the
local clock in each participating subnet computer. Typically, NTP provides accuracies of
between 1 and 50 milliseconds depending on the time source and network paths.
Network Time Protocol can be utilised to synchronise the time on computers across a network.
A time server is utilised to obtain the correct time from a time source and adjust the local time in each
participating computer. The time source used by the NTP time server is extremely important as this forms
the basis of all time updates across the network. Recent studies show an alarming number of stratum 1 time sources on the internet are bad time keepers. A reported 391 of 957
supposedly stratum 1 NTP time sources had time offsets of over 10 seconds. Incredibly, one time source was offset by a staggering 6 years. Only 28% of the internet based
stratum 1 clocks actually appears to be useful, based on research by Nelson Minar, MIT Media Lab Cambridge, MA USA .