Differences between NTP and SNTP
All Spectracom time servers are compatible with NTP (Network Time Protocol) and SNTP (Simple Network Time Protocol). The packets of information sent to and received from the time server does not differ between these two modes of operation. The packet structure doesn't vary. The time client software running on the PC determines whether NTP or SNTP is being used. The time server doesn't know or care which mode is running on the PC. The simplified difference between these two operating modes is in the algorithms used for time synchronization and the error checking that occurs. NTP calculates the drift of the PC clock and then adjusts the drift rate so that the time is always correct. SNTP jumps the time to the correct value at each specified interval. The NTP algorithm provides greater accuracy but is much more complicated to use.
Whether NTP or SNTP is used is determined by the time sync software running on the PC. The W32Time client software determines whether NTP or SNTP is used. Windows 2003 uses the NTP algorithms whereas Windows 2000, XP and NT all use the SNTP algorithms.