Chapter 23 Sntp Configuration; Sntp Introduction - Digitalchina Networks DCS-3950 series Manual

DCS-3950 series Ethernet switch manual

Chapter 23 SNTP Configuration

23.1 SNTP Introduction

The Network Time Protocol (NTP) is widely used for clock synchronization for global
computers connected to the Internet. NTP can assess packet sending/receiving delay in
the network, and estimate the computer's clock deviation independently, so as to achieve
high accuracy in network computer clocking. In most positions, NTP can provide accuracy
from 1 to 50ms according to the characteristics of the synchronization source and network
route.
Simple Network Time Protocol (SNTP) is the simplified version of NTP, removing the
complex algorithm of NTP. SNTP is used for hosts who do not require full NTP functions, it
is a subset of NTP. It is common practice to synchronize the clocks of several hosts in
local area network with other NTP hosts through the Internet, and use those hosts to
provide time synchronization service for other clients in LAN. The figure below (Fig 23-1)
depicts a NTP/SNTP application network topology, where SNTP mainly works between
second level servers and various terminals since such scenarios do not require very high
time accuracy, and the accuracy of SNTP (1 to 50 ms) is usually sufficient for those
services.
Fig 23-1 NTP/SNTP work environment
DCS-3950 series switch implements SNTPv4 and supports SNTP client unicast as
described in RFC2030; SNTP client multicast and unicast are not supported, nor is the
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