Accton Technology ES4710BD - Manual (Page 327)

326
E ES4710BD 10 Slots L2/L3/L4 Chassis Switch
Chapter 15 SNTP Configuration
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 15-1) 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 15-1 Working Scenario
ES4710BD implements SNTPv4 and supports SNTP client unicast as described in RFC2030; SNTP
client multicast and anycast are not supported, nor is the SNTP server function.
GPS receiver
Level 1 server
Level 2 server
DNS server Campus users Campus users router