19
Device management
Settings
Access the
Settings
page to change the device name, location, and system time.
System time sources
Correct system time is essential to network management and communication. Configure the system
time correctly before you run the device on the network.
The device can use the manually set system time, or obtain the UTC time from a time source on the
network and calculate the system time.
•
When using the locally set system time, the device uses the clock signals generated by its
built-in crystal oscillator to maintain the system time.
•
If you change the time zone or daylight saving settings without changing the date or time, the
device adjusts the system time based on the new settings.
•
After obtaining the UTC time from a time source, the device uses the UTC time and the time
zone and daylight saving settings to calculate the system time. Then, the device periodically
synchronizes the UTC time and recalculates the system time.
•
If you change the time zone or daylight saving settings, the device recalculates the system time.
The system time calculated by using the UTC time from a time source is more precise.
Make sure the time zone and daylight saving setting are the same as the parameters of the place
where the device resides.
If the system time does not change accordingly when the daylight saving period ends, refresh the
Web interface.
Clock synchronization protocols
The device supports the following clock synchronization protocols:
•
NTP
—
Network Time Protocol. NTP is typically used in large networks to dynamically
synchronize time among network devices. It provides higher clock accuracy than manual
system time configuration.
•
SNTP
—
Simple NTP, a simpler implementation of NTP. SNTP uses the same packet formats
and exchange procedures as NTP. However, SNTP simplifies the clock synchronization
procedure. Compared with NTP, SNTP uses less resources and implements clock
synchronization in shorter time, but it is not as accurate as NTP.
NTP/SNTP operating modes
NTP supports two operating modes: client/server mode and symmetric active/passive mode. The
device can act only as a client in client/server mode or the active peer in symmetric active/passive
mode.
SNTP supports only the client/server mode. The device can act only as a client.
