Linksys LGS326P

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Clock Source
System time can be set manually by the user, or dynamically from an SNTP server. If an SNTP
server is chosen, the manual time settings are overwritten when communications with the server
are established.
As part of the boot process, the device always configures the time, time zone, and DST. These
parameters are obtained from SNTP, values set manually, or if all else fails, from the factory
defaults.
•
Manual—User must manually set the time.
•
SNTP—Time can be received from SNTP time servers. SNTP ensures accurate network
time synchronization of the device up to the millisecond by using an SNTP server for the
clock source. When specifying an SNTP server, if choosing to identify it by hostname,
three suggestions are given in the GUI:
o
time-a.timefreq.bldrdoc.gov
o
time-b.timefreq.bldrdoc.gov
o
time-c.timefreq.bldrdoc.gov
Note—SNTP is the recommended method for time setting.
SNTP Modes
The device can receive system time from an SNTP server in one of the following ways:
•
Client Broadcast Reception (passive mode)—SNTP servers broadcast the time,
and the device listens to these broadcasts. When the device is in this mode, there
is no need to define a Unicast SNTP server.
•
Client Broadcast Transmission (active mode)—The device, as an SNTP client,
periodically requests SNTP time updates. This mode works in either of the
following ways:
o
SNTP Anycast Client Mode—The device broadcasts time request packets
to all SNTP servers in the subnet, and waits for a response.
o
Unicast SNTP Server Mode—The device sends Unicast queries to a list of
manually-configured SNTP servers, and waits for a response.
The device supports having all of the above modes active at the same time and selects the
best system time received from an SNTP server, according to an algorithm based on the
closest stratum (distance from the reference clock).
Time Zone and Daylight Savings Time (DST)
The Time Zone and DST can be set on the device in the following ways:
•
Dynamic configuration of the device through a DHCP server, where:
•
Dynamic DST, when enabled and available, always takes precedence over the manual
configuration of DST.