IP SIP Phone v2
User’s Guide
Mar. 2005
[78/100]
The Simple Network Time Protocol is used to synchronize time with
IP SIP Phone
. If you
set SNTP server to Anycast mode, the phone will send SNTP query to LAN broadcast address.
Otherwise, it sends a request to the specified SNTP / NTP server, extracting the reported time
from the reply, and overwrites the phone’s time. Typically, SNTP / NTP servers operating in
broadcast mode send update messages every 64 to 1024 seconds. The default time on system
starting up is 00:00, January 1, 1970, GMT.
Unicast
Multicast
Anycast
Sends
SNTP request to the
specified SNTP server if
available.
Nothing
When in multicast mode,
SNTP requests are not
sent.
SNTP packet to the local
network broadcast
address,
224.0.1.1.
After the first SNTP
response is received, the
phone switches to unicast
mode with the server
being set as the one who
first responded.
Receives
SNTP response from the
SNTP server and ignores
responses from other
SNTP data via the SNTP /
NTP multicast address
from the local network
Unicast SNTP data from
the SNTP server that first
responded to the network