Specifications

Administrator's Manual 12. Configuring Date and Time
12.3 Configuring Network Time Protocol Server via DHCP
If the IP Phone is set to obtain GMT offsets and NTP servers via DHCP (default), it
receives the following fields in the DHCP options:
 Primary Server and Secondary Server – (Option 4 or 42).
Note: If both options (4 and 42) are received, the higher priority is given to
Option 42.
 Time Zone – (Option 2)
The IP Phone sends an NTP request to the Primary NTP server. If there is no response,
the NTP request is sent to the Secondary NTP server.
After obtaining the time from the server it adds the GMT offset in Option 2 and this is the
updated system time.
 To manually configure the NTP Server and GMT offset via DHCP:
 Using the Web:
1. Access the ‘Date and Time’ page (Configuration tab > Advanced Applications
menu > Date and Time).
2. From the “Obtain Time Zone From DHCP” drop-down list, select Disable.
3. Configure the NTP and Time Settings according to the parameters in the table
below, and then click Submit.
Note: These values will have no affect if the timezone is set to be obtained from
DHCP. If the Time Zone and NTP servers are manually set, the IP Phone
acts the same as described above, but the values are obtained from
configuration file and not from DHCP.
Figure 12-3: NTP and Time Settings Web Fields
Table 12-3: NTP Server and GMT Parameters
Parameter Description
[network/lan/dhcp/ntp/gmt_offset]
Enables the NTP server from which the phone
retrieves the date and time.
 [0] Disable (default)
 [1] Enable – obtains the time information
from a configured NTP server
Version 2.0.0 69 October 2012