Operational Features
41-001343-02 REV05 – 07.2014
5-18
Example 2
The following is an example of a custom time zone configuration in the configuration files using absolute time:
time zone name: Custom
dst [start|end] relative date: 0 #absolute
#start of DST
dst start month: 3 #March
dst start week: 2 #second full week
dst start day: 1 #Sunday
#End of DST
dst end month: 11 #November
dst end week: 1 #first full week
dst end day: 1 #Sunday
DHCP Time Offset (Option 2) Support
DHCP Option 42 enables the phone to be configured with the Network Time Protocol (NTP) server addresses. However,
NTP provides the Coordinated Universal Time (UTC) time so the phone requires the offset from UTC in order to deliver the
correct local time.
A User or Administrator can set the offset of UTC using DHCP Option 2.
An Administrator can enable Option 2 in the configuration files by setting the parameter “
time zone name
”. If this param-
eter contains the
DP-Dhcp
value, the phone derives the time and date from UTC and the time offset offered by the DHCP
server.
Using the IP Phone UI, a User or Administrator can enable the phone to use DHCP Option 2 by setting the following values
from the Country Code list on the phone:
On the IP Phone UI for 8 and 11-line phones, a User or Administrator can select
Preferences->Time and Date->Time Zone-
>Others
and choose “
DP-Dhcp
” from the displayed time zone list.
On the IP Phone UI for 3-line phones, you select
Preferences->Time and Date->Time Zone->Others
and enter “
DP
” for the
country code, or press “
*
” and select “
Dhcp
” from the displayed time zone list.
On the 6739i, a User or Administrator can select
Set Time->Timezone->Others
and choose “
DP-Dhcp
” from the displayed
time zone list.
If you enable DHCP Option 2 via the IP Phone UI, the change takes place dynamically.
References
For more information about setting DP-DHCP for the timezone, see Appendix A,
For more information about setting the country code, see Appendix A,
“Country Codes (from Standard ISO 3166)”
Country Name
Country Code
Dhcp
DP
Note:
The country name, country code, and time zone name are case sensitive.
Notes:
•
When DHCP Option 2 is enabled on the phone, the phone still uses the values configured for
Daylight Savings
to
control daylight savings time.
•
The default behavior for the phone is to use the NTP server from Option 42 (or current configuration setting) and the
current time zone settings.
•
If the time zone name parameter is set to a value other than Dhcp, then DHCP Option 2 is disabled.