Snom 220 - Manual (Page 52)

Settings
52
IP Gateway
This setting shows the IP address of the default IP gateway (not the
VoIP gateway). It is the address to which the packets are routed if the
wanted packet address is not in the current subnet. Setting up this
parameter is mandatory in order to reach an external network.
DNS
Domain
Specify the DNS domain for your phone here.
DNS Server 1
Specify the IP address of the DNS server for your network here.
DNS Server 2
Specify the IP address of a backup DNS server for your network here.
TIME SETTINGS
NTP Time server
Specify the URL or IP address of the NTP server here.
Timezone
Select the time zone most appropriate to your geographical location
through this option.
HTTP