Panasonic KX-TDA0490 Getting Started page 83

2.2 Programming
server to assign a static IP address to the card from a pool of IP addresses that is defined in advance.
For more information about DHCP server settings, consult your network administrator.
In addition, it is also necessary to specify the values for the parameters under IP Address Settings
as they will be assigned by the DHCP server.
Programming Guide 13