D-Link DSL-2790U User Manual page 36

Configuration
WAN Service Configuration – BRIDGING
This summary window allows you to confirm the bridging settings you have just
made. Click the Apply /Save button to save your new bridging settings and
restart the Router.
To access the Wide Area Network (WAN) Service Setup window, click the WAN Service button in the Advanced Setup directory.
This window is used to configure the WAN interface. You can add and delete
WAN interface on this window.
If you are setting up the WAN interface for the first time, click the Add button.