The firmware version is AU_2.01
Go to Setup > Internet Setup > ATM, then click 'Add' button.
Just use the default setting, then click 'Apply/Save' button.
Go to Setup > Internet Setup > WAN Service, then click 'Add' button.
Click 'Next' button.
Select 'Bridging' type, then click 'Next'.
Click 'Apply'.
DONE.