This is a brief article of what it means with the different modes when setting up a new NBG-418v2.
Router mode - Use this mode if you wanty to use routing functions such as LAN DHCP, NAT, firewall and so on.
In other words, use router mode if you don't have a router at home, and need a router and WiFi.
WLAN = WiFi
LAN = cable
N = NBG-router
WAN = cable to internet (fiber, VDSL, ADSL etc.)
IAD = Internet Access Device (Modem f.ex.)
Access Point mode (AP mode) - Use this mode if you already have a Router in your network and you want to set up a wireless network and bridge the wired and wireless connections to the NBG-418v2.
In other words, use AP mode if you have a router at home without WiFi:
Repeater mode (Universal Repeater) - Use this mode to have the NBG-418v2 to be an access point and a wireless client at the same time.
In other words, use Repeater mode if you have a router with WiFi and wants WiFi in other parts of the area: