Why? Because the WAN port of the router is somewhere inside the device and no one I know has modified it to be external. So no.
I have a TP-Link W8901N (ADSL2+ Modem, Wireless N Access Point and 4-Port Router, in a single device) which I am currently using to connect to the internet via the RJ-11 input. I am planning to change my ISP, and the new ISP is providing internet access to my home via RJ-45 connector, which I can simply plug-in into my RJ-45 socket on my system and get connected. My question is since the manufacturer states "Modem, Wireless N Access Point and 4-Port Router, in a single device," can I use this as a standalone router to connect 2 or 3 systems via the RJ-45 socket on the TP-Link?