You cannot replace the function of a router with the AP150WN1X1OD. You need a router connected to a modem to access the Internet.
The AP150WN1X1OD can be used to create a wireless access point for a router, switch, or networking device that does not have wireless capabilities. When you use the AP150WN1X1OD to create a wireless access point, wireless devices can be connected to a wired device. To connect a wireless device to a wired device, connect the wired network connection to the LAN port on the POE injector (gray box) or on the LAN port of the unit.
For more information about how to set up an access point, refer to the following FAQ: http://www.startech.com/faq/networking_ap150wn1x1od_access_point_setup.