The typical solution is install the fiber modem in the best place for the fiber, and then run a single ethernet line to your router. If it's an all-in-one box you can probably get it changed. In this guide, we'll walk you through how to connect a fiber optic cable to a router safely and efficiently. Just connect an Ethernet cable from. Is AT&T fiber run directly to inside home and customer's router or to a junction box outside the house where the connection is made? I am considering getting AT&T fiber Internet service as my ISP. The fiber line terminates at the Optical Network Terminal (ONT), which is typically supplied and installed by the internet service provider. This specialized equipment serves as the.