That's the port where a cable will attach to carry data from the fiber optic network to your device. The port on your modem or router should be located on the back or the side. Your internet service provider (ISP) usually supplies this. Ensure your fiber. This conversion happens either through an Optical Network Terminal (ONT) or directly via specialized router ports. This specialized equipment serves as the. Connecting a fiber optic cable to a router might seem daunting at first, but with the right tools and a bit of patience, it's a straightforward process. The technician powers, tests, and.