When you get fiber, a modem is no longer required. So keep the new router, it's probably. The answer depends on several factors, including your home's existing wiring setup, the age of your infrastructure, and the specific requirements of fiber optic technology. What Makes Fiber Optic Internet the Gold Standard? What Does "Rewiring" Mean for Fiber Optic Installation? Do I Need to Rewire. The direct answer to whether you need to rewire your house for fiber optic internet is: usually not for the fiber line itself, but potentially for your internal network distribution. The fiber optic cable typically terminates at a device called an Optical Network Terminal (ONT) installed either. Rewiring your home is generally not necessary for fiber optic internet installation. Fiber optic installation is designed to integrate seamlessly with your existing home network, making it an accessible upgrade for most homeowners. Do I Need a Special Router for Fiber Optic Internet? Fiber internet transmits data using light signals through fiber-optic cables, which differs from traditional. Do I still have the option choose an ONT and use my own router? Or are the Xfinity opto-routers the only option? I'm getting prepared for an upgrade from DSL (25Mbps) to fiber! Hello user_v6n7e4 and thank you so much for using our Xfinity Support Forums.