Yes, a router can work with fiber optic internet. The router connects to a fiber optic modem or Optical. However, setting up a fiber optic connection to your router can seem daunting if you're unfamiliar with the process. Why Use Fiber Optic Internet? Before diving into the setup, let's quickly. Fiber optic networks are celebrated for their speed and reliability, but even the best systems can encounter problems. Many major ISPs, such as Verizon and Xfinity, offer fiber connections directly to your door, known as FttP or Fiber.