No internet access after setting up the router for fiber optic connection

If you can't access the internet with a fiber optic router, the issue may be due to hardware, cabling, or configuration problems, and systematic troubleshooting can help identify the cause.Check Your Hardware and ConnectionsStart by inspecting all devices in your fiber setup: the Optical Network Terminal (ONT), your router, and any modems or wall power units. Ensure that the ONT is powered on and connected to a working electrical outlet, preferably a GFCI outlet if installed in a garage or outside your home. Verify that the Ethernet cable from the ONT to your router is securely plugged into the correct LAN/WAN port, and check for any visible damage to cables or connectors, including frays, bends, or contamination on fiber connectors .Check Indicator LightsMost fiber devices have LEDs indicating status. On the ONT, the Power LED should be on, the PON light should be active, and the Alarm LED should not be red. On your router, ensure the Data LED is on to confirm a connection to your home network. A blinking red light or an off LED may indicate a failure to obtain an IP address or a hardware issue .Restart DevicesPower cycle your equipment: unplug the ONT, router, and any modems for 30–60 seconds, then reconnect them. Wait for the indicator lights to stabilize. This can resolve temporary glitches and allow the router to obtain an IP address from the ONT .Test ConnectivityIf possible, connect a device directly to the router via Ethernet to rule out Wi-Fi issues. Run a speed test to see if the connection matches your plan. If speeds are significantly lower or there is no connection, the problem may be with the ONT, router configuration, or the fiber line itself .Firmware and ConfigurationEnsure your router's firmware is up to date. Incorrect IP settings, DHCP conflicts, or outdated firmware can prevent internet access. Logging into the router's admin panel can help verify settings and apply updates .Inspect Fiber CablesFiber optic cables are delicate. Check for bends, cuts, or contamination on connectors. Clean connectors with lint-free wipes and isopropyl alcohol if necessary. Signal loss due to physical damage or improper handling is a common cause of fiber outages .Contact Your ISPIf all hardware, cables, and settings appear correct but the internet still does not work, contact your ISP. They can check for network outages, verify the ONT's signal, and provide advanced diagnostics or technician support . By following these steps—checking hardware, inspecting cables, verifying LEDs, restarting devices, and updating firmware—you can often restore connectivity or identify whether the issue requires ISP intervention.