If the status light ring is off (no color), it means your router is not connected to the network. The most common causes of this are loss of power to the fiber terminal (ONT) or an unplugged network cable. Make sure you have an Ethernet cable plugged fully into the WAN port on the. When issues like signal loss, slow speeds, or intermittent connectivity arise, systematic troubleshooting is key. This guide will walk you through diagnosing and resolving common fiber network issues efficiently. Why Do Fiber Networks Fail? Despite their robustness, fiber networks can fail due to:. One of the most common problems in fiber optic networks is the misalignment of the transmit (TX) and receive (RX) pairs. This comprehensive guide combines industry standards with field-tested practices to ensure you achieve a rock-solid. Setting up your FTTP connection box (ONT) is the first step to enjoying fast, reliable fiber internet. Here's what you need to know: What You'll Do: Mount and connect the FTTP box (ONT).