A 20-meter fiber optic cable cannot directly connect to a router 300 meters away; you need a longer cable or intermediate devices to maintain signal integrity.

Distance Limitations

Fiber optic cables transmit data using light, which allows for long-distance communication with minimal loss. However, a 20-meter cable is far shorter than the 300 meters required, so the signal will not reach the router without additional infrastructure. For typical single-mode fiber, distances up to several kilometers are possible, while multi-mode fiber is limited to a few hundred meters depending on the data rate and cable type.

Practical Solutions

1. Use a longer fiber cable: Replace the 20m cable with a pre-terminated fiber optic cable of at least 300 meters, ensuring it matches the fiber type (single-mode or multi-mode) supported by your router or ONT .
2. Install a media converter or switch: If you must use the 20m cable, you can place a fiber media converter or switch closer to the router to extend the connection. The 20m cable would connect to the first device, and a longer fiber segment would bridge the remaining distance.
3. Check router and ONT compatibility: Ensure your router supports fiber input via an SFP port or WAN port and that the fiber type matches the ONT or ISP-provided equipment .

Additional Considerations

• Signal loss and attenuation: Over long distances, fiber experiences minimal loss, but connectors, splices, and bends can reduce performance. Use pre-terminated cables and avoid sharp bends to maintain signal quality .
• Connector type: Ensure the connectors (LC, SC, APC, or UPC) are compatible with both the ONT and router ports.
• Installation environment: For outdoor runs, use fiber with protective jackets suitable for burial or overhead installation.

Summary

A 20-meter fiber optic cable is insufficient for a 300-meter connection. To achieve reliable connectivity, either replace the cable with a 300-meter fiber or use intermediate devices like media converters or switches to bridge the distance. Always verify fiber type, connector compatibility, and signal integrity to ensure optimal performance .