Basically, there are three methods commonly performed for optical fiber testing: visible light source, power meter and light source (one jumper method), and optical time domain reflectometer (OTDR). Fiber optic cable is tested to ensure continuity and attenuation. In this guide, we'll walk through how to test fiber optic cable and best practices to simplify your next fiber test. Why Does Fiber Optic Testing Matter? Fiber internet offers better speed and performance than copper options, but the cables are very sensitive to bending, contamination, and physical. A structured testing methodology allows engineers and procurement teams to confirm that delivered fiber cables comply with design specifications and international standards. That process, thankfully, is a simple one.