Effective fiber testing utilizes advanced tools such as Optical Loss Test Sets (OLTS), Optical Time-Domain Reflectometers (OTDR), and Visual Fault Locators (VFL) to diagnose and correct issues, ensuring optimal network performance. Fiber Optic Testing Testing is used to evaluate the performance of fiber optic components, cable plants and systems. Related: Fiber Optic Connectors – Identification Guide Regularly testing fiber optic cables helps minimize network downtime, lengthens the network's longevity, reduces maintenance. After fiber optic cables are installed, spliced and terminated, they must be tested.