Once both ends are terminated the fiber can be tested. Fiber testing used to involve a bulky OTDR (Optical Time Domain Reflectometer) operated by a geek with a degree in optical physics, but these days a simple hand held light source and power meter can be used. These test procedures assess the physical and functional qualities of fiber optic cables, connectors, and the network as a whole. As the components like fiber, connectors, splices, LED or laser sources, detectors and receivers are being developed, testing confirms their performance specifications and helps. Continuity testing verifies that the fiber is intact and that light can pass through from one end to the other without any blockages. Always inspect before you connect.
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