Attenuation means signal loss over distance. They reduce unwanted drops in. Fiber Optic Testing Testing is used to evaluate the performance of fiber optic components, cable plants and systems. As the components like fiber, connectors, splices, LED or laser sources, detectors and receivers are being developed, testing confirms their performance specifications and helps. Customers often request to make optical fiber optic patch cords with extremely small insertion loss. For example, two days ago, a customer ordered an APC jumper with an insertion loss of less than 0. Understanding it is crucial for anyone involved in data centers, telecommunications, or enterprise networking.