There are generally three methods for testing the insertion loss of optical fiber connectors: benchmark method, substitution method, and standard jumper comparison method. The estimate, called a "loss budget" is calculated using typical component losses for. Fiber loss can be also called fiber optic attenuation or attenuation loss, which measures the amount of light loss between input and output. Loss is expressed in decibels (dB) and accumulates across all elements of the optical path. In practical networks, total link loss is composed of. When testing fiber optic cabling, determining acceptable loss is crucial. Losses can be introduced by various means such as intrinsic material absorption, scattering, bending, connector loss and more.