Attenuation refers to the amount of signal loss as it travels down the fiber, typically expressed in dB/km. Losses can be caused by scattering, absorption, dispersion & bending. Fiber optic cables are the backbone of modern communication systems, used to transmit telephone signals, internet data, and cable television signals. Losses can be divided into intrinsic and. Fiber optic cables transmit information across vast distances by sending pulses of light through thin strands of glass or plastic.