A device may provide a signal with a first wavelength and a second wavelength to a fiber cable, and may receive an intensity change measurement of backscattered light based on the first wavelength of the signal. The device may receive a differential phase change measurement of the backscattered light based on the second wavelength of the signal, and may determine whether there is a fiber loss change, a fiber length change, and/or a fiber cut associated with the fiber cable based on the intensity change measurement. The device may determine whether there is an abnormal event associated with the fiber cable based on the differential phase change measurement, and may report one or more of the fiber loss change, the fiber length change, the fiber cut, or the abnormal event.