Presented herein are techniques to manage optical network infrastructure. A method includes inducing a predetermined vibration on a fiber optic cable, the predetermined vibration being sufficient to cause a change to at least one of a state of polarization and a phase of optical signals being carried by respective optical fibers in the fiber optic cable, detecting, at a first endpoint, using a first coherent optical receiver, and at a second endpoint, using a second coherent optical receiver, the change to the at least one of the state of polarization and the phase of the optical signals, and based on the detecting, determining that the first endpoint and the second endpoint are connected to, or in communication with, one another via at least one finer in the fiber optic cable.