An Optical-Fiber-Based Key for Remote Authentication of Users and Optical Fiber Lines

We have shown the opportunity to use unique inhomogeneities of internal structure an optical fiber waveguide for remote authentication users or optic line. Optical time domain reflectometry (OTDR) is demonstrated be applicable observing unclonable backscattered signal patterns at distances tens kilometers. The physical nature detected was explained, and their characteristic spatial periods were investigated. are due refractive index fluctuations a standard telecommunication fiber. experimentally verified that example physically function (PUF). uniqueness reproducibility been outline protocol has proposed.