The present disclosure relates to a non-invasive and real-time diagnostic analysis concept for an operational single mode optical fiber communication system and methods of using said system. The system comprises an optical fiber capable of being diagnosed non-invasively comprising an optical fiber for conveying a light beam that comprises an optical fiber comprising a first end for receiving the light beam and a second end opposed thereto, a core comprising an inner wall, and a cladding surrounding the core, the optical fiber further comprising at least one uncladded portion comprising a plurality of quantum dots dispersed in a medium, and wherein the quantum dots become activated by evanescent wave coupling resulting from total internal reflection of the light beam contacting the inner wall of the optical fiber core and wherein the activation results in emittance of light from the quantum dots.