Abstract: An architecture, system and associated method and apparatus for securely communicating authentication data to a communication device. In one embodiment, the method includes modulating a spectral source's radiation using the authentication data, wherein the spectral source's radiation is adapted to operate as a first transmission medium for carrying the authentication data, the first transmission medium being containable within an enclosure that inhibits passage of the spectral source's radiation (i.e., spectrally opaque enclosure). The modulated authentication data is transmitted via the first transmission medium to the communication device disposed in the spectrally opaque enclosure.