Achieving Perfect Secrecy by pdf-Bandlimited Jamming

摘要

Nowadays, the most investigated concepts of physical layer security encompass asymptotic criteria of secrecy. Taking a different perspective, in this work we come back to Shannon's original formulation of perfect secrecy, amounting to impose exactly zero mutual information between the source message and the data gathered by the eavesdropper. By jamming the intruder with a special class of noise-that we call pdf-bandlimited-and adopting a novel “out of the (pdf) band” information encoding technique, it is shown that a perfectly secure communication can be in fact sustained over the main channel, leaving no chances to the eavesdropper.