Journal of Lightwave Technology

Photonic Layer Security in High-Speed Optical Communications

Dan Sadot, Ido Attia, Ohad Balasiano, Isaac Jonas, Yarden Yalinevich, Gil Alín, Elimelech Keller, Hamutal Shalom, Eyal Wohlgemuth

Published Dec 23, 2024• 12 citations

Publisher

Abstract

The capability to form a photonic shield by using a unique all-optical transmission scheme incorporating multi-THz coherent spreading, spectral phase encoding (SPE), and negative optical signal-to-noise ratio (OSNR) completely prevents offline deciphering of captured data-in-transit. This photonic shield scheme provides an ultimate solution to the “harvest-now, decrypt later” threat by eliminating unauthorised recording. Thus, no raw data is available for any post-processing, including by quantum computers. Both the full line rate payload and the asymmetric key exchange, are transmitted through the secured channel. This work presents an industry-level demonstration, including real-time client data transmission and seamlessly continuously changing spectral phase encoding (SPE) photonic keys. A 100 Gbps DP-QPSK signal and a 200 Gbps DP-16QAM link are established over 80 km of standard single mode fiber (SSMF).

DOI: 10.1109/jlt.2024.3520900

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