Quantum random number based secure encryption UFMC-PON transmission system

Universal filtered multi-carrier (UFMC) is promising for passive optical networks (PON) because it subdivides the available channel bandwidth into multiple sub-channels to mitigate the inter-symbol interference caused by fiber chromatic dispersion. However, PON is a point-to-multipoint transmission system with the intrinsic security vulnerability. To enhance the security of UFMC-PON, we proposed a quantum random number generator (QRNG) based secure encryption scheme, where the UFMC signal is masked by the generated random sequence with true randomness in five dimensions, i.e., constellation, symbols, subcarriers, sub-bands and phases, to resist brute force cracking. In these dimensions, the phase is encrypted by the QRN based on selective mapping algorithm, which contributes 2.0-dB PAPR suppression and enhances the security. The proposed scheme has been experimentally demonstrated in a 10-km 7-core fiber transmission, where the signals and the key are allocated into the various cores. For the brute force cracking, 8.1 x 1026 operations are required in the proposed secure architecture, which will take 128-year to recover the signal for a supercomputer with 20 x 1016 calculations per second.