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Quantum-noise--randomized data-encryption for WDM fiber-optic networks

Eric Corndorf·Chuang Liang·Gerg S. Kanter·Prem Kumar·Horace P. Yuen
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Abstract

We demonstrate high-rate randomized data-encryption through optical fibers using the inherent quantum-measurement noise of coherent states of light. Specifically, we demonstrate 650Mbps data encryption through a 10Gbps data-bearing, in-line amplified 200km-long line. In our protocol, legitimate users (who share a short secret-key) communicate using an M-ry signal set while an attacker (who does not share the secret key) is forced to contend with the fundamental and irreducible quantum-measurement noise of coherent states. Implementations of our protocol using both polarization-encoded signal sets as well as polarization-insensitive phase-keyed signal sets are experimentally and theoretically evaluated. Different from the performance criteria for the cryptographic objective of key generation (quantum key-generation), one possible set of performance criteria for the cryptographic objective of data encryption is established and carefully considered.

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Eric Corndorf, Chuang Liang, Gerg S. Kanter, Prem Kumar, Horace P. Yuen. 2005-03-29. Quantum-noise--randomized data-encryption for WDM fiber-optic networks. https://doi.org/10.1103/physreva.71.062326

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