Secret key exchange in ultra-long lasers by radio-frequency spectrum coding


We propose a new approach to the generation of an alphabet for secret key exchange relying on small variations in the cavity length of an ultra-long fiber laser. This new concept is supported by experimental results showing how the radio-frequency spectrum of the laser can be exploited as a carrier to exchange information. The test bench for our proof of principle is a 50 km-long fiber laser linking two users, Alice and Bob, where each user can randomly add an extra 1 km-long segment of fiber. The choice of laser length is driven by two independent random binary values, which makes such length become itself a random variable. The security of key exchange is ensured whenever the two independent random choices lead to the same laser length and, hence, to the same free spectral range.

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Divisions: College of Engineering & Physical Sciences > Aston Institute of Photonics Technology (AIPT)
College of Engineering & Physical Sciences > Systems analytics research institute (SARI)
Additional Information: This work is licensed under a Creative Commons Attribution 3.0 Unported License. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit Funding: French National Research Agency (grants LABEX SIGMALIM and ANR 08-JCJC-0122 PARADHOQS); European Research Council (project ULTRALASER); Leverhulme Trust (grant RPG-278); Spanish MICINN project TEC2011-27314 (RAMAS); and XLIM Institute (grant VIP2013).
Uncontrolled Keywords: fiber lasers,fiber optics communications,optical security,encryption
Publication ISSN: 2047-7538
Last Modified: 22 Apr 2024 07:11
Date Deposited: 02 Apr 2015 13:30
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Related URLs: http://www.natu ... lsa201549a.html (Publisher URL)
PURE Output Type: Article
Published Date: 2015-04-24
Published Online Date: 2015-01-27
Authors: Tonello, Alessandro
Barthélémy, Alain
Krupa, Katarzyna
Kermène, Vincent
Desfarges-Berthelemot, Agnès
Shalaby, Badr Mohamed
Boscolo, Sonia (ORCID Profile 0000-0001-5388-2893)
Turitsyn, Sergei K. (ORCID Profile 0000-0003-0101-3834)
Ania-Castañón, Juan Diego



Version: Published Version

License: Creative Commons Attribution

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