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An Optical-Fiber-Based Key for Remote Authentication of Users and Optical Fiber Lines.

Alexander Smirnov¹, Mikhail Yarovikov¹, Ekaterina Zhdanova¹

¹Terra Quantum AG, Kornhausstrasse 25, CH-9000 St. Gallen, Switzerland.

Sensors (Basel, Switzerland)

|July 29, 2023

Summary

Optical fiber

Keywords:

Rayleigh backscattering authentication identification optical communications optical fiber optical time domain reflectometry physically unclonable function

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Area of Science:

Optical physics
Telecommunications engineering
Information security

Background:

Standard telecommunication fibers possess unique internal structural inhomogeneities.
These inhomogeneities can be leveraged for security applications.
Existing authentication methods may have vulnerabilities.

Purpose of the Study:

To explore the use of optical fiber inhomogeneities for remote authentication.
To demonstrate the feasibility of observing unclonable backscattered signal patterns.
To investigate the physical basis and characteristics of these patterns.

Main Methods:

Utilizing optical time domain reflectometry (OTDR) to analyze backscattered signals.
Investigating the spatial periods and physical nature of detected patterns.
Experimentally verifying the properties of these patterns as physically unclonable functions (PUFs).

Main Results:

Observed unclonable backscattered signal patterns over tens of kilometers.
Identified refractive index fluctuations in standard telecommunication fibers as the source.
Confirmed the uniqueness and reproducibility of these fiber-based patterns.
Demonstrated their suitability as physically unclonable functions (PUFs).

Conclusions:

Optical fiber inhomogeneities offer a novel approach to remote authentication.
OTDR can effectively detect and analyze these unique fiber characteristics.
The proposed method provides a physically unclonable security solution for fiber optic lines.