Abstract We have shown the opportunity to use the unique inhomogeneities of the internal structure of an optical fiber waveguide for remote authentication of users or an optic fiber line. Optical Time Domain Reflectometry (OTDR) is demonstrated to be applicable to observing unclonable backscattered signal patterns at distances of tens of kilometers. The physical nature of the detected patterns was explained, and their characteristic spatial periods were investigated. The patterns are caused by the refractive index fluctuations of a standard telecommunication fiber. We have experimentally verified that the patterns are an example of a Physically Unclonable Function (PUF). The uniqueness and reproducibility of the patterns have been demonstrated and an authentication protocol has been provided.
Abstract We have shown the opportunity to use the unique inhomogeneities of the internal structure of an optical fiber waveguide for remote authentication of users or an optic fiber line. Optical Time Domain Reflectometry (OTDR) is demonstrated to be applicable to observing unclonable backscattered signal patterns at distances of tens of kilometers. The physical nature of the detected patterns was explained, and their characteristic spatial periods were investigated. The patterns are caused by the refractive index fluctuations of a standard telecommunication fiber. We have experimentally verified that the patterns are an example of a Physically Unclonable Function (PUF). The uniqueness and reproducibility of the patterns have been demonstrated and an authentication protocol has been provided.
We have shown the opportunity to use the unique inhomogeneities of the internal structure of an optical fiber waveguide for remote authentication of users or an optic fiber line. Optical time domain reflectometry (OTDR) is demonstrated to be applicable to observing unclonable backscattered signal patterns at distances of tens of kilometers. The physical nature of the detected patterns was explained, and their characteristic spatial periods were investigated. The patterns are due to the refractive index fluctuations of a standard telecommunication fiber. We have experimentally verified that the patterns are an example of a physically unclonable function (PUF). The uniqueness and reproducibility of the patterns have been demonstrated and an outline of authentication protocol has been proposed.
Because of advancements in digital communication and associated technology, security and privacy have become crucial. Physical Unclonable Function (PUF) is one of the promising security solutions due to their adaptability, reliability, and secure nature. PUFs are unique identifiers that can be presented in many forms due to their unique structure and application. However, their application might be limited due to the reliability and fabrication process. Hence, a new PUF is proposed in this study, which comprises a semi-distributed fiber optic device. The proposed solution can overcome reliability concerns based on the unique behavior of biosensors and offers a simple fabrication process. Based on the random information of the physical characteristics, Physical Unclonable Functions has demonstrated potential for secure device authentication. This thesis describes the design, implementation, and evaluation of semi-distributed fiber optic devices as robust PUFs. Using intrinsic variability of fiber optic interferometric configurations, each device produces a unique spectrum showing good intra-device repeatability and high inter-device differentiation. Experimental validation of spectral reflectivity measurements confirms low internal variability, crucial for reliable authentication. In addition to these correlations, this research shows extensive simulations, allowing us to thoroughly analyze device uniqueness and stability, across a broad range of environmental scenarios. The proposed semi-distributed type of the fiber optic PUFs is promising solutions for secure and scalable authentication in applications that require high levels of security and integrity. This study represents a step towards the practical deployment and enhancement of fiber-optic PUF solutions into secure systems verification.
In this work, the concept of optical identification (OI) based on physical unclonable functions is introduced for the first time, to our knowledge, in optical communication systems and networks. The OI assigns an optical fingerprint and the corresponding digital representation to each sub-system of the network and estimates its reliability in different measures. We highlight the large potential applications of OI as a physical layer approach for security, identification, authentication, and monitoring purposes. To identify most of the sub-systems of a network, we propose to use the Rayleigh backscattering pattern, which is an optical physical unclonable function and allows OI to be achieved with a simple procedure and without additional devices. The applications of OI to fiber and path identification in a network and to the authentication of users in a quantum key distribution system are described.
We introduce a technique to generate and read the digital signature of the networks, channels, and optical devices that possess the fiber-optic pigtails to enhance physical layer security (PLS). Attributing a signature to the networks or devices eases the identification and authentication of networks and systems thus reducing their vulnerability to physical and digital attacks. The signatures are generated using an optical physical unclonable function (OPUF). Considering that OPUFs are established as the most potent anti-counterfeiting tool, the created signatures are robust against malicious attacks such as tampering and cyber attacks. We investigate Rayleigh backscattering signal (RBS) as a strong OPUF to generate reliable signatures. Contrary to other OPUFs that must be fabricated, the RBS-based OPUF is an inherent feature of fibers and can be easily obtained using optical frequency domain reflectometry (OFDR). We evaluate the security of the generated signatures in terms of their robustness against prediction and cloning. We demonstrate the robustness of signatures against digital and physical attacks confirming the unpredictability and unclonability features of the generated signatures. We explore signature cyber security by considering the random structure of the produced signatures. To demonstrate signature reproducibility through repeated measurements, we simulate the signature of a system by adding a random Gaussian white noise to the signal. This model is proposed to address services including security, authentication, identification, and monitoring.
Classical and quantum fiber-optic communication channels are vulnerable to possible intrusions. Quantum key distribution (QKD) provides a physically fundamental and theoretically secure communication method, but the key rate decays over long distances. Recently proposed by our group, a quantum communication protocol based on the physical estimation of an eavesdropper's influence shows extreme efficiency even at distances of thousands of kilometers. In this paper, we investigate the physical limits of eavesdropper detection using optical time domain reflectometry (OTDR) and demonstrate the successful detection of a 0.01 dB leakage over a distance of 1009 km.
We introduce time-domain physical unclonable functions (tPUFs) using photonic ring resonator networks, fabricated on a silicon nitride platform. These tPUFs demonstrate complex spectro-temporal behavior, enabling their use in secure, remote authentication schemes. Physical unclonable functions (PUFs) offer an alternative to conventional hash functions by leveraging the intrinsic randomness of physical structures [1], [2]. Optical PUFs have historically been realized using strongly scattering media [3], [4]. We introduce time-domain PUFs (tPUFs) that employ temporal scrambling, allowing for read-out over a single spatial mode. This allows integration into existing infrastructure, such as telecom fibers and satellite links.