UDC 004.942:001.57
MODELING OF THE BEHAVIOR OF SECURITY ELEMENTS UNDER THIRD-PARTY INFLUENCE ON THE PASSIVE COMPONENTS OF QUANTUM KEY DISTRIBUTION SYSTEM
E. V. Borisova, postgraduate student, RSREU, Ryazan, Russia;
orcid.org/0000-0002-0198-377X, e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.
In cryptography, security can be ensured by exchanging a secret key between two users, who are called Alice (the source) and Bob (the receiver). In quantum cryptography, key exchange is carried out via a quantum channel. Its security is based on the fact that any measurement of a quantum system will inevitably change the state of this system. Consequently, a third party, Eva, can get information from the quantum channel by performing a measurement, but legitimate users will detect it and, therefore, will not use the key. In practice, a quantum system is a single photon propagating through an optical fiber, and the key can be encoded by its polarization or by its phase, as was first proposed by Bennett and Brassard [1]. In 1992, quantum cryptography was first experimentally demonstrated at a height of more than 30 cm in the air with polarized photons [2]. Since then, several groups have presented implementations of both polarization [3] and phase coding schemes in optical fibers [4-5]. However, modern implementations of KRK systems do not correspond to their model concepts, and an attacker has the opportunity to intercept the secret key and remain unnoticed [6-11]. Quantum communication protocols are considered secure provided that all devices included in the system are fully characterized and side channels are closed. However, as a result of exposure to laser radiation, it is possible to change the characteristics of components of quantum communication systems, which leads to vulnerabilities in quantum key distribution system. The aim of the work is the possibility of applying the conclusions from this article in the practical assessment of the security of quantum communication systems – the assessment quantum key distribution systems security. The work contains recommendations on strengthening the security of signal source block in quantum communication systems. As countermeasures to protect against the effects of laser radiation, it is proposed to use optical fuses with a given threshold power limit, detectors for monitoring the input power of optical radiation and narrow-band optical filters at the entrance to the quantum communication system [12]. This article collects data and provides characteristics when using these components as security elements.
Key words: quantum connection, quantum communication, quantum cryptography, vulnerabilities of quantum communication systems, laser damage attack, quantum key distribution systems.