RU2672049C1 - Method for voice information leakage minimization through fiber optic lines - Google Patents

Abstract

FIELD: physics.SUBSTANCE: invention relates to the provision of information security of negotiations in dedicated premises by neutralizing channels for the leakage of voice information through fiber optic lines and can be used in systems of protection of confidential speech information. In a method for protecting against leakage of voice information through fiber optic lines, in that a portion is created on the fiber optic line, where an effect is exerted on the optical fiber resulting in modulation of the light streams passing through it in both directions at frequencies of acoustic noise of various spectra or specially processed speech, in this case, acousto-vibration effect on the optical fiber is carried out along the whole length of the protected room.EFFECT: technical result consists in expanded field of application.1 cl, 1 dwg

Description

The invention relates to the field of ensuring information security of negotiations in allocated premises by neutralizing the channels for the leakage of voice information through fiber-optic lines and can be used in systems for protecting confidential voice information.

Known methods of neutralizing the effects of acoustic fields on the optical fiber of the cable by means of a special soundproofing sheath of the fiber and cable, which reduces the effect of vibration and sound on the light parameters in fiber-optic communication lines. For example, in accordance with the "Rules for the use of optical communication cables, passive optical devices and devices for welding optical fibers", approved by order of the Ministry of Information Technologies and Communications of the Russian Federation of 04.19.2006 No. 47 (registered by the Ministry of Justice of Russia on 28.04.2006, registration number 7772), cable manufacturers are required to resist the optical cable to vibration loads with acceleration up to 40 m / s ² in the frequency range from 10 to 200 Hz. However, this does not provide complete protection against the acoustic-fiber-optic channel for the leakage of speech information, which is associated with the possibility of creating acoustic contact with the cable both unintentionally during installation and operation, and especially by an attacker.

Known methods of neutralizing the local influence of acoustic fields on a fiber optic cable by including in the fiber optic communication line special equipment that restores the parameters of light pulses in it — repeaters, signal regenerators. For example, an optoelectronic decoupling device for 1 SC ОРУ-1 port or 2 SC ОРУ-2 ports manufactured by FSUE KBPM (Moscow). The principle of operation of the device is associated with the conversion of an optical signal into an electrical one and subsequent conversion into an optical signal, cleared of noise, including acoustic nature. In addition to special equipment, any active fiber-optic equipment in the network inevitably destroys the acousto-optic fiber channel of the leak, since the original digital modulation is restored in it and the noise effects disappear. But the use of special and / or active equipment itself carries the risk of leakage, which requires special maintenance, placement next to the protected room in a special cabinet, regulated functional checks, etc. And also, such equipment requires special protection against leakage due to spurious electromagnetic radiation and interference, which is associated with electronic components of the equipment with electrical power circuits from the network.

Closest to the claimed is a known method of protection [1], which consists in the fact that a localized area is created in the fiber-optic channel where local exposure to the optical fiber is performed, leading to the modulation of light flows passing through it in both directions at frequencies of acoustic noise of various spectra or specially processed speech. The method of forming an effect on a fiber optic cable can be different both in terms of the physical field and in the form of implementation. The main disadvantage of this method is the local exposure to acoustic noise, since methods for analyzing the spectra of signals arriving through an acousto-optic fiber channel from separate sections of a fiber optic cable line are known [2-5]. Accordingly, the input of the noise signal into the acousto-optic fiber channel at the local section of the fiber-optic cable line does not completely neutralize the leak of confidential speech information from the neighboring section.

The essence of the alleged invention is the expansion of the scope.

This essence is achieved by the fact that, according to the method of protection against leakage of speech information through fiber-optic lines, which consists in the fact that on the fiber-optic line create a section where they act on the optical fiber, leading to the modulation of light streams passing through it in both directions at the frequencies of acoustic noise of a different spectrum or specially processed speech, while performing an acoustic-vibrational effect on the optical fiber along the entire length of the protected room.

The drawing shows a structural diagram of a device for implementing the proposed method.

The device contains a source of acoustic vibrational vibrations at the frequencies of acoustic noise of various spectra or specially processed speech 1, an extended element 2 that ensures the propagation of acoustic and vibrational vibrations, fiber optic cable 3 with optical fibers 4 and a protected room 5. The source of acoustic vibration vibrations on the frequencies of acoustic noise of a different spectrum or specially processed speech 1 is connected to an extended element 2, which ensures the propagation of acoustic and vibration oscillations, which is rigidly connected with the design of the fiber-optic cable 3 along the entire length of the protected room 4. The extended element 2, which ensures the propagation of acoustic and vibrational vibrations, which can be used, for example, fiberglass, can be, as an element of the fiber optical cable 3, and simply rigidly bonded with fiber optic cable 3 along the entire length of the protected room 4.

The method is as follows. A source of acoustic-vibrational vibrations at frequencies of acoustic noise of a different spectrum or specially processed speech 1 creates vibrations that propagate along an extended element 2, which ensures the propagation of acoustic and vibrational vibrations. These vibrations due to the rigid connection of the extended element 2, which ensures the propagation of acoustic and vibrational vibrations, with the design of the fiber optic cable 3 along the entire length of the protected room 5 are transmitted to the optical fibers 4 and modulate the light streams passing through the optical fibers in both directions at different acoustic noise frequencies spectrum or specially processed speech along the entire length of the protected room 5.

In contrast to the known method, which is a prototype, the proposed method due to the distributed acoustic vibration effect on the fiber optic cable along the entire length of the protected room creates noise for leakage signals from all sections of the cable running along the room, which increases the degree of neutralization of leakage channels voice information through a fiber optic line and, accordingly, expanding the scope of the method.

LITERATURE

1. RU 2416166 C2

2. RU 2532562 C1

3. Gorshkov B.G., Paramonov V.M., Kurkov A.S., Kulakov A.T., Zazirny M.V. Distributed external impact sensor based on a phase-sensitive fiber reflectometer // Quantum Electronics, 2006, 36 (10), p. 963-965.

4. Groznov D.I., Leonov A.V., Naniy O.E., Nesterov E.T., Treshchikov V.N. “Danube” - a system for monitoring activity in the protection zone of the pipeline // Exposition Oil Gas, 4 (36), 2014, p. 51-53

5. Fiber-optic system for monitoring extended objects (oil pipelines) based on a coherent reflectometer // T-Comm, No. 1, 2014, p. 25-28

Claims (1)

A method of protecting against leakage of voice information through fiber-optic lines, which consists in creating a section on the fiber-optic line where the fiber is exposed, which modulates light streams passing through it in both directions at frequencies of acoustic noise of various spectra or specially processed speech, characterized in that they perform acousto-vibrational effects on the optical fiber along the entire length of the protected room.

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