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      In recent years, one of the most promising and developing areas of building a communication network in the world is the VOLS.

      The priority direction of the development of the transport network of Uzbekistan is the transfer of the network to the widespread use of fiber optic networks with digital transmission systems.

      This made it possible to organize reliable high-quality communication not only between the “telephone continents”, but also communication on the National Telecommunications Network of Uzbekistan. The realization of this task has become possible since 1997 after the completion of the construction and commissioning of the national segment of TAE – a large-scale international project “Trans-Asian-European VOLS”.

      In 2011, the task was to ensure the development and modernization of the telecommunications network based on the introduction of modern broadband and optical technologies, the introduction of over 950 kilometers of fiber optic lines, the expansion of the data transmission transport network to regional centers.

      Throughout the country, at the level of district centers, obsolete analog telephone exchanges have been replaced with modern digital ones. High-speed digital channels have been created on the basis of the VOLS, work is underway to expand the network and improve its reliability. The created infrastructure serves as the basis for the rapid development of wireless technologies, in particular, mobile communications. As a result, the level of coverage by the digital telecommunications network of regions, district centers and cities of the Republic amounted to 100 percent, the level of coverage by the telecommunications network of rural settlements – 95.7 percent.

      In 1999—2000, at the expense of the funds of the Cooperation Fund for Economic Development of the Republic of Korea (EDCF), technical re-equipment and development of the telecommunications network in the Andijan and Ferghana regions were carried out, a 354 km long fiber-optic line was built, switching equipment with a capacity of 46 thousand numbers was installed.

      The widespread use of fiber-optic telecommunication systems in communication networks is due to a number of their advantages in comparison with electrically cable communication systems.

      Based on this, the following main advantages of a fiber-optic line can be distinguished in comparison with electric cable communication systems:

      – huge bandwidth with transmission speeds of up to 40 Gbit/s, operating today, and over 100 Gbit/s, expected in the near future. The factors limiting the growth of transmission rates are currently the inertial properties of receivers and radiation sources. However, the use of the spectral compaction method (WDM, wave division multiplexing) increases the total transmission rate over a single fiber to several Departures/s;

      – fiber optic cables are completely unaffected by electromagnetic interference, lightning and high voltage surges. They do not create any electromagnetic or radio frequency interference;

      – ensuring complete galvanic isolation between the receiver and the information transmitter, as well as the absence of a short circuit in the transmission line;

      – the distance of information transmission for low-cost fiber-optic cables between repeaters is up to 5 km. For high-quality commercial systems, the distance between repeaters is up to 300 km. Distances close to 1000 km have been achieved under laboratory conditions;

      – the size and weight of fiber optic cables compared to all other data cables are very small in diameter and extremely light. A four-core fiber optic cable weighs approximately 240 kg/km, and a 36-core fiber optic cable weighs only 3 kg more.

      From the above it follows that the VOLS meet all the requirements of modern telecommunication communication systems. In this regard, many experts in telecommunications technologies argue that the VOLS will become the main means of transmitting information in the future. However, with the growth of the use of fiber-optic information transmission lines in telecommunication systems and their development, technical information intelligence systems are also developing, with the help of which information is secretly taken from the VOLS.

      All over the world, great attention is paid to ensuring information security – the state of security of the information environment of society, ensuring its formation, use and development in the interests of citizens, organizations, and the state.

      Therefore, the development of effective methods and technical means for the protection of information in the VOLS is one of the urgent tasks.

      Structural, mechanical and electrical technical means are usually used to protect information in the VOLS. Some of the types of protective equipment of this group are built in such a way as to complicate the mechanical cutting of the cable and prevent access to the S [1]. Similar means of protection are widely used in traditional wired networks of special communication. Also promising is the use of a pair of longitudinal power elements of the OK, which are two steel wires arranged symmetrically in a polyethylene shell, and used for remote power supply and monitoring of sensors installed in the couplings, and monitoring of ND. It is also advisable to use a kit to protect the welding site, which fills the welding site with an opaque solidifying gel. One of the proposed methods of protection is the use of multilayer optical fiber with a special structure of reflective and protective shells [2]. The construction of such a fiber is a multilayer structure with a single-mode core. The selected ratio of the refractive coefficients of the layers makes it possible to transmit a multimode control noise optical signal along the annular guide layer. There is no connection between the control and information optical signals in the normal state. Ring protection also makes it possible to reduce the level of radiation of an information optical signal through the side surface of the S (by means of leakage modes arising at the bends of the fiber

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