The development of data’s concealment and extension of the applied scope of digital steganography demand to search the compromise between concealment and capacity of the hidden
channel. In this article the relevance of redistribution in one video stream of satellite communication systems of the hidden channels capacity is justified. An approach to increasing numbers of the hidden channels in one video stream is submitted here. It can be achieved by the using of asynchronous multiplexing for hidden channels.

Despite on the fact that the SDN is actually in using, the protocols are always have experiencing some modernizations and completions. The work principles of this protocols are clearly show how the SDN working and the order of traffic handling in the network devices. This paper describes the researches of working SDN management protocol – OpenFlow. The article has a detail investigation of the network traffic transferring mechanisms in the OpenFlow – switches and processing
of the received information in the OpenFlow – switch by itself.

A detailed consideration of the method of digital video steganalysis founded on the phenomenon of linear collusion is represented in this paper. A statistical invisibility condition, which is a foundation of developing collusion-resistant embedding of the secret binary message in a digital video, is described. Tables demonstrate the results of experimental verification of the efficiency of the program written by C++. This program implements Type II collusion to delete a covert data from a digital video. Different formats and types of video, which differs from each other by number of frames per second, the rate of motion, correlation coefficients between frames, bitrate and so on, are used in this research.

This work is concerned with experimental approbation of quasi-interferometric scheme for detection of outer mechanical stress via distributed fiber optic sensor. The sensor is excited by laser source silica graded-index multimode optical fiber with great defect of refractive index profile in the center core region. We present some results of pulse response measurements performed under various stress order and various scheme configurations differing by adding fiber Bragg gratings and macrostructure defects like tapers or up-tapers.

The loss formula for optical fibers with constant radius of curvature of their axes is derived by expressing the field outside of the fiber in terms of a superposition of cylindrical outgoing
waves. In this paper we show that the bending losses of fiber modes can be calculated with the help of curvature-loss formula for slab wave guides and the validity of the result by showing that it is in agreement with the known dependence attenuation from parameters of the slab waveguide and of the LP₀₁-mode of the round step-index fiber.

Methods of driving a controlled current fed resonant inverter are considered, and methods for modulation are also given. Time diagrams are presented for the load of inverter in the self-oscillation regime. The work of inverter was investigated using the PSPICE model of nitride-gallium transistors with considering the real characteristics and modulation methods are investigated
in which the linearity of the modulation characteristic is preserved. A high efficiency of the inverter (more than 90 %) is obtained.

Currently, the technology of data transmission using visible light is considered as one of the possible solutions to the impending problem of radio frequencies spectrum crisis. Visible light communications allow combine high energy efficiency with security and high data transmission speeds. The article explores the possibility of introducing data transmission technology with
the help of visible light, and also calculates the throughput of such networks.

Article is devoted to accuracy estimation of positioning objects by mathematic Cramer Rao bound and depending on amount of base stations. Defining of coordinates is solved by rangedifference
location method. Gauss-Newton and Levenberg-Marquardt mathematic least square methods were evaluated for solving equation system.

Article is devoted to questions of the organization of adaptive multiplexing and scheduling of a traffic of multiservice networks in the channeling equipment of terrestrial stations of satellite
communication taking into account the changing interfering situation. Models of adaptive multiplexing of a multiservice traffic taking into account priorities in service and not stationarity
of the incoming information flows on the basis of Markovly the modulated Poisson processes are developed. For receiving probabilistic time response characteristics of a multiservice traffic at its multiplexing the calculation procedure to a basis of the offered models which is realized in the form of the program in the environment of MatLab is used.

The paper is devoted to theory of information security and theory of information warfare evolve. The aim of the paper is the calculation of the traffic transformation operator. Methods used:
the scientific-methodological apparatus for the research of a new cyber-attacks is based on the method of functional transformation of traffic. These new cyber-attacks can be used to test resilience and security of telecommunication systems, and to develop protection methods.

This paper analyzes WiFi access point selection mechanisms used by IoT WiFi devices. A testbed for experimental setup is proposed. The testbed includes several WiFi access points, WiFi controller and WiFi network analyzer. More than 900 measurements covering 19 test cases are made. It is shown that an received signal strength indicator is the primary criterion used by the IoT WiFi device for access point selection during connection procedure.