Kharin O. Methods and means of integrated protection of information in telecommunication systems with multiple access based on data factorial coding

The dissertation is aimed at solving the actual scientific and technical problem of increasing the reliability of data transmission and ensuring their integrity using factorial codes that provide integrated protection of information (simultaneous protection against communication channel errors and protection against unauthorized modification and / or unauthorized access). This task includes the factorial codes improvements, create a method of construction of telecommunication systems that use these codes and have new features such as error correction with losses and dynamic allocation of resources between users of the system in real-time. The paper analyzes the existing methods of factorial coding, including factorial code with data recovery by permutation, which showed that they are vulnerable to errors pair multiplicity which leading to a transformation of a permutation of the allowed set to another permutation, owned by the same set. To increase the robustness of factorial codes to even multiplicity errors, the task of the research is to develop the methods for improving the reliability of data transmission in systems with inseparable factorial coding. Another area of research related to factorial coding is the process of forming a signal-code structure for inseparable methods of factorial coding, in particular, factorial code with data recovery by permutation. The following task of the dissertation is to develop the method of construction of signal-code structure for systems with factorial code with data recovery by permutation. Methods of coding based on convolutional codes and methods based on cascading codes are analyzed. Analysis convolutional codes showed that formed coding sequence contains unprotected information symbols. Also, convolutional codes have speed code which no more than 1/2. At the same time, cascading codes, through the consistent use of several codes, can solve the problem of protecting information from unauthorized reading, but they add additional redundancy and also increase hardware costs. The performed analysis allows to clearly formulate the next task of the research, which is to develop a methods of decoding of factorial code with data recovery by permutation for real-time telecommunication systems. The analysis of existing methods of construction of telecommunication systems with multiple access based on multiplexing of packets and time distribution is made. An analysis of these methods showed that most of them involve the availability of service data to implement a reservation/ release mechanism of time slots for data transmission, which reduces the overall bandwidth of the channel. Also, these methods do not implement a single procedure for providing integrated information security. The results of the analysis made it possible to define clearly the tasks of the research to develop a method of construction of multiple access systems based on inseparable factorial coding. As part of the research a new methods of improving the reliability of data transmission systems with factorial coding with data recovery by permutation were developed, which allows to increase the capacity of inseparable factorial codes to detect errors by adding of additional bits signs to the permutation and combining of the noise immunity codes. At first time a method of forming a code signal design for systems with factorial coding of data recovery permutation has been developed. It allowed to maximize speed of code for a given level of reliability data and the corresponding minimum distance between the nodes by constructing arrays of high density arrangement of signal vectors. In addition, the method of factorial coding with permutation data recovery has been further developed, which by data recovery with loss based on Hemming's metric or linear interpolation method allows protecting speech information from communication channel errors and unauthorized access in real-time telecommunications systems. The block diagrames of the decoding devices and the algorithmes for error correction in the Hamming metric and by the method of linear interpolation are developed. In the final part of the dissertation research at first time a method of building multiple access systems based on inseparable factorial coding has been developed, which provides integrated protection of information and as well as cyclic synchronization on a working signal. The structural scheme and algorithm of operation of the multiplexer of communication channels on the basis of the factorial codes are developed. The block diagram of telecommunications system with multiple access using the multiplexer of communication channels on the basis of the factorial codes and the algorithm of network resources management also have been developed.