ANALYSIS OF OPERATING PARAMETERS OF A SOFTWARE-DEFINED NETWORK BASED ON THE OpenFlow PROTOCOL
- M.A. Buranova, Povolzhskiy State University of Telecommunications and Informatics (PSUTI), department of information security, associate professor, Ph.D.; buranova-ma@psuti.ru
- V.G. Kartashevskiy, PSUTI, head of the department of information security, professor, Dr.Sci.(Tech.); kartashevskiy-vg@psuti.ru
- A.S. Muthanna, The Bonch-Bruevich Saint-Petersburg State University of Telecommunications, department of communication networks and data transmission, associate professor, Ph.D.; ammarexpress@gmail.com
Keywords: queue model, software-defined network, SDN, quality of service, hyperexponential distribution, average service time for a request in the system.
The paper presents the results of the analysis of the quality of service (QoS) of traffic obtained during the processing of request flows in a software-defined network (SDN). It has been established that in the high load mode (the load factor tends to unity) significant correlations arise in the sequence of time intervals between packets. Analytical expressions are obtained for estimating the average values of packet delay time, delay variation, and queue length in the case of an SDN network node represented by the M/D/1 and H2/D/1 models. A technique for estimating the QoS parameters of traffic in SDN has been developed.
AN EFFICIENT METHOD OF MULTIPATH TRAFFIC ROUTING IN THE INTERNET OF THINGS
- S.N. Bushelenkov, PJSC Rostelecom, North-West macro-regional branch, The Bonch-Bruevich Saint-Petersburg State University of Telecommunications, department of communication networks and data transmission, postgraduate; bsn1980@yandex.ru
Keywords: Internet of Things, IoT, high density network, multipath routing, route, data transfer rate, optimization.
The article presents the results of the study of the dependence of the transmission speed in the Internet of Things (IoT) when using multipath routing. The paper shows that the choice of routes for data transmission is a problem for which numerical optimization methods can be used. It is proposed a method for the selection of the group of routes and traffic distribution coefficients, which makes it possible to increase the efficiency of their application. The proposed method is implemented using dynamic programming.
GENERALIZED MODEL OF THE FUNCTION OF A DECAMETER RADIO NETWORK WITH THE PSEUDO-RANDOM TUNING OF OPERATING FREQUENCIES
- R.S. Panin, S.M. Budyonny’s Military Academy of Communications, adjunct; paninrs@yandex.ru
- A.N. Putilin, PJSC Inteltech, Scientific and technical centre, chief researcher, professor, Dr.Sci.(Tech.); PutilinAN@inteltech.ru
Keywords: decameter radio communication, pseudo-random tuning of operating frequency, multiple access algorithms, frequency resource.
The article discusses the features of radio networks in the decameter range with the collective use of a frequency spectrum. The mode of pseudo-random tuning of the operating frequency with time-frequency division of radio channels of different subscribers is investigated. It is proposed the algorithm for joint optimization of the choice of operating frequencies and parameters of the multiple access algorithm in a decameter radio communication network, which provides a significant increase in the efficiency of the decameter radio communication network in the group usage of a frequency resource. The practical result of this work determines the possibility of automating the process of preparing radio data in an automated communication control system.
METHODOLOGY OF NATURAL TESTS OF GMDSS COASTAL OBJECTS OF THE SEA AREA A2
- V.V. Gromozdin, FSUE NIIR — Testing Centre OMEGA, deputy director of the branch for technical development, Ph.D.; gromozdin@niir.ru
- V.I. Kovalenko, FSUE NIIR — Testing Centre OMEGA, the scientific and technical department of marine and aviation equipment, lead engineer; kovalenko@niir.ru
- K.V. Ievlev, FSUE NIIR — Testing Centre OMEGA, the scientific and technical department of marine and aviation equipment, first category engineer; ivlev@niir.ru
- M.S. Kozub, FSUE NIIR — Testing Centre OMEGA, head of the scientific and technical testing department; kozub@niir.ru
Keywords: field tests, midrange maritime radio communication, signal-to-noise ratio, field strength, radio receiver sensitivity, electromagnetic compatibility, Global Maritime Distress and Safety System, GMDSS, sea area A2.
The methodology for conducting field tests of coastal facilities (stations) of the Global Maritime Distress and Safety System of sea area A2 is considered. The threshold values of electromagnetic field intensity on the vessel side and electromotive force at the input of radio receivers at the coastal facility were calculated on the basis of typical parameter values. The actual provision of electromagnetic compatibility during the operation of closely spaced transmitting devices and the maximum possible levels of external atmospheric and industrial noise are taken into account.
PROTECTION RATIOS FOR DRM DIGITAL AUDIO BROADCASTING SYSTEM IN THE VHF BANDS
- S.A. Sokolov, LLC Digiton Systems, general director; sokoloff@digiton.ru
- S.V. Myshyanov, The Bonch-Bruevich St. Petersburg State University of Telecommunications (SPbSUT), scientific and educational centre Technologies of information and educational systems, director; mishyanov@gmail.com
- Yu.A. Kovalgin, SPbSUT, professor emeritus, Dr.Sci.(Tech.); kowalgin@sut.ru
Keywords: digital audio broadcasting, protection ratios, Digital Radio Mondiale, DRM, FM, DRM-FM, D/SECAM, VHF band.
The measurement results of the basic protection ratios for the DRM digital audio broadcasting system interacting with FM broadcasting and D/SECAM analog television signals in the 65.9−74 and 87.5−108 MHz frequency bands are presented. Based on ITU-R documents, test signals and methods for measuring protective ratios are proposed. It is investigated the possibility of implementing coverage areas of the same size when transmitting analog FM and digital DRM broadcasting signals in a common radio channel.
METHOD OF PROTECTING DIGITAL DATA TRANSMISSION SYSTEMS FROM SINGLE AND DOUBLE ERRORS
- A.A. Pavlov, Branch of the Military Academy of the Strategic Missile Forces named after Peter the Great (MASMF), professor, Dr.Sci.(Tech.); Pavlov_iif@mail.ru
- A.N. Tsarkov, Interregional Public Institution «Institute of Engineering Physics» (IEP), president-chairman of the board, professor, Dr.Sci.(Tech.); info@iifrf.ru
- Yu.A. Romanenko, Branch of the MASMF, leading researcher, professor, Dr.Sci.(Tech.); info@iifrf.ru
- A.Yu. Romanenko, IEP, researcher, Ph.D.; info@iifrf.ru
- M.I. Makeev, Branch of the MASMF, researcher; info@iifrf.ru
- F.A. Pavlov, Branch of the MASMF, researcher; info@iifrf.ru
Keywords: correcting linear code, information bits, check bits, error syndrome, single and double errors, information redundancy.
It is described the regular procedure for coding information for correcting single errors and detecting double errors while reducing information redundancy by one check bit. Thus, it is possible to reduce the hardware costs associated with storing check bits values in a memory device. There were revealed regularities allowing to generate the additional checks of error signs during decoding. Thanks to this, it is possible to determine erroneous bits when indistinguishable error syndromes are caused by the reduction of the main check digits. It has been found that the implementation of the proposed method for code (15,11) helps to detect and correct 100% of single errors, detect 100% and correct 27% of double errors, using one check bit less than for a modified Hamming code.
DEFINITION OF THE LAW OF PULSE-WIDTH MODULATION WITHOUT AUXILIARY SIGNALS
- N.V. Lemeshko, JSC Corporation Cometa, head of a department, Dr.Sci.(Tech.); nlem83@mail.ru
- S.S. Zaharova, High School of Economics, teacher, Ph.D.; ZaharovaSvetlana@yandex.ru
Keywords: pulse-width modulation, telephone communication, modulation law, error, modulation law, normalization.
The article proposes a method for determining the law of pulse-width modulation (PWM) directly from the output signal of the modulator. The main sources of errors in the formation of signals with PWM are analyzed, and a typical range of measured parameters is presented. A description of the method for determining the PWM law based on mathematical operations on the output signal of the modulator is given. Examples of the implementation of such an algorithm confirming its viability are presented. The features of using the proposed approach when using the built-in mathematical processing functions of modern oscilloscopes are revealed.
DEVELOPMENT OF INFORMATION SERVICES FOR MONITORING THE PUBLICATION ACTIVITY OF EMPLOYEES OF A SCIENTIFIC ORGANIZATION
N.B. Bakanova, Keldysh Institute of Applied Mathematics RAS, leading researcher, associate professor, Dr.Sci.(Tech.); nina@keldysh.ru
Keywords: design of information systems, monitoring of scientific activity, publication activity.
The article is devoted to the creation of information services for monitoring the publication activity of employees of a scientific organization, reflecting the effectiveness of scientific research. The article deals with the problems of accumulating data on publications of employees, reflecting data in the information base for the study of these data based on scientometric indicators.
ACHIEVABLE MARGINAL EFFICIENCY OF ERROR-CORRECTING BINARY CODES
- A.S. Adzhemov, Moscow technical university of communications and informatics (MTUCI), president-chairman of the Board of Trustees, professor, Dr.Sci.(Tech.); asa@mtuci.ru
- N.Yu. Albov, MTUCI, postgraduate
Keywords: code construction, minimum code distance, noise immunity, coding efficiency, theoretically accessible boundary, error-correcting codes.
The digital representation of various signals makes it possible to apply error-correcting codes at subsequent stages of their transmission, which provide protection against possible errors arising from interference in the communication channel. At the same time, it is important that these codes have the maximum possible rate for the required corrective ability. The article presents the results of calculations for linear codes, showing their realistically achievable limiting capabilities.
