Information and Telecommunication Sciences

INDICATORS OF INFORMATION FEATURES FOR RECOGNISING THE STATE OF SOURCES AND OBJECTS OF TELECOMMUNICATION NETWORKS AND SYSTEMS

Аnatolii Ilnytskyi, Tsukanov Oleg — Thu, 21 Dec 2023 00:00:00 +0200

Background. The majority of modern procedures for the recognition of radio sources and objects are based on the use of binary and multivalued logic, which have low specific features. The essence of the issues is to compare a priori knowledge and a posteriori data coming from the surveillance means and to make a decision on the recognition of a radio emission object. A priori knowledge and a posteriori data are formed both before and during the recognition process on the basis of sets of information features or information signatures. At the same time, when constructing an integral indicator for determining the affiliation and status of sources and objects, it is necessary to know the weighting coefficients of information features, the determination of which is a rather difficult task. Therefore, the issue of determining the weighting coefficients that characterise information features remains an urgent task in the field of statistical radio engineering.

Objective. The purpose of the paper is to select and substantiate a simple and effective method for calculating the weighting coefficients of information features for the implementation of the methodology for recognising radio sources and objects.

Methods. Decision-making on the value of the weighting coefficients of information features of the recognition objects belonging to a certain class is based on the results of calculations using one of the three Fishburne formulae, which, in comparison with the known methods of expert assessments, are very simple and understandable, do not require any additional research and complex calculations.

Results. The procedure is proposed and an example of using the Fishburne method (three formulae) in calculating the value of the weighting coefficients of information features for recognising sources and objects of radio monitoring is considered.

Conclusions. Comparison of the method of calculating the weighting coefficients using Fishburne's formulae with other known methods of expert assessments shows that there is no need to interview experts and process their analysis results; there are no restrictive implementation conditions; it is easy to take into account additional information about the indicators, if necessary; no software implementation with a complex search algorithm is required; it is easy to make any changes as additional information indicators.

POSSIBILITIES OF IMPROVING THE VOICE SERVICES QUALITY IN 5G NETWORKS

Vetoshko Ivan, Serhii Kravchuk — Thu, 21 Dec 2023 00:00:00 +0200

Background. The introduction of fifth-generation (5G) networks creates new opportunities for fast and continuous data exchange, but there are still some problems with the quality of voice services in such networks. With the rapid development of technology and the further spread of 5G, there is a need to understand the impact of key aspects of 5G on voice quality. This requires research that can systematically analyse the features of 5G networks that affect the quality of voice services.

Objective. Identification of ways to improve the quality of voice services in 5G networks. Assessment of key indicators of voice service quality in 5G networks. Determination of the best option for the gradual transition to the Standalone mode and the use of VoNR technology in the fifth generation networks.

Methods. Analysis of factors affecting the quality of voice services in fifth-generation networks. Analysis of well-known publications on the implementation of 5G networks. Comparison of the implementation of Non-Standalone and Standalone modes in the 5G network. Testing of the modern EVS codec, which provides an opportunity to improve the customer experience.

Results. Confirmation that 5G networks can significantly improve the quality of voice services compared to previous mobile communication technologies such as 4G and 3G. Certain factors that may affect the quality of voice services and require additional attention when planning and deploying 5G networks are identified. The optimal steps for the transition to the Standalone mode and the use of VoNR technology in fifth-generation networks are determined. The main differences in the QoS architecture between LTE and 5G are identified, and the purpose of DRB flows for separating traffic types and services is established.

Conclusions. It has been confirmed that 5G networks can significantly improve the quality of voice services compared to previous technologies such as 4G and 3G. This is possible due to the broadband capabilities of 5G networks, improved data transmission, low latency, the use of an advanced EVS codec and reduced response time. However, certain factors, such as network coverage, optimisation level and traffic characteristics, can affect the quality of voice services and require additional attention when planning and deploying 5G networks. The QoS management architecture consists of QoS flows, which allow separating packet assignment to flows (managed by the CN) from the assignment of DRB flows (managed by the RAN). As 5G networks are being rolled out gradually, it is important to properly integrate the 5G domain into the existing telecoms provider's network. The transition from Non-Standalone to Dual connectivity is a necessary step for the implementation of VoNR technology in Standalone mode. Using the modern EVS codec allows not only improving the customer experience, but also introducing new voice services.

TWO-FACTOR AUTHENTICATION PROTOCOL IN ACCESS CONTROL SYSTEMS

Irina Strelkovskaya, Oleksiy Onatskiy, Larysa Yona — Thu, 21 Dec 2023 00:00:00 +0200

Background. To ensure the protection of the biometric access control system used in unsecured communication channels, it is necessary to exclude the storage and transfer, transfer of biometric data as well as sequences generated on their basis. The paper proposes a cryptographic protocol of two-factor authentication with the zero-knowledge over the extended field GF(2^m) on elliptic curves using biometric data and the private key of the user.

Objective. The aim of the article is to develop a cryptographic protocol for zero-knowledge two-factor authentication based on elliptic curves using biometric data and the user’s private key, which allows increasing cryptographic strength and reducing the duration of the authentication process.

Methods. The process of implementing zero-knowledge proof protocols is as follows: one user (proofer) can convince another user (verifier) that he has some secret without disclosing the secret itself.

Results. A cryptographic protocol for two-factor authentication with zero-knowledge over the extended field GF(2^m) of elliptic curves using user biometric data is proposed, which significantly reduces the size of the protocol parameters and increases cryptographic strength (computational complexity of the breaking). There is no leakage of private key information and biometric data of the user during the execution of the zero-knowledge proof protocol.

Conclusions. The implementation of a cryptographic protocol with zero-knowledge proof two-factor authentication based on elliptic curves allows significantly reducing the size of protocol parameters and increasing the cryptographic strength (computational complexity of the breaking).

ADJUSTING THE PARAMETERS OF MACHINE LEARNING ALGORITHMS TO IMPROVE THE SPEED AND ACCURACY OF TRAFFIC CLASSIFICATION

Andrii Astrakhantsev, Larysa Globa, Andrii Davydiuk, Oleksandra Sushko — Thu, 21 Dec 2023 00:00:00 +0200

Background. Telecommunications developments lead to new mobile network technologies and especially 5G, which has only recently been launched, sixth generation of which is already under active development. The development of new technologies influence on both types of mobile traffic (V2V, IoT) and leads to the significant increase in the volume of existing traffic types. Currently, existing methods of traffic processing are not adapted to such changes, which may lead to a deterioration in the quality of service.

Objective. The purpose of the paper is to analyze the effectiveness of machine learning algorithms to solve the task of traffic classification in mobile networks in real time.

Methods. The method of solving the problem of increasing the efficiency of information processing is the introduction of new algorithms for traffic classification and prioritization. In this regard, the paper presents the urgent task of analyzing the effectiveness of machine learning algorithms to solve the task of traffic classification in mobile networks in real time.

Results. Comparison indicated the best accuracy of the ANN algorithm that was achieved with the number of hidden layers of the network equal to 200. Also, the research results showed that different applications have different recognition accuracy, which does not depend on the total number of packets in the dataset.

Conclusions. This proceeding solves the urgent problem of increasing the efficiency of the mobile communication system through the use of machine learning algorithms for traffic classification. In this regard, it can be concluded that the most promising is the application of algorithms based on ANN. In future the aspect of anomaly detection based on traffic classification and traffic pattern preparation should be investigated, as this process allows detecting attacks to network infrastructure and increase mobile network security.

OPTIMIZING HARD QOS AND SECURITY WITH DISJOINT PATH ROUTING

Oleksandr Lemeshko, Oleksandra Yeremenko, Maryna Yevdokymenko, Batoul Sleiman — Thu, 21 Dec 2023 00:00:00 +0200

Background. The combination of secure routing and hard QoS is a worthwhile topic that involves designing and implementing network protocols and systems that can provide high performance and robust protection for data flow due to shared goals. Secure QoS routing over disjoint paths is a challenging problem that requires balancing the trade-off between network security and bandwidth guarantees.

Objective. This article investigates a mathematical model that can address secure QoS routing by formulating it as an optimization problem with a linear objective function and linear or bilinear constraints. The objective function aims to minimize the paths compromise probability, while the constraints ensure that the total bandwidth of the paths meets the QoS requirements.

Methods. We use computer simulation of hard QoS and security with disjoint path routing. Also we use mathematical programming methods in order to describe secure QoS routing.

Results. The article presents a numerical study of the model using different scenarios and parameters. The results show that the model can effectively provide secure QoS routing over disjoint paths with a high bandwidth guarantee level and a low compromise probability. The work analyses the sensitivity of the solutions to the QoS requirements and reveals that there is usually some margin in the bandwidth provision.

Conclusions. The proposed model is a promising tool for secure QoS routing over disjoint paths in various network environments.

PRUNING MINIMUM SPANNING TREES AND CUTTING LONGEST EDGES TO CONNECT A GIVEN NUMBER OF NODES BY MINIMIZING TOTAL EDGE LENGTH

Vadim Romanuke — Thu, 21 Dec 2023 00:00:00 +0200

Background. Whereas in many tasks of designing efficient telecommunication networks, the number of network nodes is limited, the initial choice of nodes is wider. There are more possible locations than factually active tools to be settled to those locations to further satisfy consumers. This induces an available node constraint problem.

Objective. Given an initial set of planar nodes, the problem is to build a minimum spanning tree connecting a given number of the nodes, which is less than the cardinality of the initial set. Therefore, the available node constraint problem aims at building an optimally minimum spanning tree to connect a given number of planar nodes being less than an initial number of nodes by minimizing the tree length.

Methods. The initial set of nodes is triangulated. This gives a set of edges, whose lengths are calculated and used as graph weights. A minimum spanning tree is built over this graph. The desired number of nodes is reached by pruning the minimum spanning tree connecting the initial number of nodes, where free edges whose weights are the largest are iteratively removed from the tree. The other approach, the cutting method, removes longest edges off the initial minimum spanning tree, regardless of whether they are free or not.

Results. Unlike the pruning method, the method of cutting longest edges may result in a minimum spanning tree connecting fewer nodes than the desired number. However, the cutting method often outputs a shorter tree, especially when the edge length varies much. Besides, the cutting method is slower due to it iteratively rebuilds a minimum spanning tree.

Conclusions. The problem is initially solved by the pruning method. Then the cutting method is used and its solution is compared to the solution by the pruning method. The best tree is shorter. A tradeoff for the nodes and tree length is possible.

MINIMIZING HIGH-FREQUENCY SWITCHING LOSSES IN WIDEBAND GAN HEMTS FOR FLYBACK CONVERTERS

Dmytro Arseniuk, Yuri Zinkovskyi — Thu, 21 Dec 2023 00:00:00 +0200

Background. In the realm of pulse power supplies, flyback converters play a pivotal role in efficient voltage conversion and providing electrical isolation. Typically, these converters utilize silicon transistors. However, they encounter several issues that hinder their energy efficiency and operational stability. A primary concern is the increase in switching losses at high frequencies. This is attributed to the lower switching speed and higher on-state resistance characteristic of silicon transistors. Such inefficiency leads to substantial power dissipation, thereby reducing overall efficiency. Additionally, the heat generated from these losses necessitates complex temperature control systems, increasing operational burden and affecting the reliability and longevity of the converters. Furthermore, the operational frequency of these converters is limited. While operating at higher frequencies is beneficial for reducing the size of passive components, it exacerbates the problems of switching losses and heat dissipation in silicon transistors.

Objective. This article aims to conduct a comprehensive study and optimization of flyback converters based on High Electron Mobility Transistors (HEMT) made of Gallium Nitride (GaN), focusing on minimizing losses in high-frequency switching. The study delves into the intrinsic properties of GaN HEMTs, highlighting their superior characteristics compared to traditional silicon counterparts, and emphasizes the circuit design methods for minimizing losses and their features.

Method. The research involved a detailed analysis of the switching losses of GaN HEMTs under high-frequency switching conditions. Using computer simulation models, the study examines the impact of various parameters, such as currents and voltages on the GaN transistor, power dissipation, and the output characteristics of the device with different circuit topologies on the performance and efficiency of switching.

Results. The results provide insights into the optimization strategies of topology, particularly the use of transistor gate drivers and snubber circuits, which are crucial for enhancing the overall efficiency and reliability of flyback converters.

Conclusions. The article offers an in-depth analysis into optimizing high-frequency flyback converters using GaN HEMTs, providing valuable guidance for devices requiring compact power sources, such as in small aircraft systems and telecommunications networks.

AUTOMATED WORKFLOWS FOR ASSESSING THE QUALITY OF FUNCTIONING OF SCIENTIFIC AND EDUCATIONAL INSTITUTIONS

Rina Novogrudska, Eduard Siemens, Andrii Pidnebesnyy, Yegor Shelest — Thu, 21 Dec 2023 00:00:00 +0200

Background. The effectiveness of functioning is a particularly important characteristic for organizations involved in the field of science and education, since the future level of state development and the life of its citizens depends on the quality of the services they provide. There are certain generally accepted principles of such organizations evaluation that is set by relevant normative documents. Nowadays important tasks are optimization and automatization of such processes.

Objective. The aim of the paper is to propose and develop a workflow model for automating and optimizing the procedure for evaluating scientific and educational institutions.

Methods. We use approaches to business process modelling and basic principles of workflow modelling, namely BPMN notation was chosen as the notation to model elements of workflows for assessing the quality of scientific and educational institutions functioning, and Camunda Modeler was used as the development environment.

Results. Conceptual model of the work process for assessing the quality of scientific and educational institutions functioning was proposed, which made it possible to generalize and formalize such an assessment process. Developed using BPMN models of workflow were used to test proposed conceptual model and prove its effectiveness for automating the process of assessing the quality of scientific and educational institutions functioning.

Conclusions. Mechanism of modelling the process of assessing the quality of scientific and educational institutions functioning proposed in the paper gave basis and means for such process optimization and automatization.