Software & Systems

Articles of journal № 4 at 2022 year.

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1. DIY DDoS Protection: operational development and implementation of the service in the National Research Computer Network of Russia [№4 за 2022 год]
Author: Abramov A.G.
Visitors: 2489
Nowadays, the protection of digital infrastructures of organizations and end users from constantly growing in number and becoming more sophisticated cybersecurity threats is receiving increased attention at various levels. An extremely important task is to ensure reliable and effective protection of critical infrastructures of large telecommunications companies. One of the most common types of cybersecurity threats is Distributed Denial of Service (DDoS) performed at different levels of network interaction, from infrastructure to applica-tions, and aimed at different resources and services. This paper provides an overview of modern methods and technologies to prevent and mitigate DDoS at-tacks with an emphasis on protecting the networks of telecom operators and their users. It also discusses such methods as BGP Blackhole and BGP FlowSpec based on dynamic routing mechanisms and protocols, as well as the methods based on network traffic intelligent analysis and filtering by specialized cleaning sys-tems. The main technical requirements, quality criteria and some quantitative characteristics of DDoS pro-tection solutions are outlined. There are examples of commercial and freely distributed systems. A separate section of the paper is devoted to a detailed description of a relatively simple service for pro-tecting against DDoS attacks. The service is developed and put into operation by specialists of the National Research Computer Network of Russia (NIKS) based on real-time processing and analysis of NetFlow data collected from boundary routers and on the BGP FlowSpec protocol. The is also general information about the hardware and software complex, architecture and main components of the service, involved software packages and technologies along with some statistical data on the results of detecting DDoS attacks in the NIKS network infrastructure.

2. System software for redundancy management of avionics complexes [№4 за 2022 год]
Authors: Ageev A.M., Novitsky L.V., Tsvetkov E.S., Shurman V.A.
Visitors: 1069
The paper presents the main results on the substantiation of functions, algorithms, software structure and features of the practical implementation of redundancy management system software (RMSS) intended for implementation in advanced avionics complexes. The authors use a method of managing the reconfiguration of heterogeneous redundant resources of on-board equipment based on configuration supervisors that are special software objects, each of which is cor-related with a specific configuration of equipment and performs all the procedures for preparing and imple-menting this configuration. The paper describes the main provisions of the developed approach based on configuration supervisors. It also presents the information structure of supervisors including a readiness buffer, configuration tables and functional efficiency indicators, monitoring modules, configuration arbitration, mode formation, man-agement, as well as auxiliary and buffer files. There is a presentation of the supervisor arbitration procedure including the stages of intercomputation and intersupervisory arbitration. The paper defines RMSS tasks and functions consisting in monitoring the condition, forming readiness indices and indicators of functional effi-ciency of configurations, adaptation to the complex operating modes, selection and implementation of con-figurations. The proposed RMSS structure includes a global, an external and internal levels implemented through configuration tables, executive procedures and buffer auxiliary files. The main features of the prac-tical implementation of RMSS in the onboard computing environment of integrated avionics with a real-time operating system are formulated. The proposed solutions and algorithms can be used in forming re-quirements and designing promising fault-tolerant on-board complexes with an excessive number of hetero-geneous resources, in developing appropriate on-board software.

3. Development of trusted microprocessor software models and a microprocessor system [№4 за 2022 год]
Authors: S.I. Aryashev , Grevtsev N.A., P.S. Zubkovsky , Chibisov P.A., Kuleshov A.S., Petrov K.A.
Visitors: 1971
When developing a trusted microprocessor for digital SCM control systems (systems with a critical mission), it is necessary to develop a software model (emulator) of a trusted microprocessor and a system emulator based on it to approve the architectural model and to study the possibilities of parrying threats. Instruction-based and behavioral microprocessor emulators are tools for modeling the microprocessor architecture and the system as a whole. They play a fundamental role in various areas of microarchitecture design. Emulators are used as a reference model for functional verification and for assessing the contribution of new ideas in-troduced by developers at the microarchitecture level to the performance of the system as a whole, as well as for understanding the behavior of user programs and identifying hardware elements that limit the system ef-fectiveness. The paper presents the criteria necessary for creating trusted systems, a developed instruction-based emulator of the trusted microprocessor microarchitecture (vmips), as well as a behavioral emulator of the microprocessor system architecture (QEMU) based on a trusted microprocessor to approve the architectural model and study the possibilities of parrying threats. There is a demonstration of software that tests the functions of the emulator to ensure the fulfillment of the system’s trusted execution environment criteria by parrying threats from the FSTEC information security threats data bank. The paper also describes launching a demonstration task in a virtual environment on a virtual programmable logic controller with a trusted microprocessor using SCADA for monitoring and con-trol. Using a virtual PLC with a virtual environment allows testing and debugging, conducting security studies, building models of existing and future nodes, working out various scenarios, and getting complete infor-mation about the work progress. Preliminary testing in a virtual environment also allows reducing the risks of commissioning and working out various threat models and their parrying before developing a microproces-sor. Based on the results of the work performed, the development of a trusted microprocessor with a MIPS-like architecture for digital control systems of the SCM is planned in the future.

4. A software computing suite for simulating effects from coronating wires of overhead AC lines [№4 за 2022 год]
Authors: Balametov A.B., Khalilov E.D., Isaeva T.M.
Visitors: 1538
Due to the development of electrical networks of high and extra-high voltage and ultra-high voltage, the is-sues of the environmental impact of high-voltage power lines are becoming relevant. There is an urgent need to develop software for assessing (monitoring) the electromagnetic compatibility of overhead lines. It will make it possible to assess the impact of high voltage AC transmission lines on the environment. The paper considers mathematical modeling of the influence of overhead line wires, electromagnetic in-terference, corona discharge, radio interference in wires. It also describes a developed program for calculat-ing power and energy losses due to corona in overhead lines of ultra-high AC voltage. To calculate the ca-pacitance of overhead line phases, there is a method for determining the working capacitance of wires for a horizontal arrangement of wires and two grounded cables. There is a developed electromagnetic compatibility software to use for taking measures aimed at reduc-ing the electric field of extra-high voltage overhead lines. The paper gives the example of overhead lines with 500 kV voltage, which presents the results of a com-plex system for modeling corona losses, electric field voltage and active energy losses due to radio interfer-ence.

5. A GraphHunter software tool for mapping parallel programs to a supercomputer system structure [№4 за 2022 год]
Authors: Baranov, A.V., Kiselev E.A., P.N. Telegin, Sorokin A.A.
Visitors: 1970
One of well-known problems in high-performance computing is optimal mapping of parallel program pro-cesses to supercomputer system nodes. A solution for this problem minimizes the overhead for information exchanges between the processes of a parallel program and thus increases the performance of calculations. When solving a mapping problem, both a supercomputer system and a parallel program are represented as graphs. The paper shows solving the mapping problem in relation to a system for collective use of a supercom-puter that handles a queue of parallel programs. After passing the queue, a new previously unknown subset of supercomputer nodes is allocated to the parallel program. In this case, it is necessary to construct a graph of a selected subset of nodes and find a suitable mapping of the parallel program onto this graph in a rea-sonable time. It is suggested to run parallel mapping algorithms on the supercomputer nodes allocated for parallel program. To study the properties of mapping algorithms, the GraphHunter software tool was developed. This tool makes it possible to conduct experiments with three parallel algorithms: simulated annealing, genetic algo-rithm, and their combination. This article discusses the structure of the GraphHunter software tool, and pre-sents the results of experiments with GraphHunter runs on the MVS-10P OP supercomputer at the Joint Su-percomputing Center of the Russian Academy of Sciences.

6. Modelling a supercomputer job bundling system based on the Alea simulator [№4 за 2022 год]
Authors: Baranov, A.V., D.S. Lyakhovets
Visitors: 2635
Modern supercomputer job management systems (JMS) are complex software using many different sched-uling algorithms with various parameters. We cannot predict or calculate the impact of changing these pa-rameters on JMS quality metrics. For this reason, researchers use simulation modelling to determine the op-timal JMS parameters. This article discusses the problem of developing a supercomputer job management system model based on the well-known Alea simulator. The object of study is our scheduling algorithm used for developing the supercomputer job bundling system. The algorithm bundles jobs with a long initialization time into groups (packets) according to job types. Initialization is performed once for each group, and then the jobs of the group are executed one after the other. By using a bundling system, it is possible to reduce the initialization overhead and increase the job scheduling efficiency. We implemented the bundling algorithm as a part of the Alea simulator. We have done comparative simulation of implemented algorithm for various workloads. The comparison involved the FCFS and Backfill scheduling algorithms built into Alea. Several workloads with different intensities were generated for the simulation. The minimum job initialization share thresholds for these workloads were determined based on the simulation results. The bundling system noticeably im-proves the scheduling efficiency compared to the FCFS and Backfill algorithms starting from these thresh-olds. The study results showed that the developed simulation model could be used as a software tool for a comparative analysis of various algorithms for supercomputer job scheduling.

7. Developing the Expert system as a tool to form encyclopedias and to fill the Common digital space of scientific knowledge [№4 за 2022 год]
Authors: S.A. Vlasova, N.E. Kalenov , A.N. Sotnikov
Visitors: 1938
The article reflects the results of work on the development of a universal customizable WEB-based expert system designed to distinguish from a variety of objects those that meet the specified criteria to the maxi-mum extent. Authorized experts, who are selected based on structured data characterizing them, which are entered into the system when registering an expert, assess each object. The system can be used for expert selection of any objects whose properties are presented in digital form, and the formulated assessment criteria are determined by these properties. The task of expert selection of objects of various kinds is one of the most important in the formation of the content of the Common digital space of scientific knowledge (CDSSK). The concept of including printed materials in CDSSK is based on the principle of point reflection (but with deep semantic text markup) of the most important fundamental publi-cations in each scientific field. The selection of such publications should be based on the expert opinion of leading experts in this field of knowledge. It is also necessary to use the principle of expert selection when deciding on the creation of 3D models of museum objects as well as reflections in the CDSSK of film, photo and audio materials. The Expertise sys-tem can be used for selecting publications to be included in the National Electronic Library (NEL); for select-ing authors of articles for the Great Russian Encyclopedia; for reviewing articles submitted to the editorial offices of scientific journals; for reviewing articles submitted to the editorial boards of scientific journals; for conducting contests of scientific papers, photographs, video materials and other objects, the evaluated prop-erties of which can be presented on the Internet. Compared to the previous version of the system, the description of which was published in 2020, the new version presented in this article has more flexible configuration tools. It can be configured to the expert re-view of various object groups. The objects of each group are assessed according to their own criteria using their own rating system. By group is meant fundamental monographs published in different years related to the same scientific field; articles proposed for publication in a particular journal; a group of specialists who have expressed a desire to act as authors of commissioned scientific articles, databases reflecting objects of the same type, etc. Each group has its own system of object assessment and own circle experts. The result of the system operation is various rating lists of objects based on processing expert assess-ments. The system also has a special built-in application that allows a user with the “administrator” status to analyze rating lists and the activity of experts. The article provides a detailed description of the system struc-ture, its functionality, and examples of its use.

8. Modelling of deformation of elastic objects using perturbation functions [№4 за 2022 год]
Authors: Vyatkin, S.I., Dolgovesov, B.S.
Visitors: 1308
The paper presents a method for modelling the deformation of elastic objects using perturbation functions. It describes deformations of elastic materials capable of stretching in such a way as to return to their original shape and size when releasing force. The method uses second-order differential equations and operator functions in exponential integration. As a result, the calculation time decreases and the overall accuracy in-creases. The method is easily parallelized and allows visualizing complex realistic models. Due to parallel processing and the absence of the need to transfer a large amount of data from the shared memory to the GPU memory, the visualization speed increases compared to the option that uses CPU only. The second paragraph considers a way of defining objects that is different from the polygonal descrip-tion. A basic shape and a set of perturbations are used to define an object. This approach allows reducing memory costs and improving image quality. The third paragraph lists the tasks that solved when modelling animation and deforming bodies using the elastodynamics equations. The paper describes the adaptation of the elastodynamics equations for expo-nential integration. Exponential methods are well suited for rigid systems when solving complex problems. For a rigid system, the authors use a time integrator on the scale of the object general movement with suffi-cient accuracy. There is a description of the exponential processing when sampling a time variable over a certain interval. Exponential integration is constructed using quadrature for a nonlinear integral, which leads to a rigidly accu-rate method necessary to save computational resources compared to classical methods. The authors pro-pose a rigidly accurate method using an adapted scheme with a constant time step. For large systems, they use Newton's square root iteration in order to avoid explicit precomputation of the square root. The fourth paragraph gives the results of testing the method and the comparison with classical and mod-ern approaches for rigid systems. To determine the accuracy of specifying functionally specified objects, the depth buffer of the models (functional and polygonal) is calculated and points are compared to estimate the average difference in depth. Thus, the average deviation relative to the entire model is estimated. In conclu-sion, the authors briefly summarize the results and describe the approaches used in the work.

9. Algorithms for generating training sets in a system with case-based inference based on example situations [№4 за 2022 год]
Authors: Glukhikh I.N., Glukhikh D.I.
Visitors: 1229
The paper considers the issue of creating training sets and their scaling in machine learning problems. The subject of the study is the process of generating training sets based on examples in order to augment them. To implement the idea of expansion, it is proposed to use the transformation of existing examples of sit-uations. The transformation of examples is based on a well-known optimization method - the method of coordinate descent. The paper describes the statement of the problem of transformations of example situations in terms of the introduced representation model. There are proposed algorithms that make it possible to obtain an ex-tended set from the initial set of example situations specified using formal representations, which will include situations that meet the similarity criteria with these examples. The paper presents the testing of the proposed algorithms for expanding a set of example situations, car-ried out in order to form a data set for the studying artificial neural networks. The obtained results are of practical importance for training artificial neural networks used in intelligent decision support systems. The proposed algorithms make it possible to automate the formation of datasets using the available prepared and approved examples of typical situations and solving the transformation problem as the problem of finding the optimum of the similarity objective function.

10. Terms extraction from texts of scientific papers [№4 за 2022 год]
Authors: Dementeva Ya.Yu., E.P. Bruches , Batura T.V.
Visitors: 1808
The relevance of the task of extracting terms from the texts of scientific articles is due to the need for auto-matic annotation and extracting keywords in an ever-increasing flow of scientific and technical documents. This paper explores the influence of various language models on the quality of extracting scientific terms from Russian texts. We compare two models: the mBERT model that was pretrained on texts of different languages, and the ruBERT model pretrained only on Russian data. Two training sets of annotated texts were prepared. The au-thors carried out fine-tuning and further comparison of the performance indicators of the two models using these training sets. They also studied the influence of the choice of the language model on the quality of ex-tracting the terminology contained in the texts of scientific articles. The results have become the base for modernizing the algorithm for extracting terminology from texts applied by the Terminator tool, developed at the A.P. Ershov Institute of Informatics Systems. The obtained results showed that within the framework of the task of extracting terminology from the texts of Russian scientific articles, the ruBERT model, which gave the best performance in an ensemble with a dictionary and heuristics, can be considered as the most applicable model. In addition, the difference in the results of models on full and partial match can be stated due to the problem of defining the boundaries of terms in the texts described in the paper. The results obtained also allow concluding that the quality of the training set markup affects the quality of terminology extraction.

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