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1
Energooszczędne centrum przetwarzania danych
Niewiadomska-Szynkiewicz E., Arabas P.
Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne
|
2018
|
nr 8-9
609--614, CD
PL
Wzrostowi zapotrzebowania na moc obliczeniową oraz natężenie ruchu w sieci IP nie towarzyszy obecnie pojawianie się technologii chroniących operatorów i środowisko naturalne przed analogicznym wzrostem zapotrzebowania na energię w sektorze. Artykuł 1 przedstawia wyniki badań, których celem jest opracowanie koncepcji i realizacja systemu komputerowego do energooszczędnego sterowania obciążeniem rozproszonego centrum przetwarzania danych oraz szybkością pracy jednostek obliczeniowych i urządzeń sieciowych przekazujących komunikaty z danymi. Niniejsza praca prezentuje propozycję dwupoziomowej struktury zarządzania przydziałem bloków zadań do klastrów, a następnie do poszczególnych serwerów obliczeniowych. Decyzje o alokacji zadań są podejmowane w wyniku rozwiązania zadania minimalizacji zużycia zasobów energetycznych systemu, przy założeniu zagwarantowania wymaganego poziomu jakości usług.
EN
The proposition of a framework for energy-aware control in a large scale HPC (High Performance Computing) system is presented and discussed. The implementation consists of a global computing resource manager that is implemented in the central control level, energy-efficient backbone network connecting computing clusters and data centers and a local resource manager implemented in each cluster. The decisions about activity and power status of computer and network equipment are determined by solving the problem of minimizing the energy used by the whole HPC system. A simulation-based optimization scheme is utilized to calculate optimal allocation of a set of tasks to clusters.
2
Content available Heavy Gas Cloud Boundary Estimation and Tracking using Mobile Sensors
Krzysztoń M., Niewiadomska-Szynkiewicz E.
Journal of Telecommunications and Information Technology
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2016
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nr 3
38--49
EN
This paper addresses issues concerned with design and managing of monitoring systems comprised of mobile wireless sensing devices (MANETs). The authors focus on self-organizing, cooperative and coherent networks that maintain a continuous communication with a central operator and adopt to changes in an unknown environment to achieve a given goal. The attention is focused on the development of MANET for heavy gas clouds detection and its boundary estimating and tracking. Two strategies for constructing the MANET are described, in which sensors explore the region of interest to detect the gas cloud, create temporary network topology and finally, cover the cloud boundary, and track the moving cloud. The utility and efficiency of the proposed strategies has been justified through simulation experiments.
3
Content available Energy-saving Algorithms for the Control of Backbone Networks: A Survey
Kamola M., Niewiadomska-Szynkiewicz E., Arabas P., Sikora A.
Journal of Telecommunications and Information Technology
|
2016
|
nr 2
13--20
EN
The rapid growth of energy demand by wired IP networks can be mitigated on hardware and software levels. While upgrading to more efficient transmission media still brings biggest savings, we take a look here at power-saving algorithms that combine the capability of setting networking equipment in arbitrary energy states which, combined with profound knowledge of the network traffic matrix, leads to considerable complex optimization problem formulations. Alternatively, lightweighted heuristic approaches are presented, built on much simpler network model but still capable to perform energy-efficient traffic engineering.
4
Content available Comparative Study of Supervised Learning Methods for Malware Analysis
Kruczkowski M., Niewiadomska-Szynkiewicz E.
Journal of Telecommunications and Information Technology
|
2014
|
nr 4
24--33
EN
Malware is a software designed to disrupt or even damage computer system or do other unwanted actions. Nowadays, malware is a common threat of the World Wide Web. Anti-malware protection and intrusion detection can be significantly supported by a comprehensive and extensive analysis of data on the Web. The aim of such analysis is a classification of the collected data into two sets, i.e., normal and malicious data. In this paper the authors investigate the use of three supervised learning methods for data mining to support the malware detection. The results of applications of Support Vector Machine, Naive Bayes and k-Nearest Neighbors techniques to classification of the data taken from devices located in many units, organizations and monitoring systems serviced by CERT Poland are described. The performance of all methods is compared and discussed. The results of performed experiments show that the supervised learning algorithms method can be successfully used to computer data analysis, and can support computer emergency response teams in threats detection.
5
Econet - energooszczędne techniki dla przewodowych sieci komputerowych
Kamola M., Arabas P., Wiśniewski T., Niewiadomska-Szynkiewicz E., Malinowski K., Karpowicz M., Sikora A., Marks M., Mincer M.
Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne
|
2012
|
nr 8-9
650-655
PL
Przedstawiono projekt Econet, opracowujący mechanizmy skoordynowanego oszczędzania energii na wszystkich poziomach funkcjonalnych i we wszystkich obszarach topologicznych sieci. Prace, wykonywane w projekcie przez NASK oraz Instytut Automatyki i Informatyki Stosowanej PW, skupiają się na stworzeniu struktury i algorytmów sterowania siecią. Dokonano analizy zużycia energii we współczesnym sprzede, opisano projekt interfejsu dla energooszczędnych urządzeń, zadania optymalizacji energii w obszarze sieci oraz narzędzia symulacyjnej weryfikacji konstruowanych algorytmów.
EN
Econet, whose goal is to develop energy-efficient network hardware and control logic, is presented. The main contribution of Research and Academic Computer Network and of Inst. of Computation and Control Engineering to the project consists in creation of a network control structure and algorithms. Power consumption analysis for contemporary devices, API design for green networking components, energy optimization problem formulation and tools for verification through simulation, arę presented as the current main project achievements by the authors.
6
Content available Application of Social Network Analysis to the Investigation of Interpersonal Connections
Mincer M., Niewiadomska-Szynkiewicz E.
Journal of Telecommunications and Information Technology
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2012
|
nr 2
83-91
EN
Social network analysis (SNA) is an important and valuable tool for knowledge extraction from massive and unstructured data. Social network provides a powerful abstraction of the structure and dynamics of diverse kinds of interpersonal connection and interaction. In this paper, we address issues associated with the application of SNA to the investigation and analysis of social relationships of people. We provide a brief introduction to representation and analysis of social networks, SNA models and methods. The main objective is to investigate the application of SNA techniques to data mining in case of two social networks Facebook and Twitter. The presented simulations illustrate how social analysis can be used to determine the interpersonal connections, importance of actors in a given social network and detect communities of people. We then discuss strength and weakness of SNA techniques.
7
Content available A Survey of Energy Efficient Security Architectures and Protocols for Wireless Sensor Networks
Daniluk K., Niewiadomska-Szynkiewicz E.
Journal of Telecommunications and Information Technology
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2012
|
nr 3
64-72
EN
Data security and energy aware communication are key aspects in design of modern ad hoc networks. In this paper we investigate issues associated with the development of secure IEEE 802.15.4 based wireless sensor networks (WSNs) - a special type of ad hoc networks. We focus on energy aware security architectures and protocols for use in WSNs. To give the motivation behind energy efficient secure networks, first, the security requirements of wireless sensor networks are presented and the relationships between network security and network lifetime limited by often insufficient resources of network nodes are explained. Second, a short literature survey of energy aware security solutions for use in WSNs is presented.
8
Content available A Hybrid CPU/GPU Cluster for Encryption and Decryption of Large Amounts of Data
Niewiadomska-Szynkiewicz E., Marks M., Jantura J., Podbielski M.
Journal of Telecommunications and Information Technology
|
2012
|
nr 3
32-39
EN
The main advantage of a distributed computing system over standalone computer is an ability to share the workload between cores, processors and computers. In our paper we present a hybrid cluster system - a novel computing architecture with multi-core CPUs working together with many-core GPUs. It integrates two types of CPU, i.e., Intel and AMD processor with advanced graphics processing units, adequately, Nvidia Tesla and AMD FirePro (formerly ATI). Our CPU/GPU cluster is dedicated to perform massive parallel computations which is a common approach in cryptanalysis and cryptography. The efficiency of parallel implementations of selected data encryption and decryption algorithms are presented to illustrate the performance of our system.
9
Content available Localization in wireless sensor networks: classification and evaluation of techniques
Niewiadomska-Szynkiewicz E.
International Journal of Applied Mathematics and Computer Science
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2012
|
Vol. 22, no. 2
281-297
EN
Recent advances in technology have enabled the development of low cost, low power and multi functional wireless sensing devices. These devices are networked through setting up a Wireless Sensor Network (WSN). Sensors that form a WSN are expected to be remotely deployed in large numbers and to self-organize to perform distributed sensing and acting tasks. WSNs are growing rapidly in both size and complexity, and it is becoming increasingly difficult to develop and investigate such large and complex systems. In this paper we provide a brief introduction to WSN applications, i.e., properties, limitations and basic issues related to WSN design and development. We focus on an important aspect of the design: accurate localization of devices that form the network. The paper presents an overview of localization strategies and attempts to classify different techniques. A set of properties by which localization systems are evaluated are examined. We then describe a number of existing localization systems, and discuss the results of performance evaluation of some of them through simulation and experiments using a testbed implementation.
10
Content available Heterogeneous GPU&CPU cluster for High Performance Computing in cryptography
Marks M., Jantura J., Niewiadomska-Szynkiewicz E., Strzelczyk P., Góźdź K.
Computer Science
|
2012
|
Vol. 13 (2)
63-79
EN
This paper addresses issues associated with distributed computing systems and the application of mixed GPU&CPU technology to data encryption and decryption algorithms. We describe a heterogenous cluster HGCC formed by two types of nodes: Intel processor with NVIDIA graphics processing unit and AMD processor with AMD graphics processing unit (formerly ATI), and a novel software framework that hides the heterogeneity of our cluster and provides tools for solving complex scientific and engineering problems. Finally, we present the results of numerical experiments. The considered case study is concerned with parallel implementations of selected cryptanalysis algorithms. The main goal of the paper is to show the wide applicability of the GPU&CPU technology to large scale computation and data processing.
11
Content available The IP QoS System
Burakowski W., Śliwiński J., Tarasiuk H., Bęben A., Niewiadomska-Szynkiewicz E., Pyda P., Mongay Batalla J.
Journal of Telecommunications and Information Technology
|
2011
|
nr 3
5-11
EN
This paper shortly describes the IP QoS System which offers strict quality of service (QoS) guarantees in IP-based networks and supports a number of, so called, classes of services. Such solution requires to implement in the network a set of QoS mechanisms and algorithm working on packet, connection request and provisioning levels. Furthermore, we require signaling system for informing the network about new connection request and network resource allocation capabilities for providing required resources to given connection. The IP QoS System is based on the next generation networks (NGN) and differentiated services (DiffServ) architectures and, at least for now, it is designed for single domain only.
12
Content available Localization in Wireless Sensor Networks Using Heuristic Optimization Techniques
Niewiadomska-Szynkiewicz E., Marks M., Kamola M.
Journal of Telecommunications and Information Technology
|
2011
|
nr 4
55-64
EN
Many applications of wireless sensor networks (WSN) require information about the geographic location of each sensor node. Devices that form WSN are expected to be remotely deployed in large numbers in a sensing field, and to self-organize to perform sensing and acting task. The goal of localization is to assign geographic coordinates to each device with unknown position in the deployment area. Recently, the popular strategy is to apply optimization algorithms to solve the localization problem. In this paper, we address issues associated with the application of heuristic techniques to accurate localization of nodes in a WSN system. We survey and discuss the location systems based on simulated annealing, genetic algorithms and evolutionary strategies. Finally, we describe and evaluate our methods that combine trilateration and heuristic optimization.
13
Content available A Software Platform for Research on Auction Mechanisms
Kamola M., Niewiadomska-Szynkiewicz E., Malinowski K., Stańczuk W., Pałka P.
Journal of Telecommunications and Information Technology
|
2011
|
nr 3
38-46
EN
The platform for research on auction mechanisms is a distributed simulation framework providing means to carry out research on resource allocation efficiency mechanisms and user strategies. Both kinds of algorithms examined are completely user-defined. Interaction of algorithms is recorded and pre-defined measures for the final resource allocation are calculated. Underlying database design provides for efficient results lookup and comparison across different experiments, thus enabling research groupwork. A recognised, open and flexible information model is employed for experiment descriptions.
14
Content available Price Method and Network Congestion Control
Malinowski K., Niewiadomska-Szynkiewicz E., Jaskóła P.
Journal of Telecommunications and Information Technology
|
2010
|
nr 2
73-77
EN
Price instruments are useful in achieving market balance conditions in various markets. Those instruments can be also used for control of other composite systems. The formulation and basic properties of the Price Method are reviewed and then the congestion control by price instruments in a computer network is described and tested.
15
Content available A Software Platform for Global Optimization
Niewiadomska-Szynkiewicz E., Marks M.
Journal of Telecommunications and Information Technology
|
2010
|
nr 3
49-56
EN
This paper addresses issues associated with the global optimization algorithms, which are methods to find optimal solutions for given problems. It focuses on an integrated software environment - global optimization object-oriented library (GOOL), which provides the graphical user interface together with the library of solvers for convex and nonconvex, unconstrained and constrained problems. We describe the design, performance and possible applications of the GOOL system. The practical example - price management problem - is provided to illustrate the effectiveness and range of applications of our software tool.
16
Comparative Study of Single System Image Clusters
Osiński P., Niewiadomska-Szynkiewicz E.
Prace Naukowe Politechniki Warszawskiej. Elektronika
|
2009
|
z. 169
145-154
EN
Cluster computing has been identified as an important new technology that may he used to solve complex scientific and engineering problems as well as to tackle many projects in commerce and industry. In this paper we present an overview of three Linux-based SSI cluster systems. We compare their stability, performance and efficiency.
17
Content available Parallel and Distributed Simulation of Ad Hoc Networks
Sikora A., Niewiadomska-Szynkiewicz E.
Journal of Telecommunications and Information Technology
|
2009
|
nr 3
76-84
EN
Modeling and simulation are traditional methods used to evaluate wireless network design. This paper addresses issues associated with the application of parallel discrete event simulation to mobile ad hoc networks design and analysis. The basic characteristics and major issues pertaining to ad hoc networks modeling and simulation are introduced. The focus is on wireless transmission and mobility models. Particular attention is paid to the MobASim system, a Javabased software environment for parallel and distributed simulation of mobile ad hoc networks. We describe the design, performance and possible applications of presented simulation software.
18
Content available Multiobjective Approach to Localization in Wireless Sensor Networks
Marks M., Niewiadomska-Szynkiewicz E.
Journal of Telecommunications and Information Technology
|
2009
|
nr 3
59-67
EN
Wireless sensor network localization is a complex problem that can be solved using different types of methods and algorithms. Nowadays, it is a popular research topic. What becomes obvious is that there are several criteria which are essential when we consider wireless sensor networks. Our objective is to determine accurate estimates of nodes location under the constraints for hardware cost, energy consumption and computation capabilities. In this paper the application of stochastic optimization for performing localization of nodes is discussed. We describe two phase scheme that uses a combination of the trilateration method, along with the simulated annealing optimization algorithm. We investigate two variants of our technique, i.e., centralized and distributed. The attention is paid to the convergence of our algorithm for different network topologies and trade-off between its efficiency and localization accuracy.
19
Content available Comparative Study of Wireless Sensor Networks Energy-Efficient Topologies and Power Save Protocols
Niewiadomska-Szynkiewicz E., Kwaśniewski P., Windyga I.
Journal of Telecommunications and Information Technology
|
2009
|
nr 3
68-75
EN
Ad hoc networks are the ultimate technology in wireless communication that allow network nodes to communicate without the need for a fixed infrastructure. The paper addresses issues associated with control of data transmission in wireless sensor networks (WSN) - a popular type of ad hoc networks with stationary nodes. Since the WSN nodes are typically battery equipped, the primary design goal is to optimize the amount of energy used for transmission. The energy conservation techniques and algorithms for computing the optimal transmitting ranges in order to generate a network with desired properties while reducing sensors energy consumption are discussed and compared through simulations. We describe a new clustering based approach that utilizes the periodical coordination to reduce the overall energy usage by the network.
20
Content available remote Optimization schemes for wireless sensor network localization
Niewiadomska-Szynkiewicz E., Marks M.
International Journal of Applied Mathematics and Computer Science
|
2009
|
Vol. 19, no 2
291-302
EN
Many applications of wireless sensor networks (WSN) require information about the geographical location of each sensor node. Self-organization and localization capabilities are one of the most important requirements in sensor networks. This paper provides an overview of centralized distance-based algorithms for estimating the positions of nodes in a sensor network. We discuss and compare three approaches: semidefinite programming, simulated annealing and two-phase stochastic optimization-a hybrid scheme that we have proposed. We analyze the properties of all listed methods and report the results of numerical tests. Particular attention is paid to our technique-the two-phase method-that uses a combination of trilateration, and stochastic optimization for performing sensor localization. We describe its performance in the case of centralized and distributed implementations.
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