Wyniki wyszukiwania - Biblioteka Nauki

1

Protokoły transportowe w szybkich sieciach teleinformatycznych

100%

Chodorek R.

Telekomunikacja Cyfrowa : technologie i usługi

|

1998

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tom T. 1, z. 4

167-174

PL

Zmieniające się wymagania aplikacji oraz możliwość realizacji nowych usług w szybkich sieciach teleinformatycznych wymuszają zmiany w funkcjonowaniu usług transportowych. Do istotnych zmian możemy zaliczyć transmisję do wielu użytkowników (multicast) i realizację dostarczania danych w czasie rzeczywistym. W artykule zaprezentowano wprowadzane zmiany w realizacji usługi transportowej poprzez przedstawienie usług w klasycznych (TCP, UDP) jak i nowych (XTP, RMP, RMTP i RTP) protokołach transportowych.

EN

New application requirements and possibilities of high speed networks need changes in transport protocols. The most important is multicast transmission and real time data transfer. In the paper changes of transport service from classical protocol (TCP, UDP) to new one (XTP, RMP, RMTP, RTP) were presented.

2

Integrated teaching system

80%

Karpowicz S. , Sorko S. , Dainiak I.

Diagnostyka

|

2005

|

tom Vol. 33

259--262

PL

W artykule przedstawiona została problematyka wyższej oraz specjalistycznej edukacji w aspekcie wsparcia systemowego w postaci komputerowych baz danych. Autorzy stworzyli koncepcję budowy interaktywnego, multimedialnego systemu nauczania opartego na sieci komputerowej, jego główne aspekty i problemy, na których należałoby oprzeć taki system. Przedstawiono strukturę takiego systemu oraz przedstawiono sposoby realizacji tego projektu.

EN

The problems of higher, secondary and special education, linked to computer-based training aids are at issue. The building concept of the network interactive multimedia teaching system is introduced, the main aspects and principles, on which it is based, are mentioned. The structure of the system is described; the ways of realization are presented.

3

Systemy wspomagania decyzji doboru typu dostępu do sieci komputerowej w firmie

80%

Szewczyk A.

Business Informatics. Informatyka Ekonomiczna

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2014

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nr 1(31)

271-287

EN

A lot of companies have a problem with the selection of the type of computer network, because each of them has different characteristics and specifications. A businessman often does not know what he can expect from them and which type of network will allow him to fully exploit the potential of its business. The main objective of the work is to build a decision support system in this area. Intermediate target is to specify the characteristics or criteria which will be guided by a businessman in this selection. A comparative analysis of the type of access to the network using a case study was made in the work. The paper also developed the concept of a decision support system on the issue in question. As a result, six benchmarking criteria were specified and analyzed: security, data integrity, price, mobility, performance and configuration. As a result of the analysis, the final ranking was presented. Having used AHP method it showed which type of access to the network according to the given criteria provided by a businessman was the most suitable for him.

4

Ant algorithm for flow assignment in connection-oriented networks

80%

Walkowiak K.

International Journal of Applied Mathematics and Computer Science

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2005

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tom 15

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nr 2

205-220

EN

This work introduces ANB (bf Ant Algorithm for bf Non-bf Bifurcated Flows), a novel approach to capacitated static optimization of flows in connection-oriented computer networks. The problem considered arises naturally from several optimization problems that have recently received significant attention. The proposed ANB is an ant algorithm motivated by recent works on the application of the ant algorithm to solving various problems related to computer networks. However, few works concern the use of ant algorithms in the assignment of static flows in connection-oriented networks. We analyze the major characteristics of the ANB and try to explain its performance. We report results of many experiments over various networks.

5

Wykorzystanie programowych generatorów ruchu sieciowego w nauce i dydaktyce

80%

PASZKIEWICZ A.

Edukacja-Technika-Informatyka

|

2016

|

tom 7

|

nr 4

377-384

PL

W artykule zaprezentowano problematykę związaną z programowymi generatorami ruchu i ich wykorzystaniem w procesach dydaktycznych, jak również w obszarze prac badawczo-rozwojowych. Przedstawiono ich możliwości oraz ograniczenia funkcjonale w zakresie definiowanie ruchu sieciowego.

EN

The article presents issues related to programming traffic generators and their use in the processes of teaching and in the area of research and development as well. Their capabilities and functional limitations of network traffic definition are presented.

6

FPGA Implementation of Decision Trees and Tree Ensembles for Character Recognition in Vivado Hls

80%

Kułaga R. , Gorgoń M.

Image Processing & Communications

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2014

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tom Vol. 19, no. 2-3

71--82

EN

Decision trees and decision tree ensembles are popular machine learning methods, used for classification and regression. In this paper, an FPGA implementation of decision trees and tree ensembles for letter and digit recognition in Vivado High-Level Synthesis is presented. Two publicly available datasets were used at both training and testing stages. Different optimizations for tree code and tree node layout in memory are considered. Classification accuracy, throughput and resource usage for different training algorithms, tree depths and ensemble sizes are discussed. The correctness of the module’s operation was verified using C/RTL cosimulation and on a Zynq-7000 SoC device, using Xillybus IP core for data transfer between the processing system and the programmable logic.

7

Examination of robust D - stability of TCP - DCR protocol

80%

Klamka J. , Tańcula J.

Theoretical and Applied Informatics

|

2012

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tom Vol. 24, No. 4

327-344

EN

This paper presents non-linear mathematical model of a computer network with a part of wireless network. The article contains an analysis of the stability of the network based on TCP-DCR, which is a modification of the traditional TCP. Block diagram of the network model was converted to a form in order to investigate the D-stability using the method of the space of uncertain parameters. Robust D-stability is calculated for constant delays values.

PL

W pracy przedstawiono nieliniowy model matematyczny sieci komputerowej w postaci układu dwóch równań różniczkowych ze skupionym zmiennym w czasie opóźnieniem we współrzędnych stanu. Przedstawiono model w postaci schematu blokowego, a następnie dokonano przekształceń schematu zgodnie z linearyzacją równań. Wydajność aplikacji w dużym stopniu zależy od stosowanego w sieci algorytmu zarządzania kolejką. Aktywne zarządzanie kolejką (Active Queue Management) w rozpatrywanym modelu sieci komputerowej polega na zastosowaniu algorytmu RED (Random Early Detection) w sprzężeniu zwrotnym. Jeśli przyjąć, że sieć komputerowa jest specyficznym układem dynamicznym to możemy poddać badaniu stabilnści taki układ. Analityczne metody badania D-stabilności mogą być trudne do sprawdzenia, dlatego w niniejszej pracy zaproponowano metody graficzne znane z literatury. Przedstawiono również przykłady liczbowe badania stabilności dla rzeczywistej sieci komputerowej. Wykorzystano metodę częstotliwościową oraz metodę przestrzeni niepewnych parametrów quasi-wielomianów, która jest rozwinięciem klasycznej metody podziału D. Polega ona na wyznaczeniu w przestrzeni niepewnych parametrów quasi-wielomianów zbioru takich wartósci niepewnych parametrów, dla których jest on asymptotycznie stabilny. Przy użyciu tej metody określono granice obszaru odpornej D-stabilności. Wyznaczenie granic stabilności układu pozwoli zaprojektować sieć bezprzewodową bardziej wydajną, szybszą i odporną na błędy.

8

Performance of a router based on NetFPGA-1Gb/s cards

80%

Paszkiewicz A. , Więch P. , Gomółka Z.

Measurement Automation Monitoring

|

2015

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tom Vol. 61, No. 9

446--449

EN

Providing a flexible platform that also allows prototyping new network solutions opens new possibilities for designers, researchers and administrators. This solution are NetFPGA systems. Their additional advantage is the possibility of testing new networking protocols in a real heterogeneous environment. Until now, it has been mainly possible by using software tools such as, e.g. Opnet Modeler. Despite the very good mapping network environment in this type of solutions, it is necessary to carry out tests in the real network for their correct evaluation. The paper focuses on the analysis of the solution performance based on NetFPGA-1G cards as an alternative to the network nodes based on ASICs. Therefore a series of tests was carried out. They demonstrated the applicability of the platform in different layers of the network, e.g. access, aggregation, or core. Thus, the paper goal is to show the possibilities of using NetFPGA solutions in a network environment mainly of enterprise class.

9

Stress Testing MQTT Server for Private IOT Networks

80%

Hijazi G. , Hadi Habaebi M. , Al-Haddad A. , Zyoud A. M.

International Journal of Electronics and Telecommunications

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2021

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tom Vol. 67, No. 2

229--234

EN

The rapid development of the Internet of Things (IoT) and the wide area of application rise the IoT concept to be the future of the internet. Indeed, IoT environment has a special nature with a lot of constraints in term of resource consumption. Moreover, the data exchanged between things and the internet is big data. In order to achieve efficiency in IoT communication, many technologies and new protocols based on these technologies have been developed. This paper aims to study the performance of Message Queuing Telemetry Transport (MQTT) by implementing this protocol on test-bed network infrastructure and analyzing the performance properties such as delay, jitter, packet loss and throughput for real time and non-real time scenarios. Finally, future research issues in MQTT protocol are suggested.

10

Utilizing Modern Network Technologies in a Campus Network

80%

Goetzen P. , Makuch J. , Skowrońska-Kapusta A. , Marchlewska A. , Zachlod R.

Journal of Applied Computer Science Methods

|

2010

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tom Vol. 2 No. 2

171--189

EN

The purpose of this paper is to outline concepts and examples of reliable and ef-ficient communication systems for all parts involved in the modern education model. As proven in the presented paper, designing an academic-size network is a real challenge to a team of designers. The outcome vastly depends on the skill and experience of the design team.

11

Analysis of CHOKe - family active queue management

80%

Domański A. , Domańska J. , Klamka J.

Theoretical and Applied Informatics

|

2013

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tom Vol. 25, No. 1

49--66

EN

In the article we study a model of network transmissions with Active Queue Management in an intermediate IP router. We use the OMNET++ discrete event simulator to model the varies variants of the CHOKe algoithms. We model a system where CHOKe, xCHOKe and gCHOKe are the AQM policy. The obtained results shows the behaviour of these algorithms. The paper presents also the implementation of AQM mechanisms in the router based on Linux.

PL

W artykule został przedstawiony model sieciowej transmisji danych poprzez router z zaimplementowanymi mechanizmami Aktywnego Zarządzania Kolejką (AQM). Badania zachowania mechanizmów AQM zostały przeprowadzone przy użyciu symulatora zdarzeń dyskretnych OMNET++. Uzyskane wyniki zostały zweryfikowane w środowisku rzeczywistym. W oparciu o system operacyjny Linux stworzono programowy router implementujący mechanizmy wcześniej przebadane w środowisku symulacyjnym. Przeprowadzono analizę zachowania algorytmów AQM z rodziny CHOKe (CHOKe, xCHOKe, gCHOKe). W badaniach rozważano problem wpływu tych mechanizmów na tzw. agresywne (potrzebujące większego pasma) źródła transmisji danych.

12

Preventing Fraud Using Computer Networks

80%

Shapochka S.

Internal Security

|

2013

|

tom 5(2)

63-76

EN

In the article the author studies and analyzes the general theoretical writings of experts in the field of criminal law, criminology and criminal executive law related to the study of determinants of property crime, and information and statistics in the sphere of the global Internet and computer and telecommunication devices. A classification of computers as communication tools for the achievement of the information society in terms of its global contemporary possibilities is presented. Appropriateconclusions are drawn. The Council of Europe Convention on Cybercrime of 23 November 2001, the legislation of Ukraine, Russian Federation and United States are analyzed. The questions of prevention of fraud, perpetrated with the use of computer networks, the issues of cyber security were discussed. Concrete proposals on how to eliminate conditions conducive to the commission of cyber fraud are made and ways of effectively countering fraud committed through computer and telecommunications devices and computer networks are proposed. The prerequisites for the birth and development of the World Wide Web are studied, and the dynamics of the growth in the number of users in the world, Europe, Asia, USA, Ukraine are analyzed. Conclusions about the credibility of statistics on the number of active users of computer and telecommunication networks are drawn, the way they are counted, factors affecting data corruption, along with consideration for their most effective use. The reasons for passivity, lack of effectiveness of the security structures of the private sector in the fight against criminal encroachments using computer networks and technologies are identified.

13

Traffic control algorithms in computer networks. Part 2, Simulation researches of the algorithms

80%

Barczak A. , Sitkiewicz T.

Studia Informatica : systems and information technology

|

2009

|

tom Vol. 2(13)

5--19

EN

This article is the continuation of the first part entitled Review of algorithms. In the article presented were the author's simulator of a network and the tests performed with its help. In the first part the concept and functionality of the created simulator were described. The concept emerged on the basis of an analysis of existing solutions, as well as needs the created software has to fulfill. The second part of the article depicts the testing environment, i.e. network topology and simulation parameters used during the research. What is more, in the aforementioned part, provided was the comparison of the research run with the use of the author's software and its interpretation.

14

Implementation of remote control device using USB 1208LS

80%

KARAARSLAN, A. , ÖZER T.

Edukacja-Technika-Informatyka

|

2013

|

tom 4

|

nr 2

406-417

EN

In parallel with developments in technology, home automation systems are being increasingly used. In this study, computer networks and the power system can be controlled by Internet for a remote device. This application was carried out in two stages of software and hardware. The software is developed in C # programming language. This software is connected to the computer using a remote server devices, performed the required information has been sent. The second part of the application is prepared in the hardware. The information that come to the server Usb can handled and performed by Usb 1208LS. This circuit design performed and connected to the server Usb. After the coming data has been processed, target device which connected to the circuit making power control and commands sent to the device peaks and the application process has been completed the desired

15

Planowanie bezpiecznej komunikacji w sieciach komputerowych zgodnej z zaleceniami ITU-T

80%

Niemiec M. , Pach A. R. , Pacyna P.

Telekomunikacja Cyfrowa : technologie i usługi

|

2005

|

tom T. 7

21--28

PL

Niniejszy artykuł omawia problematykę projektowania architektury bezpieczeństwa dla komunikacji pomiędzy użytkownikami końcowymi w sieci komputerowej. Szczególną uwagę zwrócono na zgodność mechanizmów odpowiadających za ochronę danych z zaleceniami międzynarodowej organizacji normalizacyjnej ITU-T (International Telecommunication Union). Przedstawione zostały metody ochrony danych oraz techniki, za pomocą których realizowana jest bezpieczna komunikacja. Opisane zostały dwie przykładowe architektury bezpieczeństwa: jedna, powszechnie używana w środowiskach sieciowych, i druga, będąca własną propozycją autorów. Omawiając przedstawione rozwiązanie, zwrócono dużą uwagę na wydajność obu systemów.

EN

This paper introduces design considerations of a security architecture for network systems providing end-to-end communications. We present eight dimensions of a security architecture which is based on recommendations of International Telecommunication Union and a few security techniques that are often employed to protect against major security threats. We also present two examples of security architectures: the first of them is currently being deployed and exploited in production networks while the second is our own proposition.

16

Bezpieczne zasilanie średnich i dużych sieci komputerowych

80%

Piotrowski P.

Elektro Info

|

2007

|

tom nr 9

146-151

17

Flow caching effectiveness in packet forwarding applicati

80%

Czekaj M. , Jamro E.

Computer Science

|

2019

|

tom Vol. 20 (2)

145--163

EN

Routing algorithms are known to be potential bottlenecks for packet processing. Network ow caching can function as a general acceleration technique for packet processing workloads. The goal of this article is to evaluate the effectiveness of packet ow caching techniques in high-speed networks. The area of focus is the data distribution characteristics that lead to the effectiveness of caching network ows (connections). Based on a statistical analysis and simulations, the article sets the necessary conditions for the effective use of caches in packet forwarding applications. Public domain network traces were examined and measured for data locality. Software simulations show a strong correlation between the ow packet distance metrics and the cache hit rate.

18

Review of traffic control algorithms in computer networks

80%

Barczak A. , Sitkiewicz T.

Studia Informatica : systems and information technology

|

2008

|

tom Vol. 2(11)

15--26

EN

This paper presents comparison of popular traffic control algorithms in computer networks. It also contains descriptions of functioning of these algorithms. The first part of this paper contains description of evaluation criteria of traffic control algorithms (from system and user viewpoint). The second part of article contains description of new algorithms, which are theoretically improved or brand new, just introduced for practical use. These algorithms are developmental and eliminate disadvantages of already existing algorithms. The third part of this paper contains description of classical algorithms, which are well known, described and researched. It contains also propositions of modifications of classical linear programming algorithms. These modifications are for adjusting these algorithms to described problem.

19

Measurement Data Acquisition System Utilising the GSM Phone System

80%

Brocki J. , Goetzen P. , Makuch J. , Marchlewska A. , Skowrońska-Kapusta A.

Journal of Applied Computer Science Methods

|

2010

|

tom Vol. 2 No. 2

201--211

EN

We present a new approach to designing of application which can be used for data acquisition. Cellular phone is used to transfer the data. Connecting many phones builds highly scalable measurement network. SMS messages were used to transfer the data.

20

Charakter ruchu HTTP w lokalnych sieciach bezprzewodowych

80%

Olejnik R.

Metody Informatyki Stosowanej

|

2011

|

tom nr 4

175-180

EN

The article presents research on the nature of the traffic in wireless local area networks (WLAN). There are presented conditions for assuming the traffic as self-similar. Then undertaken experiments are shown — for the traffic collected in five WLANs, three methods has been used: IDC (index of dispersion) and CV (coefficient of variation) indices, R=S method and method of variance time analysis. The article ends with final conclusions regarding observed dependence.