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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
441

QoS v IP síti / QoS in IP network

Bumbál, Miroslav January 2009 (has links)
Master 's thesis deals about computer networks, which constitutes a global communication structure and play a very important role in today's society. The rapid development of Internet, the emergence of new multimedia applications and their increasing use of calls to the efficient functioning of the creation of such governance mechanisms of transmission, which are able to secure the required parameters. The thesis deals about the issue of quality of service (QoS) in IP networks. It presents the basic characteristics and requirements of these networks for the transmission of sensitive data by the quality of services, deals with the QoS definition, and describes the essential parameters to be followed to achieve the required quality of service in practical deployment. In addition, lists the various principles and options to ensure QoS in computer networks. Generally, it represents the Cisco 1841 router features and options to ensure quality of service in the network based on these routers. Practical thesis part provides two types of model IP networks, which were designed in order to verify the impact of service quality in real practice. Of the known methods to ensure QoS, which include a mechanism of Integrated services, Differentiated services, it focus its content about the Differentiated Services and the implementation of these in proposed network model. The last part of the work presents the results obtained by the impact of quality of service for the applications and their assessment.
442

Samoorganizující se sítě typu MESH / Self-organizing MESH wireless networks

Němec, Petr January 2009 (has links)
This master thesis deals with self organized Mesh network. It describes routing and particular routing protocols, which are used in these networks. The thesis deals with Mesh network QoS assurance. Analysis and theoretical background of Mesh networks, routing and router protocols are included in the first chapter. Basic models of assuring Quality of Service are also described. Those are Best Effort, IntServ and DiffServ. Second chapter describes the devices used in the specific Mesh network topology - Trospos 5210 MetroMesh router produced by Motorola Canopy. Basic settings and properties required to establish a Mesh network are described. Next part of the thesis is the design implementation, which involves creation and configuration of the Mesh Network. Network configuration consisting of two Gateway points and afterwards behaviors of the network in a steady state versus one gate failure are compared. Furthermore, implementation of QoS according to components that support two types of QoS assurance regarding type of bandwidth reservation and defined traffic classes. In conclusion, the thesis describes measurement methods of QoS parameters for chosen applications, evaluation and comparison of measurement results for both types of Quality of Service assurance.
443

Implementace kvality služby v bezdrátových sítích / Implementation of Quality of Service into Wireless Networks

Kaman, Štěpán January 2009 (has links)
Wireless networks are currently the frequent access connection to the local network or the Internet. Until 2005 there was no support in the 802.11 standard priority data and the use of multimedia services in these networks is problematic. Thesis deals with the standard IEEE 802.11 standard and quality of service support including IEEE 802.11e. They discussed methods of access to transmission medium, differences in the MAC sublayer, the reader issues in the transmission of priority data and the requirements for these data. In Opnet Modeler was created wireless network with access points and stations on which they are carried out simulations at different strain of transmitted data. It studied the difference in the use of DCF and EDCF method, used in the network with QoS support. In particular, it examined the behavior of priority voice and video data in both networks. The focus is on key parameters such as throughput, dropping data, packet loss, delay, jitter and the size of broadcasting front. The measured data are analyzed, and differences in the network without the support and promoting the quality of services are compared and evaluated. Part of this work is the role of laboratory in the Opnet Modeler.
444

Hotspotový systém pro více operátorů / Hotspot system for more network operators

Strmiska, Roman January 2009 (has links)
Master’s thesis deals with the design and realization of a hotspot system for more Operators, it solves problems of QoS, billing of transferred data and distribution of services via a common wireless interface. The theoretic part is oriented to the selection of a suitable technology and explanation of a legislation, which relates to an activity of the hotspot‘s network. The practical part solves the choice of hardware, design and realization of the experimental network. In conclusion are tested transit parameters of the network and its functionality.
445

Simulace bezdrátových a mobilních UMTS sítí s použitím QoS / Wireless and mobile UMTS networks simulation using QoS

Zapletal, Lukáš January 2010 (has links)
Diplomová práce je psána v angličtině a věnuje se standardu IEEE 802.11e, obsahujícím podporu kvality služeb a taky pojednává o kvalitě služeb QoS (Quality of Service) v systému UMTS. Rozebrány jsou hlavní teoretické pilíře daných mechanizmů a praktická část se zabývá simulacemi síťových modelů. Standard 802.11e objasňuje propojení vrstev na fyzické úrovni a zmiňuje metody přístupu k přenosovému médiu DCF, PCF, HCF, EDCA, HCCA. Dále přístupové kategorie a také odlišnosti v MAC podvrstvě, je rozebrána problematika při přenosu prioritních dat na základě identifikátorů. Vzpomenuta je taky struktura formátu rámce a techniky s rozprostřeným spektrem. Časové limity pro doručení prioritních dat a požadavky kladené na tyto data je možné snadno srovnat v tabulkách. Problematika kvality služeb je velice komplexní záležitost, nicméně jsou rozebrány základní klíčové parametry jako koncové zpoždění, jitter, zahazování dat, propustnost, velikost front a hodnota MOS. Zmíněny jsou i mechanizmy integrovaných RSVP a diferencovaných služeb pro zajištění QoS. U systému třetí generace UMTS je objasněna architektura a společná kooperace se systémem GSM. Vzájemné propojení obou sítí je zřejmé z obrázků. Zvýšený zájem je věnován vrstvovému modelu a funkcím RRM pro zajištění QoS. Objasněny jsou různé druhy předávání hovorů, tzv. Handover Control a funkce Admission Control. Rozebrány jsou jednotlivé třídy provozu Conversational, Streaming, Interactive a Background. Praktická část se odehrává v simulačním prostředí programu OPNET Modeler. Byly vytvořeny dva modely s různými scénáři pro srovnání zajištění QoS. Model objasňující princip standardu IEEE 802.11e obsahuje dvě bezdrátové sítě s přístupovými body a stanicemi, na kterých jsou sledovány simulace s různým zatížením přenášených dat. Pro porovnání výsledků je zkoumán rozdíl při použití metody HCF v síti s podporou QoS. Model UMTS sítě obsahuje základnové stanice Node B s možností vysílání do tří sektorů. Mobilní účastník pohybující se po trajektorii představuje princip funkce Softer Handover. Konfrontace mezi scénáři je zastoupena kompresí záhlaví pomocí funkce PDCP a rozlišení Type of Service. Obzvláště je sledováno chování prioritních dat hlasu a videa u obou sítí. Naměřená data zastupují grafy a průběhy výsledních charakteristik. Analýza diskutuje odlišnosti u sítě bez podpory a s podporou kvality služeb. Rozdíly jsou porovnány a vyhodnoceny dle metodiky QoS. Součástí práce je i řešení problémů při návrhu UMTS sítě a podány jsou taky užitečné tipy a návrhy na jejich odstranění. Projekty v simulačním softwaru jsou popsány dle postupu vyhotovení, avšak hloubka podrobností je potlačena. Detaily nejsou rozebírány, protože se očekává pokročilá znalost mechanizmů a jistá dávka zkušeností s programem.
446

Optimalizace přístupových sítí pro multimediální služby / Optimization of access networks for multimedia services

Slavíček, Tomáš January 2010 (has links)
This thesis describes the problems of access networks and their existing types. It discusses the important parameters for multimedia services. It considers the possibility of using various networks at the localities. It presents modern multimedia services and their requirements for access networks. Next step describes the possible use of QoS to optimize access networks used for multimedia services. Multimedia services to different types of networks and limits which these types of networks have, are simulated in the program Opnet Modeler. Measurements of values important for securing quality of services are implemented at selected real access networks. In conclusion, the results of simulations and measurements are subjected to comparative analysis.
447

Analýza přenosu dat v konvergované síti / Analysis of data transport in converged network

Menšík, David January 2011 (has links)
This thesis deals with data transmission applications in the converged network, focusing on the WiFi network IEEE 802.11. The theoretical part describes the cause and nature of converged networks. One chapter is devoted to a description of IEEE 802.11, which is next to different standards and options described architecture, coordination and access network QoS solution to that standard. The research is based on custom design converged networks, and WiFi elements in the environment of graphic simulation software OPNET Modeler. In the proposed network was also simulated the operation of services such as voice, video conferencing, FTP and HTTP streaming. Results of simulation data traffic in the network are then analyzed. At the Conclusion of the thesis, is in OPNET Modeller program created the role of laboratory. The essence here is the comparison of operating a converged network, with and without quality support services.
448

Realizace QoS filtrace na IPv6 protokolu s využitím Linuxu / Establishment of QoS filtering on IPv6 protocol using Linux

Matušina, František January 2011 (has links)
This diploma thesis is interested in establishment of QoS filtering on IPv6 protocol usány Linux. Thesis describe protocol IPv4 and protocol IPv6 and their differences. Problematic is implement to Linux. Because this problem is implement in Linux, I describe a few distribution of Linux in thesis. Another part of thesis are about QoS and about QoS implement on TCP/IP model. In practise part is make a propsal resolution working site under protocol IPv6 in Linux. Realize include install of server, clients and their configuration. Realize include script, that account, take control of the traffic. Changeing traffic is show in graphs. Graphs of measure are comented and outcome clear up. All graphs and scripts are add to attachments.
449

Možnosti využití neuronových sítí v síťových prvcích / Potential application of neural networks in network elements

Babnič, Patrik January 2011 (has links)
The goal was to get acquainted with the problems of network elements to describe neural networks that can be used to manage such a feature. The theoretical part deals with the neural networks from their inception to the present. It focuses mainly on the network, witch can be used for management control. These are the two network: Hopfield network and Kohonen network. The practical part deals with the network element model and ist implementation. It contains a practical element model using a neural network, witch is controlled by a network element.
450

Podpora QoS v MANET sítích / Support of QoS in MANET networks

Figurny, Roman January 2012 (has links)
The theoretical part of Master's thesis has been dealing with issues of MANET networks, issues of providing quality of services in MANET networks and analysis of various implementations of quality of services in these networks. At the start of the practical part of this thesis was described modified OLSR process model with support of quality of services. In simulation program OPNET Modeler was designed a topology of MANET network, firstly was run a simulation of this network without any support of quality of services and then was run a simulation with support of quality of services. The results of these simulations were analyzed, compared and graphically interpreted. In the next part of this thesis was designed a real MANET network with OLSR support. OLSR network communication was captured with the use of Wireshark. In the last part of this thesis was firstly described a meaning and functions of plugins in OLSR implementation and then was developed a plugin which is responsible for sending messages which contain a state of the links between nodes of MANET networks.

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