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Android application for measuring user satisfaction with mobile data service
Kunc, Jaroslav ; Povoda, Lukáš (referee) ; Červenák, Rastislav (advisor)
The bachelor thesis focuses on user satisfaction with mobile data services. The thesis in this context explains the terms of Quality of Service, Quality of Experience and Crowdsourcing. An another part of a thesis is focusing on describing the development of applications for the Android platform, including the distribution and application testing. In the practical part of thesis, the application for the Android platform is created and it is predicting the user satisfaction with mobile data services on the basis of an analytical model for calculating MOS (Mean Opinion Score).
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Wireless and mobile UMTS networks simulation using QoS
Zapletal, Lukáš ; Vychodil, Petr (referee) ; Vymazal, Michal (advisor)
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.
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Optimization of access networks for multimedia services
Slavíček, Tomáš ; Reichert, Pavel (referee) ; Šporik, Jan (advisor)
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.
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QoS optimization and modern communication services delay analysis
Novák, Přemek ; Škorpil, Vladislav (referee) ; Endrle, Pavel (advisor)
This thesis consists of theoretical and practical parts. The theoretical part contains an analysis of the problems of wireless networkssolutions individual standards and methodologies to ensure quality of service. In the practical part using the OPNET Modeler, a number of different simulation models and their evaluation. It is a model of individual standards, support mobility and interference effects on quality of service.
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Multimedia transmissions in wireless networks
Zicha, Karel ; Šedý, Jakub (referee) ; Krkoš, Radko (advisor)
The aim of the thesis is to summarize the qualities of wireless networks operating in the frequency band of 2.4 GHz. In the first part, theoretical knowledge about the architecture of the networks and the comparison of individual standards are presented; the types of interference caused by external devices, including the issue of a hidden node. The possibilities of providing quality services are described following the qWave set. Further, we explore individual access methods and multimedia protocols. The second part comprises the practical verification of this knowledge. The throughput tests of the individual networks were conducted regarding the type of the issue. In the conclusion, the recorded knowledge is described and evaluated.
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Simulation of Data Transmissions in Integrated Networks
Rozsypal, Pavel ; Endrle, Pavel (referee) ; Škorpil, Vladislav (advisor)
The goal of this assignment was to analyze the issue of data transfer in integrated networks focusing on quality of service. The thesis describes the various network elements, their function, advantages and disadvantages. Attention was also paid to neural networks, with a focus on the analogy between biological neuron and the artificial neuron. Another part of paper was dedicated to the simulation possibilities of these network in MATLAB. To simulate the behavior of network elements was used OPNET IT Guru software.
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Quality of service support in unix-like operating system for communication in WiFi networks
Mizera, Josef ; Komosný, Dan (referee) ; Novotný, Vít (advisor)
Diploma thesis is focused on the supporting of Quality of Services in wireless networks, especially in the Linux operation systems. The topic is connected not only with OS, but also with the wireless standard, which supports QoS in wireless networks called IEEE 802.11e. QoS is needed especially for time-consuming data transfers in real time. The theoretical part deals with the theoretical analysis of the issue of the QoS support. There are described parameters, which occurred in quality of services support. This section also deals with the division of services that are used to transmit data across computer networks. It also describes the QoS support in wireless networks according 802.11e, its implementation and methods of accessing a medium with a without possibility of traffic. This part is followed by a description of QoS support in UNIX operating systems. The chapter describes how is the QoS support designed in these operating systems. There are also characterized concrete tools which are used for control the data flow in the operating systems using Linux. At the end the theoretical part deals with different types of queues and methods used in linux OS. In the practical part of the thesis, there are various designed topologies and scenarios to verify the functionality of QoS support in wireless networks using a Unix system. These chapters show the results of different tests at selected transmission data streams that are sensitive to transmission time. There is also verified cooperation of QoS support between devices operating on the network and data link layers. The output of this work is to design a laboratory exercise for the subject Network Architecture. This exercise is focused on familiarization with the QoS support functionality in wireless networks and in Unix-like operating systems. This chapter also describes the devices and programs that are needed to measure this task. The last part of the chapter describes the procedure for the preparation of the measuring station. For this laboratory task, there is an inserted manual in the annex.
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MultiProtocol Label Switching technology in Ethernet networks
Kiška, Martin ; Vlček, Lukáš (referee) ; Novotný, Vít (advisor)
In the introduction of this thesis the reasons for transition from older to a new technology called MultiProtocol Label Switching are mentioned – the modern technology enables simple network extension. The theoretical part contains basic principles of this techno- logy and their practical application for supplying private networks to the customers using provider’s network. In practical part packets are analyzed considering the theory. In addi- tion. All the technologies tested on a real network. Experience gained while working on this thesis are assessed during creating laboratory task for class Architecture of Networks intended for students of Bachelor’s study programme.
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Quality of services in IP Telephony in Wirelass Networks
Slavíček, Tomáš ; Kyselák, Martin (referee) ; Vyoral, Josef (advisor)
The thesis deals with the principles of assurance quality of services in IP networks. The first part of the thesis describes specifications which are required by current applications for data network, and also illustrates the methods suitable for solving those requirements. The most attention is given to multimedia service VoIP whose development has not been finished from far. That theoretical knowledge implies in the second part of the thesis which analyzes the implementation of assurance QoS for the service VoIP within the standard 802.11, or more precisely, for wireless networks in general. The simulation of wireless networks within the program Opnet Modeler and the attest of the ability to assure QoS within both wireless networks and their limitations with an unswitched network are described in the next step. The current possibilities how to build up WLAN with the bearing QoS are sized up in conclusion.
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