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Quality of Service Ensurence in Data-Networks
Mareček, Petr ; Komosný, Dan (referee) ; Koton, Jaroslav (advisor)
The thesis deals with the issue of ensuring the Quality of Service (QoS) in data networks. The first part is theoretical, where is described QoS technology and her mechanisms. At the end of the theoretical part, possible queuing systems are shortly presented. The second part of the thesis deals with the design and implementation of a laboratory exercise with the aim of proving theoretical knowledge and evaluating the suitability of a certain queuing system according to the provided services.
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Evaluation of influence of UMTS radio access network parameters on network performance using Opnet Modeler simulation environment
Konečný, Zbyněk ; Škorpil, Vladislav (referee) ; Novotný, Vít (advisor)
This bachelor thesis deals with testing the effect of various parameters and their subsequent influence on the operation of the entire UMTS access network. Each simulation will be implemented in Opnet Modeler, which is used for network testing based on packet switching. The aim of this work is the most effective operation of UMTS networks. Since the UMTS network uses a shared radio environment for all users close to one transmitter, the total capacity of one cell is dependent on the size of interference produced by mobile terminals in the cell. Increasing the capacity of cells can be done by properly elected handover. The first part of this work will therefore concern different types of handovers and their impact on the network operation. Nowadays communication through mobile packet networks is becoming more and more important and that is why the second part of this work will focus on the simulation of traffic UMTS networks. It will be simulated by the behavior of individual applications without the use of QoS. Then the application will be assigned to different quality classes and the quality of service will be compared with simulations without using QoS. The conclusion of this work will contain laboratory work, which should partly make the students familiar with the data traffic in the UMTS network through a simulation program – Opnet Modeler.
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Quality of Service Assurance in UMTS Network
Nesveda, Marek ; Novotný, Vít (referee) ; Hošek, Jiří (advisor)
The bachelor´s thesis deals with the assurance of the quality of service (QoS) in UMTS (Universal Mobile Telecommunications System) networks. It consists of theoretic and practical parts. The first, theoretic part first describes the quality of service assurance in general and then focuses on the area of the assurance of the quality of service (QoS) in UMTS network environment specifically. It describes the QoS concept in UMTS, typical UMTS network architecture, its components as well as various QoS classes defined in UMTS. It explains parameters that define the quality of service in UMTS network, and describes call set-up for the purposes of transmission between end users. The second, practical part of the bachelor´s thesis describes how to configure a complex UMTS network simulation model in OPNET Modeler, ver..14.5. It gives a detailed description of how to configure each network component and how to set its parameters, in two different scenarios: first including and then excluding QoS. In conclusion, the thesis summarises the results of the simulation in both scenarios, gives their explanations and compares them graphically.
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Methods for measurement of data network performance and quality parameters
Sukup, Luboš ; Zeman, Václav (referee) ; Novotný, Vít (advisor)
Master thesis involves the development of quality measurement issues and performance parameters in data networks. It describes the main technologies as they affect the quality and performance parameters and the effect of these parameters for voice, video and data services. Next are listed some methods for measuring parameters of the data network.In the practical part is selected one method of measuring network parameters and properties of this method are demonstrated by illustrative examples.
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Implementation of Quality of Service into Wireless Networks
Kaman, Štěpán ; Růčka, Lukáš (referee) ; Škorpil, Vladislav (advisor)
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.
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Signal Processing in Flarion System
Szajkó, Juraj ; Kejík, Petr (referee) ; Hanus, Stanislav (advisor)
Cílem bakalářské práce Zpracování signálů v systému Flarion bylo prostudovat způsoby zpracování signálu ve fyzické vrstvě a architekturu sítě Flarion. Na základě získaných poznatků při studiu fyzické vrstvy bylo za úkolem sestavit v prostředí Matlab model systému a simulace BER v závislosti na poměr vysílaného výkonu a výkonu rušivého signálu. V první části práce je detailní popis fyzické vrstvy Flarionu, probrána je baseband a OFDM modulace, LDPC kódování a frekvenční skákání. V druhém části práce je prostudována architektura sítě, ekvalizace, řízení výkonu, radiových zdrojů, a způsob handoffu. Ve třetí části práce je vytvoření downlink a uplink modelu v Matlab, dále je provedena simulace BER v závislosti na poměr vysílaného výkonu a výkonu rušivého signálu.
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Creation of laboratory exercises in the NS3 enviroment
Štefančík, Matej ; Langhammer, Lukáš (referee) ; Polák, Josef (advisor)
Diploma thesis provides an introduction to the ns-3 network simulator. It describes the basic abstactions and components of the instrument. This work further discusses the theory, which was applied during simulation creation. The concept of unicast, the issue of IP addressing and routing in networks are specificaly analyzed. The practical part is focused on the creation of four laboratory tasks within the scope of Advanced Communication Techniques. The first task is dedicated to the the issue of static unicast routing in the network. It clarifies the impact of metrics on the process of routing. The following task compares the different types of ICMPv4 and ICMPv6 messages. The third task discusses additional functions of the ICMPv6. Specifically, it focuses on five different types of ICMPv6 messages defined by NDP (Neighbor Discovery Protocol) and their role in the network traffic. The last task focuses on ensuring the quality of services (QoS) in wireless networks, by setting priorities and thereby dividing the traffic into different classes. Attention is focused on parameters such as throughput, delay and jitter.
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Network service testing with WAN network emulator and load simulators
Kocáb, Marek ; Krajsa, Ondřej (referee) ; Novotný, Vít (advisor)
The main task of this thesis was to explore the requirements of different telecommunications services on the network parameter, that are packet delay, packet loss, throughput, jitter. Make to test network service with WAN network emulator and load simulators. Next focus was to explore TCP congestion avoidance algorithms and focus on their throughput. The purpose of the first chapter is to introduce Quality of Service (QoS) for VoIP, video conversation, streaming audio, streaming video and data. The second chapter are to explore various types of delay, that are created from the sender through network device, transmission media to the recipient. The third chapter is to introduce NetDisturb application. It is application, that can emulate real properties of the data network and incoming traffic affect example packet delay, packet loss, bandwidth limit and so on. The key objectives of the fourth and fifth part is TCP protocol and TCP congestion avoidance algorithms. Hier are to introduce TCP protocol basic properties, congestion avoidance mechanisms and analysis of TCP congestion avoidance algorithms. In the practical part are created two laboratory exercises. First laboratory exercise is designed on the implementation QoS for various types of traffic. Second laboratory exercise is focused on the analysis TCP congestion avoidance algorithms and their throughput.
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Control plane analysis in 4G mobile networks
Nguyen, Filip ; Krkoš, Radko (referee) ; Novotný, Vít (advisor)
The aim of this paper is to introduce the LTE system, especially with the EPC system. Protocol analysis equipment of the system and the description of the signal at the fundamental procedures such as logging into the system, change the viewing area, handover, paging, etc. and were designed idikátory of system performance EPC.
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Laboratory of Quality of Service
Eltahir Ahmadon, Ahmed ; Kolka, Zdeněk (referee) ; Polívka, Michal (advisor)
The Bachelor's work, you are reading, deals with the issue of VoIP calling and measurement its quality. In the following paragraphs the discussion will be about the basics of networking protocols such as TCP, UPD, IP and SIP, after that a preliminary introduction to QoS issues - ways of measuring voice quality for instance MOS and E-Model. Importance of implementing QoS for VoIP, and QoS parameters used in the proposed services (will be called "mechanisms"), such as Best effort service, Integrated and Differentiated services. Based on these fundamentals points with designed laboratory for quality of service. The laboratory will be aimed at testing the quality of codecs with regard to bandwidth, jitter, delay and packet loss. The solution lies in the fact that, which codecs are actually suitable for the service.
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