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Quality of services and experience qualify for next generation networks
Vaněk, Jiří ; Horváth, Tomáš (referee) ; Grenar, David (advisor)
The thesis sums up the traffic parameters for the evaluation of next-generation access networks. There are mentioned parameters for service quality management and parameters for measuring the quality of experience. The EU regulation on High Speed Internet in the Czech Republic is analyzed. The practical part compares the results between the implementation of the quality management of services and without implementation. Also there is comparing theoretical and practical transmission rates of physical ports. Part of the thesis is a questionnaire focused on the quality of experience of the video sequence.
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Optical network design
Polaček, Adam ; Tomašov, Adrián (referee) ; Horváth, Tomáš (advisor)
This bachelor thesis deals with the design of a technological optical network for the area of Hradec Králové, for the company ČEZD Distribuce. The theoretical part of the thesis describes the current network design and discusses network protocols. The practical part of the thesis describes the passive part and the logical part of the network. An important part of the thesis, is the fiber scheme and configuration design for router and switch. In the last part of the thesis, simulation in GNS-3 program is shown.
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Analysis of GPON frames using machine learning
Tomašov, Adrián ; Horváth, Tomáš (referee) ; Holík, Martin (advisor)
Táto práca sa zameriava na analýzu vybraných častí GPON rámca pomocou algoritmov strojového učenia implementovaných pomocou knižnice TensorFlow. Vzhľadom na to, že GPON protokol je definovaný ako sada odporúčaní, implementácia naprieč spoločnosťami sa môže líšiť od navrhnutého protokolu. Preto analýza pomocou zásobníkového automatu nie je dostatočná. Hlavnou myšlienkou je vytvoriť systém modelov za použitia knižnice TensorFlow v Python3, ktoré sú schopné detekovať abnormality v komunikácií. Tieto modely používajú viaceré architektúry neuronových sietí (napr. LSTM, autoencoder) a zameriavajú sa na rôzne typy analýzy. Tento systém sa naučí na vzorovej vzorke dát a upozorní na nájdené odlišnosti v novozachytenej komunikácií. Výstupom systému odhad podobnosti aktuálnej komunikácie v porovnaní so vzorovou komunikáciou.
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Transmission of accurate time and stable frequency through the optical network
Girt, Lukáš ; Horváth, Tomáš (referee) ; Vojtěch, Josef (advisor)
Diploma thesis focuses on the theoretical analysis of precise time and stable frequency transfer. It describes what time and frequency is, their properites and options of their generation. Next part deals with different possibilities of time and frequency transfer especially using fiber optics. In the practical part equipment for analysing effects of temperature changes on precise time transfer is puted into operation. Arduino platform is used for monitoring temperature changes on fiber. For testing of frequency stability in variable temperature conditions of environmental chamber device is created using highly coherent laser.
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Design of optical access networks
Nguyen, Filip ; Horváth, Tomáš (referee) ; Münster, Petr (advisor)
The aim of this paper is to outline the problems of the design of optical access networks. In the first Rasta work is generally described problems optickcýh GPON network GEPON. The second part deals with the optical network elements, such as HDPE ducts, fiber optic cables, optical splitters and the like. The third part is devoted to legislative operation of electronic communications, especially the work is focused on the rights and obligations of providers elektronickcýh communications. It is also in this part of the studied issues of territorial management in the design of optical access networks. In the last part was designed optical network, for which the development of model documentation to obtain zoning and accompanying technical report, including drawings. The proposed network was prepared in the lab of optical networks and were made to her measurements CD, PMD, OTDR measurement and direct method.
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Simulation and measurement of triple play services in FTTx networks
Horváth, Tomáš ; Münster, Petr (referee) ; Šifta, Radim (advisor)
The aim of this thesis was to ascertain with the measurement methods of passive optical networks and the creation of a simulation model that corresponds to the measured network and comparison of results. The first chapter deals with Triple Play services, which are focused on different services (transmission of television signals, voice and data transmission). Each service consists of a subchapter and presents a detailed description of the parameters associated with the transmission. The second chapter of the theoretical part consists of an analysis of passive optical networks according to termination method of FTTx optical fiber. Partial part of this chapter consists of description of standard passive optical networks APON, BPON, GPON and EPON. The EPON standard is explained in detail. The theoretical part of the thesis is concluded with a description of active elements that will form the laboratory measured network. Testing of designed passive optical network is performed in the practical part of the thesis. The measurement is divided into two chapters. The first chapter consist of measuring of the „inanimate network“, as there are missing active elements in the nominated net. Network measurements were done by a direct measuring method and reflectometric method. The second chapter of the practical part consists of measuring the parameters of quality of service (QoS). This chapter is divided into subchapters, such as: the measurement using RFC 2544 standard, the measurement using ITU-T standard Y.156 (EtherSam) and bit error rate testing (BERT). The practical part ends with a designed simulation network model, which was proposed in OptSim 5.2. The aim of the simulation model was to maximally resemble a real network, due to result comparison.
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Simulation of Triple Play services in passive optical networks with OMNeT++ application
Puchrík, Matej ; Oujezský, Václav (referee) ; Horváth, Tomáš (advisor)
The thesis deals with dynamic bandwidth allocation in passive optical networks of NG- PON2 standard. The paper also describes the so-called. triple play services and the practical part is a simulation of these services in passive optical networks NG-PON2 in the simulation environment OMNeT ++. As part of this work modules for passive optical network NG-PON2 were created as an expansion of project INET. Namely ONU, OLT and splitter modules were created. The first four chapters are theoretical and descibe older standards PON networks, further NG-PON2 networks and DBA algorithm then describes triple play services and explains their current status respectively. In another part a description of the programm OMNeT++ a description of the structure of simulation models. The practical part contains a description of modules, implementation of DBA algorithm and its modification, design simulated topology and detailed description of the configuration simulation. At the end of the practical part presents the results of simulations with the corresponding explanations.
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Security Risks in Passive Optical Networks
Šimoník, Jan ; Jeřábek, Jan (referee) ; Horváth, Tomáš (advisor)
This diploma thesis deals with the historical development of passive optical networks, according to the standards that was defined by International Telecommunication Union (APON, BPON, GPON, XG-PON and NG-PON). Further, the thesis describes the security of passive optical networks, but also a security threats which the deployment and use of passive optical technology carry. In the introductory chapters of this thesis the passive optical networks are described. The following is a description of the standards of passive optical networks in terms of their historical development. The next part is dedicated to the security of passive optical networks and possible security threats. In conclusion a description of the practical part of this thesis is given -- rack assembly, which will serve for future testing. The basic configuration of the optical line terminations that are fitted in the rack is also described. The last part of this diploma thesis is dedicated to the testing of selected security risks, which was described in the theoretical part of this thesis.
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Nonlinear phenomena in optical fibers
Burian, Radek ; Horváth, Tomáš (referee) ; Münster, Petr (advisor)
The subject of this thesis is to describe nonlinear phenomena in the optic fiber. The theoretical part describes a principle of transmission in optical fibers. Optics modules, fibers and their parameters are described marginally. Except nonlinear phenomena, there is also described linear phenomena such as attenuation, dispersion, scattering. In terms of nonlinear phenomena there is described second order phenomena such as Second harmonic generation (SHG), Sum and difference harmonic generation (SFG and DFG) and third order phenomena, such as Kerr effect, Third harmonic generation (THG), Four-wave mixing (FWM) and Cross phase modulation (XPM). There are also described nonlinear scattering, such as Raman´s and Brillouin´s scattering. The Four-wave mixing is simulated in the first half of the practical part. Four-wave mixing occurs in DWMD systems, where can invoke cross-talks between channels. In the second half of the practical part is measured this nonlinear phenomenon. The aim of the measurement is to understand the behaviour of the FWM and find the way how to eliminate its power. The Four-wave mixing measurement is based on the simulation. Second measurement is designed for Brillouin scattering. The conclusion from simulated and laboratory part from both measurements are compared with theoretical knowledge.
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Switches for FTTx - deployment in networks with IPTV
Horváth, Tomáš ; Reichert, Pavel (referee) ; Münster, Petr (advisor)
The aim of this paper was to acknowledge ourselves with the switches which can be used in the networks based on FTTx. The first chapter deals with the IPTV service, its advantages, disadvantages and provided services. In the following chapter, optical fibres and the possibilities of their termination are discussed - FTTH, FTTC, FTTB, FTTO, FTTP and FTTN. The next part involves the methods of broadcasting and more detailed analysis of multicast addresses including defined range and multicast distributional trees. The conclusion of the theoretical analysis of this paper is formed by the explanation of all 3 versions of the IGMP record and the division of switchers through the signals transmitted. In the practical part, the suggestion of testing these switchers is carried out. The first method represents testing through one video file in various resolutions. Another possibility of testing is based on the first method, nevertheless, with the difference that the testing is done in two streams and each one of them has a different data flow. The purpose of the last testing is to demonstrate the fact that the video flow is transmitted through multicast, not every single flow from a server to a client separately. The connection between switchers was reduced to 10 Mb/s and the chosen video file runs at these average transmission data.
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