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Measurement of the fiber optical transport links
Ambrož, Jan ; Škorpil, Vladislav (referee) ; Reichert, Pavel (advisor)
This thesis deals with the measurement of optical transport links. In particular, the measurement of attenuation, chromatic and polarization mode dispersion. Specic me- asurement systems using a WDM and passive optical networks. Within each chapter are listed the causes and eects restrictive factors and methods of measurement. In chapter Attenuation measurements are described radiation and material loss as the main causes of depression. Methods whitch are described two lengths, insert loss and reectometri. Chromatic dispersion at dierent speeds of various wavelengths limits systems with high transfer rate. Methods of measuring the phase shift, dierential phase shift, pulse time delay and interference. Polarization mode dispersion is a random phenomenon caused double refraction, must be measured after completion of the route. Scanning wavelen- gth, traditional and general interference, reectometri and the polarimetric are methods of measurement. It described the measurement of WDM systems in three stages of its build. In brief PON networks are presented, with the specicities of the measurement over splitter. Most chapters are supplemented by the results and conclusions of practical measurements. At the end of the work are given by the two standards deal with the measurement of optical transport links.
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The effect of optical fiber attenuation on the capacity of optical traces
Žák, Ondřej ; Škorpil, Vladislav (referee) ; Reichert, Pavel (advisor)
The essence of this thesis is the creation of complex insight on optic fibre attenuation. There is successive steps explained mechanism of optical attenuation and characterized its spectral dependence. We are describing primary elements of optical attenuation, its sorts and their own spectral dependence. Bachelor´s thesis is explaining requirements of transmission system to spectral characteristic optic fibre and influence of optic fibre attenuation on capacity of optical trace. Output of bachelor´s thesis is program solution of designed mathematical model for calcula-tion spectral dependence of optical attenuation. Program is realized in MATLAB and there is furthermore added version in Microsoft Office 1997-2003. Created program is able to ap-proximate points data obtained from measurement of optic fibre by using Lagrange interpola-tion polynomial and Rayleigh scatter interlay.
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Design of passive optical network
Žák, Ondřej ; Münster, Petr (referee) ; Reichert, Pavel (advisor)
Diploma thesis is dealing with access networks, especially with the passive optical network. The theoretical part is a list of different types of passive optical access networks, including theirs basic description, which then goes on to feature connectivity options for optical units, customers, including topology of distribution network. Analysis of different types of networks and the possibility of physical and logical design is the basis for successful design and prepa-ration of future optical access networks. Practical part is devoting to data analysis of measurement existing metropolitan network to be used for construction of optical access network in Brno, Ţlutý kopec – Preslova location. Data evaluation showed possibility of connecting with already installed network hence is created proposal of optical access network mentioned before. Selected location is analysed in detail and illustrated on situational scheme of location and customers, whose will be passive split-ters to central office. Consequently is developed project of optical access network based on data analysed date from measurements. Project is study and description of planned solution of optical access network in order to bring Triple Play services to customers. Within the interpretation of the feasibility of the project and verification physical layer pa-rameters of network was made a simulation in OptiSystem. The possibility of successful op-eration of the optical access network with the attributes entered in its design is approved in accordance with the evaluation results. The proposed network is passive in character of GPON standard, and the text describes in detail physical layer, proposed transmission speed, wave and attenuation plan of optical net-work. The work implies a specific line of HDPE ducts and microducts in them, including drawing the maps and identification in-depth. The work contains a description of the elements that are installed on the route – the number, type and eventually its length. Diploma thesis is introducing the technology and construction sequence of access network leading to its opera-tional state.
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Design and simulation of passive optical network PON
Mikauš, Jiří ; Krajsa, Ondřej (referee) ; Reichert, Pavel (advisor)
The aim of master's thesis was to demonstrate chosen PON network in simulation software OPNET Modeler. The work deals with passive optical networks. In particular, solutions that are based on the transmission of Ethernet frames. EPON and 10GEPON standards are described in theoretical section. EPON Standard was introduced already in 2004. Newer 10GEOPN is back compatible, which is ideal as a suitable solution for modern network with a high data rates demands. The practical part describes process of developing network nodes for passive optical network. EPON model was developed in simulation tool, that demonstrates basic features of the standard IEEE 802.3ah. The simulation results are demonstrated in last section.
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Electromagnetic analysis
Kolofík, Josef ; Reichert, Pavel (referee) ; Martinásek, Zdeněk (advisor)
This thesis deals with electromagnetic analysis and applications of electromagnetic side channel. The first and second part describes the basics of cryptography, function of cryptographic module and side-channel attacks. The third part discusses the electromagnetic analysis, construction of probe, a description of the laboratory workplace, the electromagnetic emission of PIC16F84A, AES and preparation for laboratory measurements. The fourth part describes specific laboratory measurements and extracting the useful signal. In the fifth part of the thesis presents the results of processing the measured values, the outputs generated by scripts and found the link between measured curves and AES encryption key. In the sixth part of the thesis are analyzed the basics of defense against side channel attack.
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The audit methology of optical networks
Štěpán, Petr ; Münster, Petr (referee) ; Reichert, Pavel (advisor)
This work deals with summary of optical system audit in the terms of all layer of the reference model ISO/OSI. Introduction of the work focuses on exploring issues of management networks control, the description of ISO/OSI model and explanation of the terms QoS and SLAs. The description of the optical fiber transmission follows after that. The characteristics of the waveguide and optical communication system components with regard to its reliable operation and management are analyzed. Some major types of optical networks are described. Following section contains a description of methods used in the audit, further the methods for measuring physical, connection and network layer of the reference model are discussed more thoroughly. The work also contains a partial analysis of the audit of the physical layer of the selected section of the Brno academic network optical line. Of all these methods for networks control the final audit report for the optical network with selected limits is compiled as a conclusion of the work.
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FTTx networks
Hradílek, Pavel ; Reichert, Pavel (referee) ; Filka, Miloslav (advisor)
The aim of this thesis is to clarify the issue of optical access networks, and to acquaint the reader with problems of their design and implementation. The introductory chapter describes the technologies and topologies, which are the most experienced in dealing with optical access network. There are a comparison of their basic parameters and limiting factors. Another part of the work is dedicated to progressive methods of construction such as microtubes and solution using the hanging cables, which due to the efficiency of construction, rapidity, economic and facilitate implementation. In conclusion the theoretical part there is issues of measurement. It describes a Optical Loss Test Set, OTDR method and method of measuring dispersion. Increasing demands on the capacity of the transmission paths, and their quality are caused of monitoring optical access networks, which can evaluate the failure on a route, target problems and inform service. The practical part compares EPON and GPON. In program OptiSystem was created model which these technologies are evaluated in terms of performance parameters, noise, jitter and eye diagram quality. The common feature of technology is transmission TDM frames, where EPON uses Ethernet and GPON technologies ATM. The outcome of simulation don´t show which technology is better, but result shows the conditions of the proposal of these technologies. At the end of work there are created several models for solving the optical access network with pricing per user. The most developed technology is FTTB in urban areas, when transmission in last mile uses copper circuit. This solution causing a rapid return on investment. Other technologies such as point-to-point FTTH or PON are implemented as individual proposals. Each of these solutions has advantages and disadvantages, so each project is unique and the solution is dependent on the project site and the requirements of customers.
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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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Parameters of FTTx networks - Quality of services
Winkler, Aleš ; Reichert, Pavel (referee) ; Münster, Petr (advisor)
The main subject of this diploma thesis is to make a proposal to improve the optical access network for the transmission of Triple play services. I would here to the reader clarify method of proposal of optical network. There are described the kinds of optical access networks with parameters, for which we must look by their construction. There are described the modern methods of construction optical network too. In the theoretical part are discussed used architecture of networks too. I met here known standards, which I compared for big importance by their choice. A reason of construction of optical network are services known like Triple play. These services together with their problems and parameters are here discussed too. At the end of theoretical part I listed here measuring method for getting negative attribute distorting the led signal. In practical part the locality witch use the optical signal as the source of information is ordered. These network use unfit connections and has less possibilities than usual and this is the reason, why is the network not able to supply Triple play in requested quality. At first the analysis of ordered network was needed. Situation was complicated by the fact, that it has been prohibited entrance to me. The structure of network and network parts was known and documented by me. I made the proposals to improve this network in practical part. By the first proposal remained original kind of access network FTTB, but used new parts with higher performance. By the second proposal I made the network FTTH, by which it was possible to use the last haul optical cables with treatment and using new elements. It was needed to create solution by flat units. The resulting proposals are here evaluated, compared and cost evaluated. For rejection of access to optical network I did not make measuring, so I made simulation for variant FTTH for getting some parameters negative acting transmission.
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