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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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Design of FTTx optical access network
Münster, Petr ; Tejkal, Vladimír (referee) ; Reichert, Pavel (advisor)
The aim of this work is an overview of the proposal for FTTx Optical Access Networks. In the introductory chapter written about the optical fiber and the transmission. Furthermore, as already discussed various options with regard to the implementation instead of the end of optical fiber - FTTN, FTTC, FTTP, FTTB, FTTH and standards, which are used to build fiber optic networks. The next chapter is an overview of the network elements that are in different layers reference model ISO / OSI used. The final theoretical chapter is devoted to progressive technologies for the construction of optical access networks, which has recently been used. Concepts are explained as HDPE pipe, microtubing or self-supporting cables. The practical part design model, passive optical networks in the area Slavičín, located in the Zlín region. FTTB architecture was chosen, where for each connection object is used in the existing copper lines. The proposed route will use a standard technology GEPON Wavelength division WDM, so to connect the individual buildings will be used only one thread. Realization of optical networking technology will be excavation. The optical cables and optical fiber bundles are protected by HDPE pipes stored in the bed of sand. For the optical signal split into multiple lines will be used by an optical splitter 1 / 16, located in an outdoor cabinet optic pathway. The distribution of signals for the settlement will take care Alloptic central station, which is optimized for the transmission of Triple Play services. On the basis of the proposal is to created a financial analysis that shows the return on the project. An important part of the network is also monitoring the network. The last part of this work therefore deals with the possibilities of monitoring networks in order to continuously monitor the network, in order to prevent any disturbances or quickly respond to network problems.
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Measuring methods of key parameters in optical networks
Balon, Jiří ; Reichert, Pavel (referee) ; Tejkal, Vladimír (advisor)
The main goal of the master’s thesis was to familiarize with optical networks dilemma and its measuring during fabrication. The whole thesis is divided into several parts where the first part deals with optic fiber dilemma. It describes its kinds, properties and also suggests a basic principle of optic signal dispersion using these fibers. It describes also optical network FTTx architecture (Fiber To The x). The second part of the thesis focuses on methods of measuring key parameters of optical networks. Is brings out the methods of measuring optical loss and dispersive influences. The last and final part in focused on creating a methodical manual for measuring these networks during its fabrication and verifying measuring methods stated in the theoretical part inside a real network. Measuring was implemented on an optical network of Masaryk University in Brno.
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Techniques solving the fiber optic dispersion on current optical links
Prášil, Jiří ; Pfeifer, Václav (referee) ; Reichert, Pavel (advisor)
This diploma thesis deals with analysis of current diagnostic methods of optical networks, and it is focused on optical fiber dispersion in singlemode fibers. The work starts with a describtion chromatic dispersion and polarization mode dispersion, causes of and thein influence on the transmitted signal at the beginning. There are set out principles and their appropriate use in the list of measuring methods. Furthermore, the work are given the current possibilities for compensation above dispersions. The sixth chapter deals with the measurements and simulations of real routes in the OptiSystem. There are given appropriate compensation methods for the selected route speeds in the last chapter. The simulation is performed for the bit rate 2.5 Gbit / s, 10 Gbit / s and 40 Gbit / s.
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The data transfer technologies in optical access networks (FTTx)
Matušík, Lukáš ; Míča, Ivan (referee) ; Reichert, Pavel (advisor)
The objective of diploma thesis is describe problems connected with designed of FTTX networks and bring the reader problems of data transmission in optical acces networks the type of PON. In the introduction are mentinoned individual technologies that already operate, and there are describe advantages disadvantages of the use topology point-to-point and point-to-multipoint. In the following chapters are dealt with problems with data broadcasting in the direction from final participant. In the other part of diploma thesis are described elements, that were used for the proposed transmission route. The own PON acces network was presented on the basis information obtained by comparing the various networks and the elements involved in them. The network presented in conclusion diploma thesis is involved in topology point to multipoint. This transmission route is simulated in the program that allows the involvement of network by the user’s need with real values. The acces network is simulated for different transmission speed and different distances. The assesment of created optical route results from the measured values, theirs source is program OptiSystem, these values are summarized in the final chapter.
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FTTx network design
Tejkal, Vladimír ; Němec, Karel (referee) ; Reichert, Pavel (advisor)
The main goal of this diploma thesis was to implement the proposal of optical access networks in the selected location. Introduce is focused on the physical layer of network. This includes optical fibers, optical cables, connectors, optical splitters, and more. According to the place of termination of optical fiber will be studied best FTTx connections. According to network topology distinguished point to point and point to multipoint network. Networks points to point are also known as an active optical network and for each user are restricted to a separate fiber. Point to multipoint networks known as passive optical network. In terms of the PON is defined by many standards. For a selected location will be choice the most appropriate solution. Finally, the measurement will be made and will be considered for monitoring the route. Before the design of optical access networks, I made an illustrative simulation in program OptSim. Performed simulations helps to study the transmission characters of optical networks, depending on the physical architecture. In general, for the design of high-capabilities networks for large companies will be more appropriate active topology that provides due wavelength multiplexes high transmission capacity. To join in the urban areas with a large number of separate houses, it is more appropriate use of passive topology. For the design of optical networks has been selected location with multiple housing buildings. The end customer is not given the requirement for high data transfer rates as large companies. For the proposal was selected FTTB networks which is suitable because of lower costs. The second variant of the proposal was a passive optical network according to standard GPON. This standard was chosen because of the high splitting ratio. For both solutions was developed the entire proposal by ITU-T with a detailed drawing documentation. In the selected area was conducted measuring the optical networks in order to verify the possibility of extension actual solutions. For a sample issue of measurements, I made several measurements using optical reflectometer over an optical splitter in order to prove the need for measurements during construction. FTTH networks gaining in popularity more and more, but price is the limiting factor.
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Modelling of advanced 802.11e technology features in OPNET Modeler environment
Šeliga, Michal ; Reichert, Pavel (referee) ; Molnár, Karol (advisor)
This master thesis includes a short review of the structure of WLAN (Wireless Local Area Network) technologies 802.11a/b/g, the description of their physical interface and the description of the basic medium access control mechanisms implementing the PCF (Point Coordination Function) and DCF (Distributed Coordination Function) methods. I mainly focused on the detailed evaluation the new 802.11e standard which was designed to efficiently support real-time services in wireless environment. To provide QoS (Quality of Service) support, this standard specifies the EDCA (Ehanced Distributed Channel Access) and HCF (Hybrid Coordination Function) medium access control methods for the shared wireless environment. The next chapter of my work is devoted to the verification of the theoretical results in OPNET Modeler simulation environment. I studied in details the WLAN model available in OPNET Modeler, the effect of data-flow classification into separate categories and the configuration of several access method parameters. Next, I created my own WLAN model according to the 802.11e standard. This model contains four applications two of them with real-time requirements. The model is divided into several scenarios, each focusing on different aspects of wireless network technologies like QoS support and it´s dependency on the number of clients, mobility of wireless terminals and comparison of the 802.11a/b/g and the 802.11e technology.
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Methodology for FTTH optical network measurement
Gajdoš, Jaroslav ; Reichert, Pavel (referee) ; Filka, Miloslav (advisor)
The main topic of this master thesis is a FTTH measurement methodology of optical networks and its specific features 9 compared with other measurement methodologies. Also, the use of the FTTH measurement methodology: an example of measurements of a passive network with splitter 1:8 and analysis of the results of these experimental measurements. The first part of the thesis concerns itself with the description of optical networks and characteristics and features of the FTTH networks. A detailed description of the passive optical networks is provided: e.g. the optical network unit ONU, the optical line termination OLT, and, most importantly, the passive optical splitter. The wavelength division multiplex 9 WDM 9 which is used in passive optical networks is also described in detail. The chapter on measurement methodologies focuses in detail and provides many examples of currently used measurement methodologies of these networks. The best results are currently achieved with the OTDR methodology. The second part of the thesis concentrates on the description of the measurement of a passive optical network with splitter 1:8 using the methods described in previous chapters. As conclusion, a detailed analysis, assessment of the results and their usefulness when put into practice is provided.
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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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FTTB Network Design
Reichert, Pavel ; Křepelka, Václav (referee) ; Filka, Miloslav (advisor)
The purpose of this master’s thesis is to explain the issues of the FTTx network design. The main idea of this work is to describe to readers the methods of the designing the optical access networks. Especially we will speak about the building technologies and different topologies used in a practice. The different technologies of optical access networks’ building and various parameters, which are necessary to take into account in the designing of these networks, will be introduced. In the theoretical part, methods of measurement, which are like the needed part of each optical access networks’ building, will be described. Two purposes of the FTTB networks with all proprieties will be made and offered. One purpose will be solved by Point to Point topology and the second purpose will be solved by Point to Multipoint topology. Following the confrontation one of these purposes will be chosen and realized. By ITU recommendation, measurements will be performed on the built optical trace. The final protocols will be elaborated from these measurements. The built trace with all final reports will be prepared for assignment to the subscriber.
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