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High speed mobile access using "Femtocell" solution
Novák, Vladimír ; Molnár, Karol (referee) ; Novotný, Vít (advisor)
This bachelor thesis describes principle of mobile networks, their generation and evolution. The infomation about data transfer and third ganeration of mobile system are written in detail because they are in tight context with main submission of the thesis. Next, the historical and technical information about Femtocells technologie (especially implementation, architecture, solving of providers) are mentioned. In practical part of the thesis the solving of Femtocells technologie for 100 family houses nearby bigger city is realized. Economic confrontation macrocells network with Femtocells component network is described. Calculation of Femtocells cost savings is done.
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Data transmission in mobile networks
Bílek, Petr ; Molnár, Karol (referee) ; Havelka, Dušan (advisor)
The Bachelor’s thesis deals with mapping and usage of mobile networks of data transfers. It describes every particular generation of networks and technologies that they can use. This thesis is divided into two main parts, theological and practical. In the first part, the technologies of the second and third generation currently used for data transfer in mobile networks are described there. This concerns especially GPRS, EDGE and UMTS services. The thesis focuses on modulations used for these technologies, together with the coding and bit rates possible. It compares their advantages and disadvantages and presents their utilization among national operators. It also tries to sketch out the way the data services of mobile networks will proceed. The second part of the thesis is also divided into two parts. The first one is the simulation of the UMTS network with the assistance of the OPNET Modeller 14.5 environment. In this case, the thesis aims at two important characteristics - such as the dependence on the bit rate and distance of the primary station, and dependence on the bit rate and total load of the whole network. Both characteristics are observed mainly because of the bit rate and power characteristics. It describes objects and funcions of the OPNET environment. The next part in the practical section is the factual measurement of the Internet 4G service, provided by T-Mobile operator. The thesis focuses here on the presentation of the outcomes which were accomplished by the practical measurement of that service. The end of this thesis is dedicated to the comparasion of simulated outcomes with the outcomes practically measured, and to the conclusion of the results emerged from them.
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Design and implementation of model architecture of MIB system database
Mikulica, Vladimír ; Hošek, Jiří (referee) ; Molnár, Karol (advisor)
The submetted work deals with the systems design and the implementation of the model database MIB. The work is the introduction into the protocol SNMP (Simple Network Management Protocol) and the database MIB (Management Information Base), which describes in detail branch MIB II. This branch is the current standard for the management of objects using SNMP. Consequently, there are explained different data types that the MIB database uses. Furthermore, the work describes the procedures for the design of the database MIB in the language of ASN. 1 according to RFC 2233 and the subsequent transfer of the MIB database, available through the compilers into the langure C. In the following chapters of the work, each of the models that were created in the simulated environment OPNET Modeler during the implementation of a comprehensive simulation scenario are documented more in detail. The above mentioned parts implement the communication between the manager and the agent. The state machine and the individual blocks of the model are described so that it could be later re-assembled by other candidates.
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IP Multimedia Subsystem and its usage for quality-of-services assurance
Betlach, Michal ; Molnár, Karol (referee) ; Hošek, Jiří (advisor)
The aim of this work is to give information about the structure and elements of the IP Multimedia Subsystem, using signaling protocol and transferring messages between the terminal and elements of IMS. Create model, which implements messages transfer between terminal and IMS elements, by environment tools OPNET Modeler. This work describes system function IMS, its architecture, basic elements, architecture of using signaling protocol SIP and its elements, SIP and SDP messages format and the way of ensuring Quality of Services. There is a project of model terminal registration and reservation data flow by terminal in the IMS. These models were realized in a simulation environment called OPNET Modeler by using tools: project editor, node editor and process editor. In the last part of this work, the method of verification correct function of realized models was created by simulation tools called Debbuger. This tool is one of the environment tools OPNET Modeler.
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Testing of ZigBee wireless modems
Kasper, Robin ; Molnár, Karol (referee) ; Martinásek, Zdeněk (advisor)
This thesis deals with the testing of wireless radio modems CDX800. Modems communicate in the unlicensed 869MHz band and are based on the ZigBee standard. The first chapter is devoted to the description of this standard. Thesis aims to test the modems according to RFC2544 and RFC1242 recommendations for testing networks, which are discussed in the work. For testing of the network in accordance with those recommendations have been selected hardware testers Trend Unipro GbE. Testers are primarily intended for Ethernet networks, and therefore it was necessary to use converters from Ethernet to serial line which modems use to communicate with other devices. Measurements of the testers were unsuccessful by virtue of inappropriate choice of converters. The work shows potential substitute for these converters. Furthermore, the work deals with testing the modems in terms of radio range on the line of sight and in build-up area. For this purpose was chosen service program Radwin. At the conclusion of the work was created network design for decentralized wastewater treatment for the community Podbřezí from the measured parameters. Designed network is composed of 50 stations and one control center.
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Low-level communication with an IP telephone exchange
Švehlík, Martin ; Krajsa, Ondřej (referee) ; Molnár, Karol (advisor)
This bachelor thesis deals with potentiality of low-level communication ways between the Silicon Laboratories Si3220 subscriber line circuit and Marvell PXA270 microprocessor with the Linux operating system installed on it. Following the materials published by the manufacturer, the means of communication between the Si3220 subscriber line circuit and PXA270 microprocessor were examined thoroughly. The dynamically attachable unit for the core of the Linux operating system was created to support read and write operations in the register and RAM address of the Si3220 circuit via the SPI serial interface. For the purpose of verification the test linking between the Si3220 circuit and PXA270 was created and selected registers of the Si3220 circuit were read.
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Modelling of UMTS network resource control
Bednárik, Ján ; Šimek, Milan (referee) ; Molnár, Karol (advisor)
The main aim of my master thesis was to get acquainted with the implementation of quality-of-service support methods in UMTS 3G mobile network and the evaluation of these methods in a simulation environment with main interest in the characteristic features of the traffic classes. The impact of the QoS methods available on different service types were verified in the OPNET Modeler simulation environment. I examined mainly the potentials of the model to support the required quality parameters for the connections. The models of typical network applications, available in real UMTS networks, together with two examples of mobile networks, operating voice and video services in combination with standard data services, were defined in this simulation environment. My work also contains the detailed description of configuration parameters fundamental for correct behavior of the simulation models. The simulation also shows the case, when the transport service is rejected due to the lack of network resources. The key parameters of the model are also described and their effect on the service quality with and without QoS control are compared in separate scenarios. Finally, I investigated the effect of mobility of the end stations on the communication process, especially on the duration of a file transmission.
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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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Mathematical modelling of WWW network traffic
Papšík, Lukáš ; Růčka, Lukáš (referee) ; Molnár, Karol (advisor)
The aim of this thesis was to practically use theoretical knowledge of the semestral work. The scope of work was to analyze long term operation of an emphasis on obtaining the necessary parameters for selected models. Network analyzer was used for two programs that have received the required parameters. How do I edit the captured data that can be used in programs described in the work. In this work I focus on two models, the Stochastic model and Markov-modulated Poisson’s. Each of these models requires different parameters. These were obtained from the captured traffic. Furthermore, the modeled traffic compared with the real. It was found that none of the models is not sufficiently capable of accurately modeling the behavior of the network, if it comes to cluster of packets. However, if traffic shown linear character models were able to model this traffic.
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