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Quality of service support in unix-like operating system for communication in WiFi networks
Mizera, Josef ; Komosný, Dan (referee) ; Novotný, Vít (advisor)
Diploma thesis is focused on the supporting of Quality of Services in wireless networks, especially in the Linux operation systems. The topic is connected not only with OS, but also with the wireless standard, which supports QoS in wireless networks called IEEE 802.11e. QoS is needed especially for time-consuming data transfers in real time. The theoretical part deals with the theoretical analysis of the issue of the QoS support. There are described parameters, which occurred in quality of services support. This section also deals with the division of services that are used to transmit data across computer networks. It also describes the QoS support in wireless networks according 802.11e, its implementation and methods of accessing a medium with a without possibility of traffic. This part is followed by a description of QoS support in UNIX operating systems. The chapter describes how is the QoS support designed in these operating systems. There are also characterized concrete tools which are used for control the data flow in the operating systems using Linux. At the end the theoretical part deals with different types of queues and methods used in linux OS. In the practical part of the thesis, there are various designed topologies and scenarios to verify the functionality of QoS support in wireless networks using a Unix system. These chapters show the results of different tests at selected transmission data streams that are sensitive to transmission time. There is also verified cooperation of QoS support between devices operating on the network and data link layers. The output of this work is to design a laboratory exercise for the subject Network Architecture. This exercise is focused on familiarization with the QoS support functionality in wireless networks and in Unix-like operating systems. This chapter also describes the devices and programs that are needed to measure this task. The last part of the chapter describes the procedure for the preparation of the measuring station. For this laboratory task, there is an inserted manual in the annex.
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Implementation of Network Security Algorithms in Home Router
Procházka, Tomáš ; Novotňák, Jiří (referee) ; Košař, Vlastimil (advisor)
This bachelor thesis briefly describes minimalist linux distribution OpenWRT and its installation in Linksys WAG160Nv2 router. It describes a selected router and it discusses a measuring procedure of a throughput, wich was chosen as a criterion for an evaluating the performance of the router. Furthermore, it examined the performance of the router using the original system and running OpenWRT. Design and implementation of interception algorithms, whose main purpose is to capture network traffic on the router, are described in the subsequent parts. Results are presented in the final part.
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Implementation of HDLC protocol in network simulators
Polášek, Jaromír ; Mašek, Pavel (referee) ; Pokorný, Jiří (advisor)
This diploma thesis deals with the possibility of using HDLC (High-Level Data Link Control) protocol for communication and addressing of smart metering devices with a data concentrator. The HDLC protocol is used in two DLMS/COSEM (Device Language Message Specification/Companion Specification for Energy Metering) communication profiles. To simulate these communication profiles, the most appropriate simulation program is selected. Using this simulator, the first communication profile is implemented and the second one is designed. Communication profile based on TCP/IP (Transmission Control Protocol/Internet Protocol) has been fully implemented. To implement the three-layer HDLC communication profile, all options have been thoroughly explored. Using these findings, a process was designed to guide the full implementation. For the first communication profile the qualitative parameters are measured, which are then plotted and evaluated.
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Analysis of Sharing Networks
Blažek, Libor ; Mašek, Pavel (referee) ; Horváth, Tomáš (advisor)
The aim of the thesis is the design and implementation of the protocol in OPNET Modeler. In this work will be developed all the elements have been used no default settings. In the first chapters, making simulation are defined packets. Another chapter consists of a block diagram of workstations, which are assigned to function blocks. The central process is created by the process model, also for the router. The individual elements are inserted into a variety of elements and subsequently used in the simulation. Connection is a new service that has been defined separately. One of the simulations will be created on a smaller scale and the other on a global scale with more features.
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Comparison of HomePlug broadband systems and DS2 technology PLC
Horáček, Lukáš ; Zeman, Václav (referee) ; Mišurec, Jiří (advisor)
This thesis comparing broadband systems HomePlug and DS2 PLC technology (Power Line Communications). PLC is a technology for transmitting data over electrical power distribution network. The theoretical part consists of describing a system for broadband data communication over high-tension lines, the selection criteria, a description of DS2 and HomePlug (variants of chips, version, network architecture, elements). There are also described modulation techniques, interference, standards, standard ISO 50065 and access methods. The practical part consists of laboratory measurements with both systems. For the testing were used DS2 modems from the company Defidev and HomePlug modems from AirLive. These are then compared according to selected criteria.
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The visibility identification on aerodromes in Czech Republic
Smetka, Adam ; Hudec, František (referee) ; Krška, Karel (advisor)
This work deals with the visibility and its breakdown by weather vocabulary. It discusses the development of RVR systems at airports in the Czech Republic, describes the measurement systems RVR MITRAS, MIDAS IV and history of selected airports. Other chapters describe the possible development of measurement techniques in RVR. The final section is devoted to the categories of runways.
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Optimization of WiFi Distributed Nets
Žlůva, Ivan ; Krejzlíková, Libuše (referee) ; Matoušek, Radomil (advisor)
This thesis describes theoretic proposal and two practical realization of multi - point wireless network, first for communications between two endpoints and second for wireless signal coverage of a structured space. The wireless network is realized by the equipment working in unlicenced 2,4GHz and 5GHz ISM band. The wireless device are configured in three different wireless mods: WDS, WDS bridge and AP. This paper contains short information about IEEE 802.11a/b/g/n standard and associated proprietary wireless specifications. Practical workshop describes several variants connections and present the result of throughtput measurements, depending on wireless network topology.
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Network tester
Štainer, Martin ; Člupek, Vlastimil (referee) ; Zeman, Václav (advisor)
The objective of this thesis is the issue of network parameters measuring. Measurement methodology and tester concept were designed. Based on the designed tester concept a plugin for Apache JMeter was implemented. Two experimental tests were run based on the methodology designed, with their objectives set to explore the difference in performance between QUIC and TCP protocols.
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Performance Testing and Analysis of Qpid Dispatch Router
Stejskal, Jakub ; Rogalewicz, Adam (referee) ; Fiedor, Tomáš (advisor)
Výkonností testování aplikací nabírá v poslední době na důležitosti během vývoje všeho druhu. Tato práce mapuje základy testování výkonu, které jsou aplikovatelné na libovolné aplikace a následně analýzuje testování výkonu komponent používaných v Messaging systémech a to konkrétně Apache ActiveMQ Artemis a Qpid-Dispatch. Využívané metody testování výkonu je zaměřeno zejména na Apache ActiveMQ Artemis pomocí systému Messaging Performance Tool s názvem Maestro. Práce navrhuje vylepšení této aplikace o rozšíření testování systému Qpid-Dispatch a její možnosti při automatizovaném testování. Řešení je demonstrováno na sérii experimentů s různými topologiemi. Výsledná zpráva závěrem vyhodnocuje navržené rozšíření systému Maestro, zhodnocuje výkon komponenty Qpid-Dispatch a rozvíjí myšlenky pro další rozšíření.
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Analysis of the dependence of communications services to the delay and QoS optimization
Schön, Martin ; Číka, Petr (referee) ; Hošek, Jiří (advisor)
This thesis discusses wireless network standards 802.11a/b/g/n. First part explains basic principles of networks and media access. Next the standard IEEE 802.11, general QoS parameters and their application in wireless networks, according to standard 802.11e are analyzed. Second part of the thesis verifies the acquired knowledge in simulating program Opnet - effects of the delay, jitter and packet loss on VoIP call are tested. In the last part of the thesis a network for video streaming has been designed. The video was streamed in different qualities and the influence of other network traffic (with and without the support of QoS) on the video streaming was tested.
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