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QoS in IP network with the help of OMNeT++ simulation tool
Hudec, Lukáš ; Mlýnek, Petr (referee) ; Růčka, Lukáš (advisor)
The content of this thesis is giving information about the network simulator OMNeT++ and its superstructure INET Framework. In this thesis a sample simulation of IP network with the help of simulation package INET Framework is realized on this theme. The thesis also deals with analysis of possibilities, how to assure quality service in IP networks and subsequently implementation quality of service in surrounding of network simulator OMNeT++ and its superstructure INET Framework. The implementation is accomplished by two methods. The first method is implementation of differential service, in other words DiffServ, with the help of change the behavior of output. This change rest in sorting of data packets to different queues by their device priority. The second method shows principles of the technology MPLS and also function code protocol OSPF. The MPLS technology is realized by special routers with implemented moduls reservation protocol.
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Modelling of PLC system to ensure the reliability of communication
Procházka, Vít ; Mišurec, Jiří (referee) ; Mlýnek, Petr (advisor)
The master´s thesis is focussed on principles and characteristics of Powerline Communications (PLC), practical usage possibilities and advantages and disadvantage of it. There are described mudulations and a channel encoding which are in PLC used. The main part of the thesis deals with a design of a channel as transfer function through the use of two methods, an echo model and the ABCD matrix. After finishing of the design of transfer function the model of communication was created in the Matlab-Simulink program. There were used the narrowband modulations in the model and analyzed the bit error rate of the tranfer data. In the end all results were treated graphically and evaluated.
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Narrowband PLC communication based on G3-PLC, PRIME and IEEE-1901.2 standards
Skrášek, Tomáš ; Šilhavý, Pavel (referee) ; Mlýnek, Petr (advisor)
Diploma thesis is about narrowband PLC communication standards. The theoretical part describes details of all available OFDM standards including G3-PLC, PRIME, IEEE-1901.2 and G.hnem. The practical part deals with PRIME and G3-PLC standards. In this part is also compared OFDM technology with system of single carrier frequency in environment with real interferences. The last part describes developement of two firmwares for PLC modems Texas Instruments TMDSPLCKIT-V3, which allow UART communication and remote data collection. The thesis also includes Windows application developed to display and save collected data.
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Automated cyber security tester for smart devices in industry
Dávidík, Roland ; Mlýnek, Petr (referee) ; Lieskovan, Tomáš (advisor)
This diploma thesis explains the principle of SCADA systems and describes the DLMS/COSEM protocol. In the next part, it shortly describes the Modbus protocol and details the pros and cons of the Modbus protocol in comparison with the DLMS/COSEM protocol. In the next part, an open-source automated scanner was created. This scanner detects devices in a laboratory network. As the next step, the automated scanner finds out open ports and active services, which run on these devices, and tries to attack HTTP, SSH, and Telnet services. Next, the program checks, whether the found device is a smart-meter device and if it is compatible with DLMS/COSEM protocol. If yes, it checks, if the service is vulnerable to DOS attack and breaker disconnection. Scanner’s findings are presented in a newly created web application. NMAP, Masscan, and Metasploit open-source programs are used in the automated scanner. The whole automated scanner is optimized for the HW device Raspberry Pi with the operating system Raspbian Buster Lite installed. This work also describes the testing of the scanner on the laboratory environment and the results are evaluated afterwards.
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Power quality measuring system
Valenta, Jaroslav ; Mrákava, Petr (referee) ; Mlýnek, Petr (advisor)
This thesis deals with the measurement of power quality. The evaluating quality parameters, data collection systems and transfer technologies will be discussed. The various type of cryptographic algorithms are also described. Cryptographic algorithms, which ensure to secure data communications from remote collection points of measurement, will be realized. These cryptographic algorithms will be realized in MATLAB and C/C++. The last part is focus on designed and implemented a simulation model to telemetry the power quality.
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Data transmission over the distribution network
Mucha, Martin ; Mrákava, Petr (referee) ; Mlýnek, Petr (advisor)
his paper describes the principle of data communication through high-tension lines.Preliminary work examines the transmission system, the types of high-tensionn lines and then disassembling the possibility to transmit data through this system. Then there is interference with the types of data and analysis. It includes the PLC technology, which include types of modulation and error correction methods. The paper deals with the possibilities of PLC modems and their use. The following chapter defines the ways of modeling the high-tensionn lines through which is possible to deduce the transfer function of lines. The work includes practical examples of setting the PLC modems and data transmission from one modem to another. It shall also include practical demonstration of spectrum communication signal during the data transfer.
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Cyber security tester of elements used in industrial networks and energy industry
Březina, Jiří ; Mlýnek, Petr (referee) ; Lieskovan, Tomáš (advisor)
This thesis deals with the issue of security analysis of DLMS/COSEM protocol and exploitation of these vulnerabilities in real Smart Grid environment. Thesis starts with a description of power grids in the past and present, introducing the environment of modern power grids and the smart grid elements used in it this power grids to reader. This is followed by a detailed discussion of the communication protocols that operate in these networks, beginning from the older and more industrially based Modbus protocol to the DLMS/COSEM protocol which is most used today and his various components and security. The most common current models of link vulnerability attacks are also summarized in the paper. The thesis aims to implement a tester that tests the security of smart grid elements, mainly on the vulnerabilities described in the thesis. The tester primarily focuses on the vulnerability called replay attack and evaluating the execution of this attack in a laboratory environment.
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Data communication in distribution systems
Sirotný, Miroslav ; Mlýnek, Petr (referee) ; Mrákava, Petr (advisor)
This project includes a basic overview of concepts as is communication, data communication and distributed to systems. Further focuses on the technology use for remote data collection. Part is dedicated PLC technologies, which use systems for remote data collection. The thesis is also mentioned the concept of quality of electrical energy and standard ČSN EN 50160. The main part is focused on the design, implementation and measurement of the PLC network.
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Distribution network models
Hrabčík, Oldřich ; Mišurec, Jiří (referee) ; Mlýnek, Petr (advisor)
This thesis deals with transmission of data over power-line. There is theoretically described PLC technology and its classification, properties and used modulation techniques. A substantial part is focused on the mathematical description of distribution network using two methods, with multipath propagation and ABCD matrix. These methods are mutually compared. Furthermore, they are examined depending on the transfer functions of the topology and capabilities for unknown topology. Calculations of transfer functions are implemented using Matlab. The results were then processed graphically and evaluated.
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Design and implementation of a wireless transmission system using USRP
Vaclík, Michal ; Mlýnek, Petr (referee) ; Krajsa, Ondřej (advisor)
This thesis is focused on design and possibilities of implementation of modular wireless communications system based on software defined radio. This system uses USRP1 kits from Ettus Research and is controlled by GNU Radio Companion software. Final Python script is used to controll and modify parameters of modulation schemes, encoder properties and used bitrate. Thesis also describes possibilities and challenges of using radio HW for transmitting and receiving. Final chapter summerizes and analyzes achieved transmission qualities.
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