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Methods for the measurement of bit rates in data networks
Franc, Jan ; Martinásek, Zdeněk (referee) ; Zeman, Václav (advisor)
The target of this master's thesis were the known methods for testing the quality of transfer parameters of data networks. I have studied the RFC 2544 document to analyze these tests. From that information and by studying other existing web-based applications I was able to design a concept of my own application that will allow to measure basic quality parameters of transfers made through the Internet (the parameters: downstream, upstream, latency, variance of these and a traced route). My application doesn't require any modifications on the user's system. It's built on the server-based programming language PHP and uses the relational database engine MySQL to store measurement and user data. On the client side, it's assisted by the JavaScript scripting language. Both registered users and visitors are allowed to perform the listed measurements. Registered users are able to browse the history of their own benchmark results and also to send messages to others. There is an administrative account to oversee the operations. Another part of my thesis work is an application for Windows that performs the same measurements but does not use JavaScript.
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Random number generator
Zouhar, Petr ; Martinásek, Zdeněk (referee) ; Sobotka, Jiří (advisor)
The thesis deals with issues of random numbers, their generating and use in cryptography. Introduction of work is aimed to resolution of random number generators and pseudo--random number generators. There is also included often used dividing generators on software and hardware. We mention advantages and disadvantages of each type and area of their use. Then we describe examples of random and pseudorandom numbers, mainly hardware based on physical phenomenon such as the decay of radioactive material or use atmospheric noise. The following part is devoted to suggestion own random number generator and a description of its functionality. In the second half of the work we devote to the field of cryptography. We know basic types of cryptographic systems, namely symmetric and asymmetric cryptosystems. We introduce a typical representant the various type and their properties. At the end of the work we again return to our random number generator and verify the randomness generated numbers and obtained cryptograms.
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Side current channel of microprocessors
Obručník, Ondřej ; Hanák, Pavel (referee) ; Martinásek, Zdeněk (advisor)
In this masters's thesis is closely studied questins of current (power) side channel. It deals with attack upon this type of side channels and methods, which can this channel analyse. Also two methods of measurements, which make possible successfully attack, are presented here. Below the work describes progress, which was used for analyse current side channel of chip PIC16F84A. This chip, which was plugged in the circuit in agreement with diagram introduced here, processes step by step variety of programs implementing always other operation, which matches concrete used instruction. In corresponding chapters are introduced resulting values and graphs, which was obtained by measurement.
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Side channel attacks on chip cards
Matějka, Jiří ; Morský, Ondřej (referee) ; Martinásek, Zdeněk (advisor)
This master thesis deals about the issues of chip cards’ side channels. Side channels are new method in cryptanalysis. Unlike classical cryptanalysis, which looks for weaknesses of mathematical structure of algorithms, side channel’s analysis use weaknesses of physical implementation of these algorithms. First part describes chip cards, their usage a security. There is mentioned the issue of cryptographic algorithms and their implementation on smart cards. There are described well-known side channels and examples of their abuse. Practical part of this thesis is focused on a proposal of a laboratory task, which demonstrates power-based side channel attack on smart card. There is designed laboratory workplace for this task, software for measurement and analysis is implemented in development tool LabVIEW. In the last part is this attack realized, the target of this attack is a standard SIM card.
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Internet Connection variants using present TV cable wiring
Lukáč, Michal ; Martinásek, Zdeněk (referee) ; Stančík, Peter (advisor)
This dissertation examines data transfers along the existing lines of cable TV. PLC equipment has been selected as the focus of this examination. The essay examines the question of Multicarrier modulation and focuses more specifically onto the problem of OFDM modulation, which is being used by the selected equipment. It further describes the process of integration of PLC equipment into the cable TV network, modifications of the CATV and the basic topology of the created data networks. The essay also offers a closer look onto a PLC modem and Head End from Corinex that have been used in the implementation of a data network in a selected rural settlement. The author has also raised the issue of the problems connected with cable wires connected with this particular type of data transfers and the solutions of some of the encountered problems. The characteristics of this network have then been measured during normal operation of the created network. Measurements have been carried out in order to determine the transfer speed on a physical and transfer level, the SNR of specific connections and the signal attenuation. The measurements have confirmed the suitability of the used PLC equipment for the purposes of data transfer along the cable TV lines as far as data speed and signal strength was concerned. A map of the particular cable TV lines and the PLC equipment has been included in the attachment.
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Sensors for decentralized system of water purification
Plotěný, Miroslav ; Mácha, Tomáš (referee) ; Martinásek, Zdeněk (advisor)
Main task of the Master Thesis is to study and propose appropriate sensors that can monitor standard operations of small waste treatment plant. This small plants may replace one big central waste water treatment plant, minimizing interference with the human factor and thus reducing the cost of its operation. Master Thesis deals with the sensors for level measurement, air flow, identifying the operator and others. The most important parameter is the quality of drainage water, which can be derived from the amount of ammoniacal nitrogen. This work discusses the possibility of continuous measurements of ammoniacal nitrogen in water and try to select the optimum solution. At the end of the work is carried out experimental measurements are selected ammonia probe to verify the practical features.
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Side channel attacks
Popovský, Michal ; Sobotka, Jiří (referee) ; Martinásek, Zdeněk (advisor)
It is very difficult in real-time breaking the cryptographic algorithms used at present. The Classical cryptoanalysis is based on finding weaknesses in the mathematical structure of the algorithm. Discovery of side channels caused a substantial change in this science. Side-channel attacks are based on incorrect physical implementation of cryptographic algorithms. This new way attack changes notions about cryptography and security of systems. This master´s thesis contains a detailed description of the whole problem of side channels and deals with side-channel attacks on the RSA asymmetric algorithm. This thesis includes the design and realization of laboratory exercise, which is focused on the time attack on the RSA algorithm implementation.
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Software support of education in cryptography based on integer factorization
Vychodil, Petr ; Martinásek, Zdeněk (referee) ; Burda, Karel (advisor)
This thesis deals with new teaching software, which supports asymmetric encryption algorithms based on the issue of large numbers´ factorization. A model program was created. It allows to carry out operations related to encryption and decryption with an interactive control. There is a simple way to understand the principle of the RSA encryption method with its help. The encryption of algorithms is generally analysed in chapters 1,2. Chapters 3 and 4 deals with RSA encryption algorithm in much more details, and it also describes the principles of the acquisition, management and usage of encryption keys. Chapters 5 suggest choosing of appropriate technologies for the creation of the final software product, which allow an appropriate way to present the characteristics of the extended RSA encryption algorithm. The final software product is the java applet. Aplet is described in the chaprers 6 and 7. It is divided into a theoretical and practical part. The theoretical part presents general information about the RSA encryption algorithm. The practical part allows the users of the program to have a try at tasks connected with the RSA algorthm in their own computers. The last part of Java applet deals with the users´ work results. The information obtained by the user in the various sections of the program are satisfactory enough to understand the principle of this algorithm´s operations.
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IMS multimedia services
Dohnálek, Václav ; Martinásek, Zdeněk (referee) ; Mácha, Tomáš (advisor)
This master thesis refers to a new technology in a mobil services IP multimedia subsystem. First, the theoreticl part, refers to the architectury of this technology and elementary protocols. Although it is real-time services, is nesessary to refer about the Quality of Services, that it ensures the condent transmition of data. The second, practisy part refers to a the development background SDS 4.0 FD1 from Ericsson ltd., that it is used develop aplications for IMS technology. It will be to develop the aplication , that it used to the IMS and it refers to the elementary function and comunication.
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Thin device for the real temperature distribution measurement with the negastore matrix
Martinásek, Zdeněk ; Chmelař, Milan (referee) ; Rampl, Ivan (advisor)
The main task of the Master Thesis is to project a device to measure surface temperature distribution by matrix of diodes. The maeasuring device is designed for usage at places where other thermal map scanning measuring methods (e.g. thermocamera) can not be used. The key objective was to design an appropriate measuring method for selected type of sensor. This method should ensure the most effective detection of the changing value, translate received values to the digital form and send it to the computer. All circuits were powered over USB (Universal Serial Bus) together with the signalling. Calibration was needed due to different sensors technical parameters. The calibration was realized on the software level and displayed with the thermal map scanning on the computer. The final project has the form of the measuring installation with 256 sensors on 8x8 cm area.
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