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Alternative methods in cryptology
Hampl, Dalibor ; Doležel, Radek (referee) ; Hajný, Jan (advisor)
In the first part of this thesis explains, what is generally cryptography, generally analyze the problem of the current encryption methods. These include asymmetric, symmetric and hybrid encryption methods. The second part focuses on the theory of lattices and their main mathematical problems, then the shortest vector problem, the closest vector problem, the approximate shortest vector problem and the approximate closest vector problem. Mathematically difficult problems of lattice are used in an encryption method GGH for asymmetrically encrypted communications method and GGH for digital signatures. It explains mathematical methods, which use these encryption methods. Another part of this thesis deals with the encryption method and the establishment of XTR on Diffie-Hellman protocol, thus XTR-DH. It explains mathematical methods, which use methods XTR, XTR-DH and Diffie-Hellman protocol. There are shown the main mathematical problems for this part of thesis DHP (Diffie-Hellman problem) and DLP (discrete logarithm problem). The fourth part focuses on a program designed to demonstrate the GGH encryption method for asymmetrically encrypted communications. Describes the structure, functionality, graphical part of the program and shows to a user interface. Students can test how the GGH encryption method behave when entering different input values. During the work with the program, the user should obtain sufficient information to understand the principles of this encryption method.
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Security design for system of remote quality measurement of electric power
Jakubíček, Michal ; Koutný, Martin (referee) ; Mlýnek, Petr (advisor)
Bachelor thesis in the first chapter deals with the concept of quality of electric power and its parameters. The next chapter is focused on systems that used remote data collection and the current direction of evolution of these systems. The third of the thesis discusses the symmetric and asymmetric cryptographic systems and their main representatives. The asymmetric system is described by the principle of calculating RSA and Diffie–Hellman. The next part deals with selected libraries that can count large numbers. Through the establishment of key using the Diffie–Hellman with these libraries and the subsequent measurement should be proved whether optimized library is faster than the other libraries. The evaluation of the used library in terms of speed and memory consumption is inculded in the final chapter. The appendix include installation instructions for the libraries BigDigits, GMP and OpenSSL in Visual Studio 2010.
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Security design for system of remote quality measurement of electric power
Jakubíček, Michal ; Koutný, Martin (referee) ; Mlýnek, Petr (advisor)
Bachelor thesis in the first chapter deals with the concept of quality of electric power and its parameters. The next chapter is focused on systems that used remote data collection and the current direction of evolution of these systems. The third of the thesis discusses the symmetric and asymmetric cryptographic systéme and their main representatives. The asymmetric system is described by the principle of calculating RSA and Diffie–Hellman. The next part deals with selected libraries that can count large numbers. Through the establishment of key using the Diffie–Hellman with these libraries. The evaluation of the used library in terms of speed, number of elementary cycles and memory consumption is inculded in the chapter 5. The last chapter explains the optimization focused on Ultra-Low Power MCU and shown Montgomery multiplication and squaring. It describes in detail the procedure of calculation and described why is his calculation faster than conventional modular multiplication and exponentiation. The appendix include installation instructions for the libraries BigDigits, GMP and OpenSSL in Visual Studio 2010.
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Software support for cryptography system training based on discrete logarithm
Kříž, Jiří ; Zeman, Václav (referee) ; Burda, Karel (advisor)
Current needs of human communication came to status, when most of transferred messages are considered as private and transition over non-secured communication lines in open form is not possible. That originated a lot of different methods for securing of messages and transfers in ciphered form. Two mainstreams were established, symmetric cryptography and asymmetric cryptography. Second of mentioned groups is based on usage of two information – keys, when one of then is broadly known and is public and second, well protected and private. Using a public key it is possible to establish a cryptogram of message, but for deciphering it is necessary to know private key. Asymmetric methods are based on mathematical problems, for which there is not an effective computing algorithm. This thesis are focused for asymmetric cryptosystems based on discrete logarithm problem, where ciphering of message using public key is very easy and quick, but deciphering without knowledge of private key is extremely time consuming process. Work describes a mathematical base of discrete logarithm problem, its’ properties and methods developed for solving of this problem. Descriptions of particular cryptosystems are given, i.e. ElGamal cryptosystem, Diffie-Hellman protocol and DSA. Second part of thesis is focused for web application developed as study support of discrete logarithm problem and of cryptosystems using this problem. It describes functional and graphical interface, work with it and options given to user working with application. Mentions also lessons for user which should help with understanding of described problems and practicing.
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|
|
Security design for system of remote quality measurement of electric power
Jakubíček, Michal ; Koutný, Martin (referee) ; Mlýnek, Petr (advisor)
Bachelor thesis in the first chapter deals with the concept of quality of electric power and its parameters. The next chapter is focused on systems that used remote data collection and the current direction of evolution of these systems. The third of the thesis discusses the symmetric and asymmetric cryptographic systems and their main representatives. The asymmetric system is described by the principle of calculating RSA and Diffie–Hellman. The next part deals with selected libraries that can count large numbers. Through the establishment of key using the Diffie–Hellman with these libraries and the subsequent measurement should be proved whether optimized library is faster than the other libraries. The evaluation of the used library in terms of speed and memory consumption is inculded in the final chapter. The appendix include installation instructions for the libraries BigDigits, GMP and OpenSSL in Visual Studio 2010.
|
|
|
Security design for system of remote quality measurement of electric power
Jakubíček, Michal ; Koutný, Martin (referee) ; Mlýnek, Petr (advisor)
Bachelor thesis in the first chapter deals with the concept of quality of electric power and its parameters. The next chapter is focused on systems that used remote data collection and the current direction of evolution of these systems. The third of the thesis discusses the symmetric and asymmetric cryptographic systéme and their main representatives. The asymmetric system is described by the principle of calculating RSA and Diffie–Hellman. The next part deals with selected libraries that can count large numbers. Through the establishment of key using the Diffie–Hellman with these libraries. The evaluation of the used library in terms of speed, number of elementary cycles and memory consumption is inculded in the chapter 5. The last chapter explains the optimization focused on Ultra-Low Power MCU and shown Montgomery multiplication and squaring. It describes in detail the procedure of calculation and described why is his calculation faster than conventional modular multiplication and exponentiation. The appendix include installation instructions for the libraries BigDigits, GMP and OpenSSL in Visual Studio 2010.
|
|
|
Alternative methods in cryptology
Hampl, Dalibor ; Doležel, Radek (referee) ; Hajný, Jan (advisor)
In the first part of this thesis explains, what is generally cryptography, generally analyze the problem of the current encryption methods. These include asymmetric, symmetric and hybrid encryption methods. The second part focuses on the theory of lattices and their main mathematical problems, then the shortest vector problem, the closest vector problem, the approximate shortest vector problem and the approximate closest vector problem. Mathematically difficult problems of lattice are used in an encryption method GGH for asymmetrically encrypted communications method and GGH for digital signatures. It explains mathematical methods, which use these encryption methods. Another part of this thesis deals with the encryption method and the establishment of XTR on Diffie-Hellman protocol, thus XTR-DH. It explains mathematical methods, which use methods XTR, XTR-DH and Diffie-Hellman protocol. There are shown the main mathematical problems for this part of thesis DHP (Diffie-Hellman problem) and DLP (discrete logarithm problem). The fourth part focuses on a program designed to demonstrate the GGH encryption method for asymmetrically encrypted communications. Describes the structure, functionality, graphical part of the program and shows to a user interface. Students can test how the GGH encryption method behave when entering different input values. During the work with the program, the user should obtain sufficient information to understand the principles of this encryption method.
|
|
|
Software support for cryptography system training based on discrete logarithm
Kříž, Jiří ; Zeman, Václav (referee) ; Burda, Karel (advisor)
Current needs of human communication came to status, when most of transferred messages are considered as private and transition over non-secured communication lines in open form is not possible. That originated a lot of different methods for securing of messages and transfers in ciphered form. Two mainstreams were established, symmetric cryptography and asymmetric cryptography. Second of mentioned groups is based on usage of two information – keys, when one of then is broadly known and is public and second, well protected and private. Using a public key it is possible to establish a cryptogram of message, but for deciphering it is necessary to know private key. Asymmetric methods are based on mathematical problems, for which there is not an effective computing algorithm. This thesis are focused for asymmetric cryptosystems based on discrete logarithm problem, where ciphering of message using public key is very easy and quick, but deciphering without knowledge of private key is extremely time consuming process. Work describes a mathematical base of discrete logarithm problem, its’ properties and methods developed for solving of this problem. Descriptions of particular cryptosystems are given, i.e. ElGamal cryptosystem, Diffie-Hellman protocol and DSA. Second part of thesis is focused for web application developed as study support of discrete logarithm problem and of cryptosystems using this problem. It describes functional and graphical interface, work with it and options given to user working with application. Mentions also lessons for user which should help with understanding of described problems and practicing.
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