This dissertation deals with analysis of current side canal by means of neural network. First part describes basis of cryptografy and dilemma of side canal. In the second part is theoretickly described neural network and correlative analysis. Third part describes practical analysis of calibres of current side canals by means of classifier which uses neural network in Matlab surrounding. This classifier is confronted with classifier which uses correlative analysis.

The aim of this thesis is, firstly, to design and create the measuring environment for the research of electromagnetic side-channel attacks in cryptography; and secondly, to inform readers about the basics of electromagnetic and power side-channel attacks which present effective ways of the modern cryptosystems’ cryptoanalysis. In the theoretical part, the basic side-channel attacks, including their history and models, are described. The main part is focused on the explanation of the basic principles of power and electromagnetic side-channel attacks. Then, the work describes the basic physical principles of electromagnetic fields; and also the methods which can be used to measure the electromagnetic field. An example of the origination of the electromagnetic field in microprocessors is included. In the next part of the work the theoretical foundation necessary for successful implementation of the measurement of electromagnetic fields on the PIC microprocessor is presented. Next part of the chapter is devoted to the AES encryption standard, the activity of which is examined in the practical part. Furthermore, the magnetic probes, designed according to the theoretical knowledge are described. Also the research environment is described in this chapter. The list of measuring instruments used in the practical part is also included. The practical part of the work deals with the implementation aspects designed to achieve the ideal measurement conditions, such as the choice of appropriate probe, the appropriate location and distance between the probe and the measured system, setup of the oscilloscope and signal synchronization. Furthermore, the measured electromagnetic waveforms for selected instructions are presented. After that follows an analysis of the individual rounds of the AES encryption standard; the analysis of whole AES standard is also included. Then, the methods of simple and differential electromagnetic analysis are implemented. With regard to the knowledge gained in the practical part of the work, the possible countermeasures implemented against the power and electromagnetic side channel attacks are described. The final part of the work comprises a brief review of results.

This thesis deals with electromagnetic analysis and applications of electromagnetic side channel. The first and second part describes the basics of cryptography, function of cryptographic module and side-channel attacks. The third part discusses the electromagnetic analysis, construction of probe, a description of the laboratory workplace, the electromagnetic emission of PIC16F84A, AES and preparation for laboratory measurements. The fourth part describes specific laboratory measurements and extracting the useful signal. In the fifth part of the thesis presents the results of processing the measured values, the outputs generated by scripts and found the link between measured curves and AES encryption key. In the sixth part of the thesis are analyzed the basics of defense against side channel attack.

Goal of this thesis is to get familiar with problematics of neural networks and commonly used security protocols in cryptography. Theoretical part of the thesis is about neural networks theory and chooses best suitable type of neural network to use in cryptographic model. In practical part, a new type of security protocol is created, using chosen neural network.

The thesis briefly describes the digital signatures and basic methods (RSA, DSA, ECDSA) for the creation and verification of the digital signature. The method of group signatures designed by Boneh, Boyen and Shacham (BBS) is described in more details as well as the method designed by Bonen and Shacham (BS). The thesis further explores related issue of the implementation of batch signing and verification for the above mentioned methods and their practical application, particularly for systems Vehicular ad-hod network (VANET) and cloud storage in the field of forensic IT. The purpose of the thesis is to determine which of the methods BBS and BS is more suitable for these systems in terms of computational complexity. For this reason, the author created the program for the comparison of methods BBS and BS. The programme compares the time consumption of the methods for signing and verification of incoming messages. The results of the measurement are summarized in the conclusion along with the justification why the particular methods are suitable for the systems.

The main aim of this diploma thesis is to get acquainted with the area of secure authentication and authorization of users in smartphones on the Android platform. Individual types of encoding, authentications, authentication devices and characteristics of QR codes are decribed in the chapters. In the practical part of this thesis the applications are created with an implemented authentication scheme, which is being developed at FEKT VUT in Brno. The client part of the application, that generates QR code, as well as the server part, that verifies the authenticity of the data, are set up.

The presented text deals with designing of a multilingual application and its following implementation in the C++ language. The application encrypts disk volumes with Microsoft Windows system using symmetric cryptography and password authentication, where the password security strength is verified. Securing the sensitive data is one of the important security goals in area of information technology. The symmetric cryptography uses the same key for both the encryption and the decryption and due to its speed it is suitable for the data storage encryption. For the higher security it is possible to encrypt a whole disk volume with sensitive data.

(in English): This thesis describes and compares the most popular algorithms used in information systems. Specifically, there are: Vernam cipher, DES, 3DES, AES, and Blowfish (symmetric cryptography) and Diffie-Hellman key exchange, RSA, ElGamal, McEliece and systems based on elliptic curves (asymmetric cryptography). The thesis deals with the areas of information security, in particular the various security mechanisms (confidentiality, availability, integrity, authentication, authorization and non-repudiation), which are secured by using cryptography. There is also mentioned the theme of standardization, where the responsible institutions and some standards are presented. Described algorithms are compared using several criteria (time, throughput, memory needed for implementation, avalanche effect and key lengths) in the final chapter. Data used for comparison are taken from other studies and scientific materials.

This thesis deals with design and implementation of AES and DES encryption architectures for embedded systems. Architectures are implemented in VHDL language and design for FPGA technology. The proposed implementations are mapped on the Xilinx Spartan 3 technology. Both architectures are applied in simple ECB (Electronic Codebook) scheme with cache memories. A maximum throughput of design DES architecture 370 Mbps is achived with clock frequency of 104 MHz. The throughput of AES architecture at the maximum clock frequency of 118 MHz is 228 Mbps. Compared to software implementations for embedded systems, we achieve significantly higher throughput for both architectures.

This thesis deals with encryption of short text message (SMS) in mobile communication. Introduction is dedicated to overview of the parts of GSM radiotelephone nets and SMS messages transfer . Next chapter is reserved for description of cryptographic methods especially symetric and asymetric encryptografic aproaches. A design of a SMS messages encryption and decryption techniques is in next. For SMS encryption and sign, there is used the asymetric cypher RSA. Encryption use OAEP padding schema. The public key is saved in certificate. The Symbian OS has been choosen as a suitable platform for programming of mobile devices.