Security of the SHA-3 candidates Keccak and Blue Midnight Wish: Zero-sum property

The SHA-3 competition for the new cryptographic standard was initiated by National Institute of Standards and Technology (NIST) in 2007. In the following years, the event grew to one of the top areas currently being researched by the CS and cryptographic communities. The first objective of this thesis is to overview, analyse, and critique the SHA-3 competition. The second one is to perform an in-depth study of the security of two candidate hash functions, the finalist Keccak and the second round candidate Blue Midnight Wish. The study shall primarily focus on zero-sum distinguishers. First we attempt to attack reduced versions of these hash functions and see if any vulnerabilities can be detected. This is followed by attacks on their full versions. In the process, a novel approach is utilized in the search of zero-sum distinguishers by employing SAT solvers. We conclude that while such complex attacks can theoretically uncover undesired properties of the two hash functions presented, such attacks are still far from being fully realized due to current limitations in computing power

Mobile e-learning systems

Education is a key element in the life of every person. In the recent years we have seen strong growth and development of information technologies, and as a consequence - informatization process in all areas of society. Particular attention is now being paid to mobile technologies, based on the analysis of the market it has been revealed that tablets and smartphones are one of the most promising areas of development in the near future. The paper presents an approach to design of the e-learning systems in terms of diversity of implementation on the side of the client/end user (mobile application, web application and a classic application for PC). To improve the performance of teachers and students the implementation of special units is suggested, such as the module of the analytical statistics for teachers, the module of additional advanced checking of home work and feedback module