Thesis (M.S.)--Brigham Young University. Dept. of Computer Science, 2006. / Includes bibliographical references (p. 41-44).

Thesis (Ph. D.)--University of Hong Kong, 2006. / Title proper from title frame. Also available in printed format.

Thesis (M.S.)--Brigham Young University. Dept. of Computer Science, 2006. / Includes bibliographical references (p. 48-51).

Thesis (M.S.)--Rochester Institute of Technology, 2007. / Typescript. Includes bibliographical references (p. 67-69).

Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.

Thesis (M.S.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains vii, 67 p. : ill. (some col.), col. map. Includes abstract. Includes bibliographical references (p. 65-67).

Thesis (Ph.D.)--University of Idaho, 2006. / Major professor: Jim Alves-Foss. Abstract. Includes bibliographical references (leaves 82-86). Also available online in PDF format.

This research explores the problem of finding a preimage — an input that, when passed through a particular function, will result in a pre-specified output — for the compression function of the SHA-1 cryptographic hash. This problem is much more difficult than the problem of finding a collision for a hash function, and preimage attacks for very few popular hash functions are known. The research begins by introducing the field and giving an overview of the existing work in the area. A thorough analysis of the compression function is made, resulting in alternative formulations for both parts of the function, and both statistical and theoretical tools to determine the difficulty of the SHA-1 preimage problem. Different representations (And- Inverter Graph, Binary Decision Diagram, Conjunctive Normal Form, Constraint Satisfaction form, and Disjunctive Normal Form) and associated tools to manipulate and/or analyse these representations are then applied and explored, and results are collected and interpreted. In conclusion, the SHA-1 preimage problem remains unsolved and insoluble for the foreseeable future. The primary issue is one of efficient representation; despite a promising theoretical difficulty, both the diffusion characteristics and the depth of the tree stand in the way of efficient search. Despite this, the research served to confirm and quantify the difficulty of the problem both theoretically, using Schaefer's Theorem, and practically, in the context of different representations.

D.Com. (Informatics) / The complexity of modern computer-based information systems is such that, for all but the simplest of examples, they cannot be produced without a considerable amount of prior planning and preparation. The actual difficulties of trying to design, develop and implement complex computer-based systems have been recognised as early as the seventies. In a bid to deal with what was then referred to as the "software crisis", a number of so- called "methodologies" were advocated. Those methodologies were, in turn, based on a collection of guidelines or methods thanks to which their designers could eventually make the claim that computer systems, and in particular information systems, could be designed and developed with a greater degree of success. By using a clear set of rules, or at least reasonably detailed principles, they could ensure that the various design and development tasks be performed in a methodical, organ ised fashion. Irrespective of the methodologies or guidelines that were adopted or laid down, the developers principal aim was to ensure that all relevant detail about the proposed information systems would be taken into account during the long and often drawn-out design and development process. Unfortunately, many of those methodologies and guidelines date from the early 1970s and, as a result, no longer meet the security requirements and guidelines of today's information systems. It was never attempted under any of those methodolog ies, however, to unriddle the difficulties they had come up against in information security in the domain of system development . Security concerns should however, form an integral part of the planning, development and maintenance of a computer application. Each application system should for example, take the necessary security measures in any given situation.

D.Phil. / Virtualization is a new infrastructure platform whose trend is sweeping through IT like a blaze. Improving the IT industry by higher utilization from hardware, better responsiveness to changing business conditions and lower cost operations is a must have in the new generation of virtualization solutions. Virtualization is not just one more entry in the long line of “revolutionary” products that have hit the technology marketplace. Many parts of the technology ecosystem will be affected as the paradigm shifts from the old one-to-one correspondence between software and hardware to the new approach of software operating on any hardware that happens to be most suitable to use at the time. This brings along with it security concerns, which need to be addressed. Security evolving in and around the virtualized system will become more pertinent the more virtualization is employed into everyday IT technology and use. In this thesis, a security model for virtualization will be developed and presented. This model will cover the different facets needed to address virtualization security.