Thesis (Ph. D.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2006. / Bertrand Boussert, Committee Member ; Douglas B. Williams, Committee Member ; William T. Rhodes, Committee Member ; Yves Berthelot, Committee Member ; David S. Citrin, Committee Chair.

Thesis (M.S.)--University of Florida, 2002. / Title from title page of source document. Includes vita. Includes bibliographical references.

Thesis (Ph. D.)--University of Washington, 2005. / Vita. Includes bibliographical references (p. 132-142).

Thesis (M.S.)--Ohio University, March, 2004. / Title from PDF t.p. Includes bibliographical references (p. 90-91)

Thesis (M.S.)--Rochester Institute of Technology, 2006. / Typescript. Includes bibliographical references (p. 171-175).

Thesis (M.S.)--Florida State University, 2006. / Advisor: Mike Burmester, Florida State University, College of Arts and Sciences, Dept. of Computer Science. Title and description from dissertation home page (viewed Sept. 26, 2006). Document formatted into pages; contains viii, 54 pages. Includes bibliographical references.

Thesis (MScEng)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: A secure product entitlement system allows one party, such as a pay-TV operator, to broadcast the same collection of information to several receiving parties while only allowing a certain subset of the receiving parties to access the information. This system must still be secure in the scenario where all receiving parties who are not allowed access to the information, pool their resources in an attempt to gain access to the information. Such a product entitlement system must also be bandwidth e cient since it can be deployed in networks where bandwidth is at a premium. The foundations of modern encryption techniques is reviewed and a survey of existing techniques, used to secure content in broadcast environments, is studied. From this collection of techniques two were identi ed as bandwidth e cient and are discussed in more detail before being implemented. An attempt is then made to design a new secure bandwidth e cient encryption scheme for protecting content in a broadcast environment. Several iterations of the design is detailed, including the security aw which makes each design insecure. The nal design was implemented and compared in several metrics to the two previously selected bandwidth e cient schemes. A framework to test the correctness of the schemes over a network is also designed and implemented. Possible future avenues of research are identi ed with regards to creating a secure broadcast encryption scheme and improving the software solution in which to use such a scheme. / AFRIKAANSE OPSOMMING: 'n Veilige produk-aanspraak-stelsel stel een party, soos byvoorbeeld 'n betaal-TV-operateur, in staat om dieselfde versameling inligting na verskeie partye uit te saai, terwyl slegs 'n bepaalde deelversameling van die ontvangende partye toegelaat sal word om toegang tot die inligting te bekom. Hierdie stelsel moet steeds die inligting beskerm in die geval waar al die ontvangende partye wat toegang geweier word, hul hulpbronne saamsmee in 'n poging om toegang te verkry. So 'n produk-aanspraak-stelsel moet ook bandwydte doeltre end benut, aangesien dit gebruik kan word in netwerke waar bandwydte baie duur is. Die fondamente van die moderne enkripsietegnieke word hersien. 'n Opname van bestaande tegnieke wat gebruik word om inligting te beskerm in 'n uitsaai omgewing word bestudeer. Uit hierdie versameling tegnieke word twee geïdenti seer as tegnieke wat bandwydte doeltre end benut en word meer volledig bespreek voordat dit geïmplementeer word. 'n Poging word dan aangewend om 'n nuwe veilige bandwydte doeltre ende enkripsietegniek te ontwerp vir die beskerming van inligting wat uitgesaai word. Verskeie iterasies van die ontwerp word uiteengesit, met 'n bespreking van die sekuriteitsfout wat elke ontwerp onveilig maak. Die nale ontwerp is geïmplementeer en aan die hand van verskeie maatstawwe vergelyk met die twee bandwydte doeltre ende tegnieke, wat voorheen gekies is. 'n Raamwerk om die korrektheid van die tegnieke oor 'n netwerk te toets, is ook ontwerp en geïmplementeer. Moontlike toekomstige rigtings van navorsing word geïdenti seer met betrekking tot die skep van 'n veilige uitsaai enkripsietegniek en die verbetering van die sagtewareoplossing wat so 'n tegniek gebruik.

Technology has become intertwined into society daily life which is not only limited to personal life but also extending into the business world. Availability, integrity and confidentiality are critical information security factors to consider when interacting with technology. Conversely many unsuspecting users have fallen prey to cyber criminals. The majority of threats encountered could have been prevented by the victims if they had sufficient knowledge to first identify and then mitigate the threat. The use of information security awareness programs provides a platform whereby users are informed about such threats. The success of these programs is significantly reduced if the content is not transferred in the most effective method to improve understanding and result in a change of behaviour. This dissertation addresses the effectiveness of using a gaming platform within an information security awareness program. The use of games allows for the users to apply knowledge within a potential scenario as seen with pilots using flight simulators. End users who have no information security background should have a safe platform where threats can be identified and methods taught to mitigate the threats. A wide selection of security awareness frameworks exist, the most appropriate framework should be considered first. The different phases of the framework would be applied within the dissertation with the main objective to ultimately determine the effectiveness of games within security awareness programs. Data was collected during the implemented information security awareness program using quantitative instruments. These included questionnaires and a developed online game designed from the literature reviewed during the study. The analysed data highlighted the effects of extrinsic motivation on knowledge transfer and validated the positive impact of game play. / Computing / M. Tech. (Information Technology)

Notre approche dans cette thèse était d'identifier où le chiffrement complètement homomorphe (FHE) pouvait être utilisé pour le domaine des sciences informatiques et de construire une plate-forme expérimentale qui nous permette de tester des algorithmes de traitement de l'information manipulant des données chiffrées. La première partie de cette thèse est consacrée à l'état de l'art. Nous présentons d'abord les systèmes de chiffrement homomorphes conçus avant 2008, puis nous présentons ceux adressant la problématique du chiffrement complètement homomorphe. Nous décrivons plusieurs méthodes de chiffrement d'intérêt pour cette thèse et discutons de leurs implémentations FHE. Enfin, nous présentons des circuits de Yao car ils peuvent résoudre des problèmes similaires que le FHE et nous parlons brièvement du chiffrement fonctionnel (FE). La deuxième partie de cette thèse présente nos contributions. Nous commençons par expliquer comment le FHE peut être utile dans divers scénarios et décrivons plusieurs cas d'utilisation pratique identifiés au cours de la thèse. Ensuite, nous décrivons notre approche pour effectuer des calculs sur des données chiffrées à l'aide du FHE et expliquons comment nous avons pu développer une plate-forme pour l'exécution dans le domaine chiffré d'une large gamme d'algorithmes en s'appuyant seulement sur l'addition et la multiplication homomorphes. Nous détaillons ensuite notre solution pour effectuer des requêtes privées sur une base de données chiffrées en utilisant le chiffrement homomorphe. Dans un dernier chapitre, nous présentons nos résultats expérimentaux. / Our approach in this thesis was to identify where FHE could be used in computer science and to build an experimental platform that allow us to test real-life algorithm running on homomorphically-encrypted data. The first part of this thesis is dedicated to the state of the art. We first present homomorphic encryption schemes designed before 2008 and then move to the Fully Homomorphic Encryption period. We describe several schemes of interest for this thesis and discuss FHE implementations. Finally, we present Yao’s garbled circuits as they can solve similar problems as FHE and briefly talk about Functional Encryption (FE). The second part of this thesis is for our contributions to the subject. We begin by explaining how FHE can be useful in various scenarios and try to provide practical use cases that we identified during the thesis. Then, we describe our approach to perform computations on encrypted data using FHE and explain how we were able to build on just the homomorphic addition and multiplication a platform for the execution in the encrypted domain of a wide range of algorithms. We then detail our solution for performing private queries on an encrypted database using homomorphic encryption. In a final chapter, we present our experimental results.

Thesis (MTech (Information Technology))--Peninsula Technikon, 2004 / Encryption was used whenever someone wanted to send a secret message to someone. The quality of the algorithm and key combination were the factors that ensured the strength of the system. However, until there were some automation one could not use complex methods for encryption because it simply took too long to encrypt and decrypt messages (even worse for images), manually. Optical technologies have recently been employed in encryption. Compared with traditional computer and electrical systems, optical technologies offer primarily two types of benefits, namely optical systems have an inherent capability for parallel processing, that is, rapid transmission of information, and information can be hidden in any of several dimensions, such as phase or spatial frequency. Optical systems therefore have an excellent capability for encoding information. In this project an image encryption technique was developed using exclusive-OR (XOR) operations in the optical domain before the captured image entered a digital computer network for further processing. A gray-level image of the object to be encrypted was converted a binary format and a pixel by pixel exclusive OR operation was performed on it with a random key-bit by making use of polarization encoding in LCD technology, before the encrypted binary image was detected by a CCD. The image may also be used as an input to a computer for comparison with a database. However, noise alters the encrypted bit and the value of the noisy encrypted bit is no longer binary. In this research the encryption techniques was evaluated and tested for applicability to encrypt and decrypt successfully. The noise performance was tested and compared. The technique was applied for image transmission over a wireless IP broadband link. Images (optical and thermal) captured from telemedicine application was transmitted and decrypted with reasonable success in this application.