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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
321

MODERN CRYPTOGRAPHY

Lopez, Samuel 01 June 2018 (has links)
We live in an age where we willingly provide our social security number, credit card information, home address and countless other sensitive information over the Internet. Whether you are buying a phone case from Amazon, sending in an on-line job application, or logging into your on-line bank account, you trust that the sensitive data you enter is secure. As our technology and computing power become more sophisticated, so do the tools used by potential hackers to our information. In this paper, the underlying mathematics within ciphers will be looked at to understand the security of modern ciphers. An extremely important algorithm in today's practice is the Advanced Encryption Standard (AES), which is used by our very own National Security Agency (NSA) for data up to TOP SECRET. Another frequently used cipher is the RSA cryptosystem. Its security is based on the concept of prime factorization, and the fact that it is a hard problem to prime factorize huge numbers, numbers on the scale of 2^{2048} or larger. Cryptanalysis, the study of breaking ciphers, will also be studied in this paper. Understanding effective attacks leads to understanding the construction of these very secure ciphers.
322

Novel Cryptographic Primitives and Protocols for Censorship Resistance

Dyer, Kevin Patrick 24 July 2015 (has links)
Internet users rely on the availability of websites and digital services to engage in political discussions, report on newsworthy events in real-time, watch videos, etc. However, sometimes those who control networks, such as governments, censor certain websites, block specific applications or throttle encrypted traffic. Understandably, when users are faced with egregious censorship, where certain websites or applications are banned, they seek reliable and efficient means to circumvent such blocks. This tension is evident in countries such as a Iran and China, where the Internet censorship infrastructure is pervasive and continues to increase in scope and effectiveness. An arms race is unfolding with two competing threads of research: (1) network operators' ability to classify traffic and subsequently enforce policies and (2) network users' ability to control how network operators classify their traffic. Our goal is to understand and progress the state-of-the-art for both sides. First, we present novel traffic analysis attacks against encrypted communications. We show that state-of-the-art cryptographic protocols leak private information about users' communications, such as the websites they visit, applications they use, or languages used for communications. Then, we investigate means to mitigate these privacy-compromising attacks. Towards this, we present a toolkit of cryptographic primitives and protocols that simultaneously (1) achieve traditional notions of cryptographic security, and (2) enable users to conceal information about their communications, such as the protocols used or websites visited. We demonstrate the utility of these primitives and protocols in a variety of real-world settings. As a primary use case, we show that these new primitives and protocols protect network communications and bypass policies of state-of-the-art hardware-based and software-based network monitoring devices.
323

Examining the Behavioral Intention of Individuals' Compliance with Information Security Policies

Brown, David A. 01 January 2017 (has links)
Target Corporation experienced an information security breach resulting in compromising customers' financial information. Management is responsible for implementing adequate information security policies that protect corporate data and minimize financial losses. The purpose of this experimental study was to examine the effect of a fear appeal communication on an individual's information security policy behavioral intention. The sample population involved information technology professionals randomly selected from the SurveyMonkey audience. A research model, developed using constructs from deterrence theory and protection motivation theory, became the structural model used for partial least squares-structural equation modeling (PLS-SEM) analysis of the survey response data, which indicated that self-efficacy was statistically significant. The remaining model variables, perceived threat vulnerability, perceived threat severity, response efficacy, informal sanction certainty, informal sanction severity, formal sanction certainty, and formal sanction severity, were not statistically significant. A statistically significant self-efficacy result could indicate confidence among the population to comply with information security policies. The nonsignificant results could indicate the fear appeal treatment did not motivate a change in behavior or information security policy awareness bias was introduced by selecting information technology professionals. Social change in information security could be achieved by developing an effective information security policy compliance fear appeal communication, which could change information security compliance behavior and contribute to securing the nation's critical cyber infrastructure and protecting data.
324

Exploring the Cybersecurity Hiring Gap

Pierce, Adam O. 01 January 2016 (has links)
Cybersecurity is one of the fastest growing segments of information technology. The Commonwealth of Virginia has 30,000 cyber-related jobs open because of the lack of skilled candidates. The study is necessary because some business managers lack strategies for hiring cybersecurity professionals for U.S. Department of Defense (DoD) contracts. The purpose of this case study was to explore strategies business managers in DoD contracting companies used to fill cybersecurity positions. The conceptual framework used for this study was the organizational learning theory. A purposeful sample of 8 successful business managers with cybersecurity responsibilities working for U.S. DoD contracting companies that successfully hired cybersecurity professionals in Hampton Roads, VA participated in the study. Data collection included semistructured interviews and a review of job postings from the companies represented by the participants. Coding, content, and thematic analysis were the methods used to analyze data. Within-methods triangulation was used to add accuracy to the analysis. At the conclusion of the data analysis, two main themes emerged: maintaining contractual requirements and a strong recruiting process. Contractual requirements guided how hiring managers hired cybersecurity personnel and executed the contract. A strong hiring process added efficiency to the hiring process. The findings of the study may contribute to positive social change by encouraging the recruitment and retention of cybersecurity professionals. Skilled cybersecurity professionals may safeguard businesses and society from Internet crime, thereby encouraging the safe exchange and containment of data.
325

An overview of Product Service System through Integrated Vehicle Health Management in an information sensitive industry

Ehlin, Max January 2019 (has links)
Purpose – The research purpose is to enhance knowledge of how organizations can form a PSS through an IVHM system when information is sensitive. Method – A single case study design of abductive approach was used, with data collection through six semi-structured interviews. Findings – A system combining IVHM and PSS has many potential benefits, however there are several challenges that need to be overcome in order to implementing a successful model. Theoretical implications – This study treads a new area not previously explored in the literature when it combines PSS and IVHM, which relies heavily on information flow to succeed, with a case of information sensitivity. This study hence explores a problematic area for either PSS or IVHM, expanding the current literature and providing initial suggestions of how to navigate this. Practical implications – Firstly, it shows managers the challenges that comes with implementing PSS-IVHM and increasing involvement in the customers’ processes. Secondly, this study shows the theoretical and general challenges of PSS-IVHM and applies the case study’s perspective of information management, granting managers a larger foundation of knowledge before starting their initiatives of PSS-IVHM. Limitations and future research – This study provides a limited amount of empirical data. Therefore, future research should focus on increasing and widening data collection. The study suggests there is a considerable challenge in conservatism within the defence industry and therefore future research is suggested to explore how change management can combat this challenge.
326

Modeling and Pattern Matching Security Properties with Dependence Graphs

Fåk, Pia January 2005 (has links)
<p>With an increasing number of computers connected to the Internet, the number of malicious attacks on computer systems also raises. The key to all successful attacks on information systems is finding a weak spot in the victim system. Some types of bugs in software can constitute such weak spots. This thesis presents and evaluates a technique for statically detecting such security related bugs. It models the analyzed program as well as different types of security bugs with dependence graphs. Errors are detected by searching the program graph model for subgraphs matching security bug models.</p><p>The technique has been implemented in a prototype tool called GraphMatch. Its accuracy and performance have been measured by analyzing open source application code for missing input validation vulnerabilities. The test results show that the accuracy obtained so far is low and the complexity of the algorithms currently used cause analysis times of several hours even for fairly small projects. Further research is needed to determine if the performance and accuracy can be improved.</p>
327

Usable Security Policies for Runtime Environments

Herzog, Almut January 2007 (has links)
The runtime environments provided by application-level virtual machines such as the Java Virtual Machine or the .NET Common Language Runtime are attractive for Internet application providers because the applications can be deployed on any platform that supports the target virtual machine. With Internet applications, organisations as well as end users face the risk of viruses, trojans, and denial of service attacks. Virtual machine providers are aware of these Internet security risks and provide, for example, runtime monitoring of untrusted code and access control to sensitive resources. Our work addresses two important security issues in runtime environments. The first issue concerns resource or release control. While many virtual machines provide runtime access control to resources, they do not provide any means of limiting the use of a resource once access is granted; they do not provide so-called resource control. We have addressed the issue of resource control in the example of the Java Virtual Machine. In contrast to others’ work, our solution builds on an enhancement to the existing security architecture. We demonstrate that resource control permissions for Java-mediated resources can be integrated into the regular Java security architecture, thus leading to a clean design and a single external security policy. The second issue that we address is the usabilityhttps://www.diva-portal.org/liu/webform/form.jsp DiVA Web Form and security of the setup of security policies for runtime environments. Access control decisions are based on external configuration files, the security policy, which must be set up by the end user. This set-up is security-critical but also complicated and errorprone for a lay end user and supportive, usable tools are so far missing. After one of our usability studies signalled that offline editing of the configuration file is inefficient and difficult for end users, we conducted a usability study of personal firewalls to identify usable ways of setting up a security policy at runtime. An analysis of general user help techniques together with the results from the two previous studies resulted in a proposal of design guidelines for applications that need to set up a security policy. Our guidelines have been used for the design and implementation of the tool JPerM that sets the Java security policy at runtime. JPerM evaluated positively in a usability study and supports the validity of our design guidelines.
328

Assessment of Enterprise Information Security : How to make it Credible and Efficient

Johansson, Erik January 2005 (has links)
Information is an important business asset in today’s enterprises. Hence enterprise information security is an important system quality that must be carefully managed. Although enterprise information security is acknowledged as one of the most central areas for enterprise IT management, the topic still lacks adequate support for decision making on top-management level. This composite thesis consists of four articles which presents the Enterprise Information Security Assessment Method (EISAM), a comprehensive method for assessing the current state of the enterprise information security. The method is useful in helping guide top-management’s decision-making because of the following reasons: 1) it is easy to understand, 2) it is prescriptive, 3) it is credible, and 4) it is efficient. The assessment result is easy to understand because it presents a quantitative estimate. The result can be presented as an aggregated single value, abstracting the details of the assessment. The result is easy to grasp and enables comparisons both within the organization and in terms of industry in general. The method is prescriptive since it delivers concrete and traceable measurements. This helps guide top-level management in their decisions regarding enterprise-wide information security by highlighting the areas where improvements efforts are essential. It is credible for two reasons. Firstly, the method presents an explicit and transparent definition of enterprise information security. Secondly, the method in itself includes an indication of assessment uncertainty, expressed in terms of confidence levels. The method is efficient because it focuses on important enterprise information security aspects, and because it takes into account how difficult it is to find security related evidence. Being resource sparse it enables assessments to take place regularly, which gives valuable knowledge for long-term decision-making. The usefulness of the presented method, along with its development, has been verified through empirical studies at a leading electric power company in Europe and through statistical surveys carried out among information security experts in Sweden. The success from this research should encourage further researcher in using these analysis techniques to guide decisions on other enterprise architecture attributes. / QC 20101028
329

Investigating the Relationship between IT and Organizations: A Research Trilogy

Raymond, Benoit 12 December 2010 (has links)
The overall objective of this dissertation is to contribute to knowledge and theory about the influence of information technology (IT) on organizations and their members. This dissertation is composed of three related studies, each examining different aspects of the relationship between IT and organizations. The objective of the first study is to provide an overview of the dominant theoretical perspectives that IS researchers have used in the last five decades to study the influence of technology on organizations and their members. Without being exhaustive, this study seeks more specifically to identify, for each decade, the dominant theoretical perspectives used in the IS field. These dominant theoretical perspectives are illustrated by the selection and description of exemplars published in the decade and their implications for researchers and practitioners are discussed. This review is useful not only for understanding past trends and the current state of research in this area but also to foresee its future directions and guide researchers in their future research on the influence of IT on organizations and their members. The objective of the second study is to theorize how IT artifacts influence the design and performance of organizational routines. This study adopts organizational routines theory as its theoretical lens. Organizational routines represent an important part of almost every organization and organizational routines theory is an influential theory that explains how the accomplishment of organizational routines can contribute to both organizational stability and change. However, the current form of this theory has several limitations such as its neglect of the material aspect of artifacts and the distinctive characteristics of IT artifacts, and its treatment of artifacts as outside of organizational routines. This study seeks to overcome these limitations by extending organizational routines theory. The objective of the third study is to develop a better understanding of information security standards by analyzing the structure, nature and content of their controls. This study investigates also the mechanisms used in the design of information security standards to make them both applicable to a wide range of organizations and adaptable to various specific organizational settings. The results of this study led to the proposition of a new theory for information systems called generative control theory.
330

Security and Privacy Preservation in Mobile Social Networks

Liang, Xiaohui January 2013 (has links)
Social networking extending the social circle of people has already become an important integral part of our daily lives. As reported by ComScore, social networking sites such as Facebook and Twitter have reached 82 percent of the world's online population, representing 1.2 billion users around the world. In the meantime, fueled by the dramatic advancements of smartphones and the ubiquitous connections of Bluetooth/WiFi/3G/LTE networks, social networking further becomes available for mobile users and keeps them posted on the up-to-date worldwide news and messages from their friends and families anytime anywhere. The convergence of social networking, advanced smartphones, and stable network infrastructures brings us a pervasive and omnipotent communication platform, named mobile social network (MSN), helping us stay connected better than ever. In the MSN, multiple communication techniques help users to launch a variety of applications in multiple communication domains including single-user domain, two-user domain, user-chain domain, and user-star domain. Within different communication domains, promising mobile applications are fostered. For example, nearby friend search application can be launched in the two-user or user-chain domains to help a user find other physically-close peers who have similar interests and preferences; local service providers disseminate advertising information to nearby users in the user-star domain; and health monitoring enables users to check the physiological signals in the single-user domain. Despite the tremendous benefits brought by the MSN, it still faces many technique challenges among of which security and privacy protections are the most important ones as smartphones are vulnerable to security attacks, users easily neglect their privacy preservation, and mutual trust relationships are difficult to be established in the MSN. In this thesis, we explore the unique characteristics and study typical research issues of the MSN. We conduct our research with a focus on security and privacy preservation while considering human factors. Specifically, we consider the profile matching application in the two-user domain, the cooperative data forwarding in the user-chain domain, the trustworthy service evaluation application in the user-star domain, and the healthcare monitoring application in the single-user domain. The main contributions are, i) considering the human comparison behavior and privacy requirements, we first propose a novel family of comparison-based privacy-preserving profile matching (PPM) protocols. The proposed protocols enable two users to obtain comparison results of attribute values in their profiles, while the attribute values are not disclosed. Taking user anonymity requirement as an evaluation metric, we analyze the anonymity protection of the proposed protocols. From the analysis, we found that the more comparison results are disclosed, the less anonymity protection is achieved by the protocol. Further, we explore the pseudonym strategy and an anonymity enhancing technique where users could be self-aware of the anonymity risk level and take appropriate actions when needed; ii) considering the inherent MSN nature --- opportunistic networking, we propose a cooperative privacy-preserving data forwarding (PDF) protocol to help users forward data to other users. We indicate that privacy and effective data forwarding are two conflicting goals: the cooperative data forwarding could be severely interrupted or even disabled when the privacy preservation of users is applied, because without sharing personal information users become unrecognizable to each other and the social interactions are no longer traceable. We explore the morality model of users from classic social theory, and use game-theoretic approach to obtain the optimal data forwarding strategy. Through simulation results, we show that the proposed cooperative data strategy can achieve both the privacy preservation and the forwarding efficiency; iii) to establish the trust relationship in a distributed MSN is a challenging task. We propose a trustworthy service evaluation (TSE) system, to help users exchange their service reviews toward local vendors. However, vendors and users could be the potential attackers aiming to disrupt the TSE system. We then consider the review attacks, i.e., vendors rejecting and modifying the authentic reviews of users, and the Sybil attacks, i.e., users abusing their pseudonyms to generate fake reviews. To prevent these attacks, we explore the token technique, the aggregate signature, and the secret sharing techniques. Simulation results show the security and the effectiveness of the TSE system can be guaranteed; iv) to improve the efficiency and reliability of communications in the single-user domain, we propose a prediction-based secure and reliable routing framework (PSR). It can be integrated with any specific routing protocol to improve the latter's reliability and prevent data injection attacks during data communication. We show that the regularity of body gesture can be learned and applied by body sensors such that the route with the highest predicted link quality can always be chose for data forwarding. The security analysis and simulation results show that the PSR significantly increases routing efficiency and reliability with or without the data injection attacks.

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