Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Computer Sciences

Dissertations, Theses, and Masters Projects

Theses/Dissertations

2010

Articles 1 - 9 of 9

Full-Text Articles in Physical Sciences and Mathematics

Towards Secure Message Systems, Mengjun Xie Jan 2010

Towards Secure Message Systems, Mengjun Xie

Dissertations, Theses, and Masters Projects

Message systems, which transfer information from sender to recipient via communication networks, are indispensable to our modern society. The enormous user base of message systems and their critical role in information delivery make it the top priority to secure message systems. This dissertation focuses on securing the two most representative and dominant messages systems---e-mail and instant messaging (IM)---from two complementary aspects: defending against unwanted messages and ensuring reliable delivery of wanted messages.;To curtail unwanted messages and protect e-mail and instant messaging users, this dissertation proposes two mechanisms DBSpam and HoneyIM, which can effectively thwart e-mail spam laundering and foil malicious …


Building Efficient Wireless Infrastructures For Pervasive Computing Environments, Bo Sheng Jan 2010

Building Efficient Wireless Infrastructures For Pervasive Computing Environments, Bo Sheng

Dissertations, Theses, and Masters Projects

Pervasive computing is an emerging concept that thoroughly brings computing devices and the consequent technology into people's daily life and activities. Most of these computing devices are very small, sometimes even "invisible", and often embedded into the objects surrounding people. In addition, these devices usually are not isolated, but networked with each other through wireless channels so that people can easily control and access them. In the architecture of pervasive computing systems, these small and networked computing devices form a wireless infrastructure layer to support various functionalities in the upper application layer.;In practical applications, the wireless infrastructure often plays a …


An Interoperable And Secure Architecture For Internet-Scale Decentralized Personal Communication, David Alan Bryan Jan 2010

An Interoperable And Secure Architecture For Internet-Scale Decentralized Personal Communication, David Alan Bryan

Dissertations, Theses, and Masters Projects

Interpersonal network communications, including Voice over IP (VoIP) and Instant Messaging (IM), are increasingly popular communications tools. However, systems to date have generally adopted a client-server model, requiring complex centralized infrastructure, or have not adhered to any VoIP or IM standard. Many deployment scenarios either require no central equipment, or due to unique properties of the deployment, are limited or rendered unattractive by central servers. to address these scenarios, we present a solution based on the Session Initiation Protocol (SIP) standard, utilizing a decentralized Peer-to-Peer (P2P) mechanism to distribute data. Our new approach, P2PSIP, enables users to communicate with minimal …


Adaptive Learning And Cryptography, David Goldenberg Jan 2010

Adaptive Learning And Cryptography, David Goldenberg

Dissertations, Theses, and Masters Projects

Significant links exist between cryptography and computational learning theory. Cryptographic functions are the usual method of demonstrating significant intractability results in computational learning theory as they can demonstrate that certain problems are hard in a representation independent sense. On the other hand, hard learning problems have been used to create efficient cryptographic protocols such as authentication schemes, pseudo-random permutations and functions, and even public key encryption schemes.;Learning theory / coding theory also impacts cryptography in that it enables cryptographic primitives to deal with the issues of noise or bias in their inputs. Several different constructions of "fuzzy" primitives exist, a …


Application Of Information Theory And Statistical Learning To Anomaly Detection, Steven Gianvecchio Jan 2010

Application Of Information Theory And Statistical Learning To Anomaly Detection, Steven Gianvecchio

Dissertations, Theses, and Masters Projects

In today's highly networked world, computer intrusions and other attacks area constant threat. The detection of such attacks, especially attacks that are new or previously unknown, is important to secure networks and computers. A major focus of current research efforts in this area is on anomaly detection.;In this dissertation, we explore applications of information theory and statistical learning to anomaly detection. Specifically, we look at two difficult detection problems in network and system security, (1) detecting covert channels, and (2) determining if a user is a human or bot. We link both of these problems to entropy, a measure of …


Supporting Feature-Level Software Maintenance, Meghan Kathleen Revelle Jan 2010

Supporting Feature-Level Software Maintenance, Meghan Kathleen Revelle

Dissertations, Theses, and Masters Projects

Software maintenance is the process of modifying a software system to fix defects, improve performance, add new functionality, or adapt the system to a new environment. A maintenance task is often initiated by a bug report or a request for new functionality. Bug reports typically describe problems with incorrect behaviors or functionalities. These behaviors or functionalities are known as features. Even in very well-designed systems, the source code that implements features is often not completely modularized. The delocalized nature of features makes maintaining them challenging. Since maintenance tasks are expressed in terms of features, the goal of this dissertation is …


Secure And Efficient Data Extraction For Ubiquitous Computing Applications, Chiu Chiang Tan Jan 2010

Secure And Efficient Data Extraction For Ubiquitous Computing Applications, Chiu Chiang Tan

Dissertations, Theses, and Masters Projects

Ubiquitous computing creates a world where computers have blended seamlessly into our physical environment. In this world, a "computer" is no longer a monitor-and-keyboard setup, but everyday objects such as our clothing and furniture. Unlike current computer systems, most ubiquitous computing systems are built using small, embedded devices with limited computational, storage and communication abilities. A common requirement for many ubiquitous computing applications is to utilize the data from these small devices to perform more complex tasks. For critical applications such as healthcare or medical related applications, there is a need to ensure that only authorized users have timely access …


Enhancing Web Browsing Security, Chuan Yue Jan 2010

Enhancing Web Browsing Security, Chuan Yue

Dissertations, Theses, and Masters Projects

Web browsing has become an integral part of our lives, and we use browsers to perform many important activities almost everyday and everywhere. However, due to the vulnerabilities in Web browsers and Web applications and also due to Web users' lack of security knowledge, browser-based attacks are rampant over the Internet and have caused substantial damage to both Web users and service providers. Enhancing Web browsing security is therefore of great need and importance.;This dissertation concentrates on enhancing the Web browsing security through exploring and experimenting with new approaches and software systems. Specifically, we have systematically studied four challenging Web …


Multimodal Non-Rigid Registration For Image-Guided Head And Neck Surgery, Michael Lawrence Weissberger Jan 2010

Multimodal Non-Rigid Registration For Image-Guided Head And Neck Surgery, Michael Lawrence Weissberger

Dissertations, Theses, and Masters Projects

No abstract provided.