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Full-Text Articles in Computer Sciences

Magnesium Object Manager Sandbox, A More Effective Sandbox Method For Windows 7, Martin A. Gilligan Mar 2012

Magnesium Object Manager Sandbox, A More Effective Sandbox Method For Windows 7, Martin A. Gilligan

Theses and Dissertations

A major issue in computer security is limiting the affects a program can have on a computer. One way is to place the program into a sandbox, a limited environment. Many attempts have been made to create a sandbox that maintains the usability of a program and effectively limits the effects of the program. Sandboxes that limit the resources programs can access, have succeeded. To test the effectiveness of a sandbox that limits the resources a program can access on Windows 7, the Magnesium Object Manager Sandbox (MOMS) is created. MOMS uses a kernel mode Windows component to monitor and …


Scalable Wavelet-Based Active Network Stepping Stone Detection, Joseph I. Gilbert Mar 2012

Scalable Wavelet-Based Active Network Stepping Stone Detection, Joseph I. Gilbert

Theses and Dissertations

Network intrusions leverage vulnerable hosts as stepping stones to penetrate deeper into a network and mask malicious actions from detection. This research focuses on a novel active watermark technique using Discrete Wavelet Transformations to mark and detect interactive network sessions. This technique is scalable, nearly invisible and resilient to multi-flow attacks. The watermark is simulated using extracted timestamps from the CAIDA 2009 dataset and replicated in a live environment. The simulation results demonstrate that the technique accurately detects the presence of a watermark at a 5% False Positive and False Negative rate for both the extracted timestamps as well as …


An Analysis Of Error Reconciliation Protocols For Use In Quantum Key Distribution, James S. Johnson Mar 2012

An Analysis Of Error Reconciliation Protocols For Use In Quantum Key Distribution, James S. Johnson

Theses and Dissertations

Quantum Key Distribution (QKD) is a method for transmitting a cryptographic key between a sender and receiver in a theoretically unconditionally secure way. Unfortunately, the present state of technology prohibits the flawless quantum transmission required to make QKD a reality. For this reason, error reconciliation protocols have been developed which preserve security while allowing a sender and receiver to reconcile the errors in their respective keys. The most famous of these protocols is Brassard and Salvail's Cascade, which is effective, but suffers from a high communication complexity and therefore results in low throughput. Another popular option is Buttler's Winnow protocol, …


Evaluation Of Malware Target Recognition Deployed In A Cloud-Based Fileserver Environment, G. Parks Masters Mar 2012

Evaluation Of Malware Target Recognition Deployed In A Cloud-Based Fileserver Environment, G. Parks Masters

Theses and Dissertations

Cloud computing, or the migration of computing resources from the end user to remotely managed locations where they can be purchased on-demand, presents several new and unique security challenges. One of these challenges is how to efficiently detect malware amongst files that are possibly spread across multiple locations in the Internet over congested network connections. This research studies how such an environment will impact the performance of malware detection. A simplified cloud environment is created in which network conditions are fully controlled. This environment includes a fileserver, a detection server, the detection mechanism, and clean and malicious file sample sets. …


Evaluation Of Traditional Security Solutions In The Scada Environment, Robert D. Larkin Mar 2012

Evaluation Of Traditional Security Solutions In The Scada Environment, Robert D. Larkin

Theses and Dissertations

Supervisory Control and Data Acquisition (SCADA) systems control and monitor the electric power grid, water treatment facilities, oil and gas pipelines, railways, and other Critical Infrastructure (CI). In recent years, organizations that own and operate these systems have increasingly interconnected them with their enterprise network to take advantage of cost savings and operational benefits. This trend, however, has introduced myriad vulnerabilities associated with the networking environment. As a result, the once isolated systems are now susceptible to a wide range of threats that previously did not exist. To help address the associated risks, security professionals seek to incorporate mitigation solutions …


Security Verification Of Secure Manet Routing Protocols, Matthew F. Steele Mar 2012

Security Verification Of Secure Manet Routing Protocols, Matthew F. Steele

Theses and Dissertations

Secure mobile ad hoc network (MANET) routing protocols are not tested thoroughly against their security properties. Previous research focuses on verifying secure, reactive, accumulation-based routing protocols. An improved methodology and framework for secure MANET routing protocol verification is proposed which includes table-based and proactive protocols. The model checker, SPIN, is selected as the core of the secure MANET verification framework. Security is defined by both accuracy and availability: a protocol forms accurate routes and these routes are always accurate. The framework enables exhaustive verification of protocols and results in a counter-example if the protocol is deemed insecure. The framework is …


A Black Hole Attack Model For Reactive Ad-Hoc Protocols, Christopher W. Badenhop Mar 2012

A Black Hole Attack Model For Reactive Ad-Hoc Protocols, Christopher W. Badenhop

Theses and Dissertations

Net-Centric Warfare places the network in the center of all operations, making it a critical resource to attack and defend during wartime. This thesis examines one particular network attack, the Black Hole attack, to determine if an analytical model can be used to predict the impact of this attack on ad-hoc networks. An analytical Black Hole attack model is developed for reactive ad-hoc network protocols DSR and AODV. To simplify topology analysis, a hypercube topology is used to approximate ad-hoc topologies that have the same average node degree. An experiment is conducted to compare the predicted results of the analytical …


Empirical Analysis Of Optical Attenuator Performance In Quantum Key Distribution Systems Using A Particle Model, Thomas C. Adams Mar 2012

Empirical Analysis Of Optical Attenuator Performance In Quantum Key Distribution Systems Using A Particle Model, Thomas C. Adams

Theses and Dissertations

Quantum key distribution networks currently represent an active area of development and software modeling to address the security of future communications. One of the components used in quantum key distribution implementations is an optical attenuator. Its role in the system is necessary to reach the single photon per bit necessary to maintain theoretically perfect secrecy. How the photon pulse is modeled has a significant impact on the accuracy and performance of quantum channel components like the optical attenuator. Classical physics describe light using Maxwell's wave equations for electromagnetism. Quantum physics has demonstrated light also behaves as discrete particles referred to …


Context Aware Routing Management Architecture For Airborne Networks, Joan A. Betances Mar 2012

Context Aware Routing Management Architecture For Airborne Networks, Joan A. Betances

Theses and Dissertations

This thesis advocates the use of Kalman filters in conjunction with network topology information derived from the Air Tasking Order (ATO) during the planning phase for military missions. This approach is the basis for an algorithm that implements network controls that optimize network performance for Mobile Ad hoc Networks (MANET). The trajectories of relevant nodes (airborne platforms) participating in the MANET can be forecasted by parsing key information contained in the ATO. This information is used to develop optimum network routes that can significantly improve MANET performance. Improved MANET performance in the battlefield enables decision makers to access information from …


Detector Design Considerations In High-Dimensional Artificial Immune Systems, Jason M. Bindewald Mar 2012

Detector Design Considerations In High-Dimensional Artificial Immune Systems, Jason M. Bindewald

Theses and Dissertations

This research lays the groundwork for a network intrusion detection system that can operate with only knowledge of normal network traffic, using a process known as anomaly detection. Real-valued negative selection (RNS) is a specific anomaly detection algorithm that can be used to perform two-class classification when only one class is available for training. Researchers have shown fundamental problems with the most common detector shape, hyperspheres, in high-dimensional space. The research contained herein shows that the second most common detector type, hypercubes, can also cause problems due to biasing certain features in high dimensions. To address these problems, a new …


Understanding How Reverse Engineers Make Sense Of Programs From Assembly Language Representations, Adam R. Bryant Mar 2012

Understanding How Reverse Engineers Make Sense Of Programs From Assembly Language Representations, Adam R. Bryant

Theses and Dissertations

This dissertation develops a theory of the conceptual and procedural aspects involved with how reverse engineers make sense of executable programs. Software reverse engineering is a complex set of tasks which require a person to understand the structure and functionality of a program from its assembly language representation, typically without having access to the program's source code. This dissertation describes the reverse engineering process as a type of sensemaking, in which a person combines reasoning and information foraging behaviors to develop a mental model of the program. The structure of knowledge elements used in making sense of executable programs are …


Towards Quantifying Programmable Logic Controller Resilience Against Intentional Exploits, Henry W. Bushey Mar 2012

Towards Quantifying Programmable Logic Controller Resilience Against Intentional Exploits, Henry W. Bushey

Theses and Dissertations

Supervisory Control and Data Acquisition (SCADA) systems control and monitor services for the nation's critical infrastructure. Recent cyber induced events (e.g., Stuxnet) provide an example of a targeted, covert cyber attack against a SCADA system that resulted in physical effects. Of particular note is how Stuxnet exploited the trust relationship between the human machine interface (HMI) and programmable logic controllers (PLCs). Current methods for validating system operating parameters rely on message exchange and network communications protocols, generally observed at the HMI. Although sufficient at the macro level, this method does not provide detection of malware that exhibits physical effects via …


Obfuscating Against Side-Channel Power Analysis Using Hiding Techniques For Aes, Austin W. Fritzke Mar 2012

Obfuscating Against Side-Channel Power Analysis Using Hiding Techniques For Aes, Austin W. Fritzke

Theses and Dissertations

The transfer of information has always been an integral part of military and civilian operations, and remains so today. Because not all information we share is public, it is important to secure our data from unwanted parties. Message encryption serves to prevent all but the sender and recipient from viewing any encrypted information as long as the key stays hidden. The Advanced Encryption Standard (AES) is the current industry and military standard for symmetric-key encryption. While AES remains computationally infeasible to break the encrypted message stream, it is susceptible to side-channel attacks if an adversary has access to the appropriate …


Binary Disassembly Block Coverage By Symbolic Execution Vs. Recursive Descent, Jonathan D. Miller Mar 2012

Binary Disassembly Block Coverage By Symbolic Execution Vs. Recursive Descent, Jonathan D. Miller

Theses and Dissertations

This research determines how appropriate symbolic execution is (given its current implementation) for binary analysis by measuring how much of an executable symbolic execution allows an analyst to reason about. Using the S2E Selective Symbolic Execution Engine with a built-in constraint solver (KLEE), this research measures the effectiveness of S2E on a sample of 27 Debian Linux binaries as compared to a traditional static disassembly tool, IDA Pro. Disassembly code coverage and path exploration is used as a metric for determining success. This research also explores the effectiveness of symbolic execution on packed or obfuscated samples of the same binaries …


Mfire-2: A Multi Agent System For Flow-Based Intrusion Detection Using Stochastic Search, Timothy J. Wilson Mar 2012

Mfire-2: A Multi Agent System For Flow-Based Intrusion Detection Using Stochastic Search, Timothy J. Wilson

Theses and Dissertations

Detecting attacks targeted against military and commercial computer networks is a crucial element in the domain of cyberwarfare. The traditional method of signature-based intrusion detection is a primary mechanism to alert administrators to malicious activity. However, signature-based methods are not capable of detecting new or novel attacks. This research continues the development of a novel simulated, multiagent, flow-based intrusion detection system called MFIRE. Agents in the network are trained to recognize common attacks, and they share data with other agents to improve the overall effectiveness of the system. A Support Vector Machine (SVM) is the primary classifier with which agents …


Improving Filtering Of Email Phishing Attacks By Using Three-Way Text Classifiers, Alberto Trevino Mar 2012

Improving Filtering Of Email Phishing Attacks By Using Three-Way Text Classifiers, Alberto Trevino

Theses and Dissertations

The Internet has been plagued with endless spam for over 15 years. However, in the last five years spam has morphed from an annoying advertising tool to a social engineering attack vector. Much of today's unwanted email tries to deceive users into replying with passwords, bank account information, or to visit malicious sites which steal login credentials and spread malware. These email-based attacks are known as phishing attacks. Much has been published about these attacks which try to appear real not only to users and subsequently, spam filters. Several sources indicate traditional content filters have a hard time detecting phishing …


Infinitesimal Perturbation Analysis For The Capacitated Finite-Horizon Multi-Period Multiproduct Newsvendor Problem, Brigham Bond Wilson Mar 2012

Infinitesimal Perturbation Analysis For The Capacitated Finite-Horizon Multi-Period Multiproduct Newsvendor Problem, Brigham Bond Wilson

Theses and Dissertations

An optimal ordering scheme for the capacitated, finite-horizon, multi-period, multiproduct newsvendor problem was proposed by cite {shao06} using a hedging point policy. This solution requires the calculation of a central curve that divides the different ordering regions and a vector that defines the target inventory levels. The central curve is a nonlinear curve that determines the optimal order quantities as a function of the initial inventory levels. In this paper we propose a method for calculating this curve and vector using spline functions, infinitesimal perturbation analysis (IPA), and convex optimization. Using IPA the derivatives of the cost with respect to …


Feasibility Of Tcp For Wireless Mesh Networks, Richard Lloyd Lee Mar 2012

Feasibility Of Tcp For Wireless Mesh Networks, Richard Lloyd Lee

Theses and Dissertations

When used in a wireless mesh network, TCP has shortcomings in the areas of throughput and fairness among traffic flows. Several methods have been proposed to deal with TCP's weakness in a wireless mesh, but most have been evaluated with simulations rather than experimentally. We evaluate several major enhancements to TCP – pacing, conservative windows, and delayed ACKs – to determine whether they improve performance or fairness in a mesh network operating in the BYU Computer Science building. We also draw conclusions about the effectiveness of wireless network simulators based on the accuracy of reported simulation results.


Analysis And Characterization Of Author Contribution Patterns In Open Source Software Development, Quinn Carlson Taylor Mar 2012

Analysis And Characterization Of Author Contribution Patterns In Open Source Software Development, Quinn Carlson Taylor

Theses and Dissertations

Software development is a process fraught with unpredictability, in part because software is created by people. Human interactions add complexity to development processes, and collaborative development can become a liability if not properly understood and managed. Recent years have seen an increase in the use of data mining techniques on publicly-available repository data with the goal of improving software development processes, and by extension, software quality. In this thesis, we introduce the concept of author entropy as a metric for quantifying interaction and collaboration (both within individual files and across projects), present results from two empirical observational studies of open-source …


Using Agent-Based Models To Understand Multi-Operator Supervisory Control, Yisong Guo Mar 2012

Using Agent-Based Models To Understand Multi-Operator Supervisory Control, Yisong Guo

Theses and Dissertations

As technology advances, many practical applications require human-controlled robots. For such applications, it is useful to determine the optimal number of robots an operator should control to maximize human efficiency given different situations. One way to achieve this is through computer simulations of team performance. In order to factor in various parameters that may affect team performance, an agent-based model will be used. Agent-based modeling is a computational method that enables a researcher to create, analyze, and experiment with models composed of agents that interact within an environment [12]. We construct an agent-based model of humans interacting with robots, and …


3-D Scene Reconstruction From Aerial Imagery, Jared M. Ekholm Mar 2012

3-D Scene Reconstruction From Aerial Imagery, Jared M. Ekholm

Theses and Dissertations

3-D scene reconstructions derived from Structure from Motion (SfM) and Multi-View Stereo (MVS) techniques were analyzed to determine the optimal reconnaissance flight characteristics suitable for target reconstruction. In support of this goal, a preliminary study of a simple 3-D geometric object facilitated the analysis of convergence angles and number of camera frames within a controlled environment. Reconstruction accuracy measurements revealed at least 3 camera frames and a 6 convergence angle were required to achieve results reminiscent of the original structure. The central investigative effort sought the applicability of certain airborne reconnaissance flight profiles to reconstructing ground targets. The data sets …


Commit Patterns And Threats To Validity In Analysis Of Open Source Software Repositories, Alexander Curtis Maclean Feb 2012

Commit Patterns And Threats To Validity In Analysis Of Open Source Software Repositories, Alexander Curtis Maclean

Theses and Dissertations

In the course of studying the effects of programming in multiple languages, we unearthed troubling trends in SourceForge artifacts. Our initial studies suggest that programming in multiple languages concurrently negatively affects developer productivity. While addressing our initial question of interest, we discovered a pattern of monolithic commits in the SourceForge community. Consequently, we also report on the effects that this pattern of commits can have when using SourceForge as a data-source for temporal analysis of open source projects or for studies of individual developers.


Integrating Information Quality In Visual Analytics, Ahmed Abuhalimeh Feb 2012

Integrating Information Quality In Visual Analytics, Ahmed Abuhalimeh

Theses and Dissertations

Visualization and visual analytics rely heavily on rapid exploration, and a combination of various information dimensions and sources performed by an analyst. Integrating Information Quality involves combining Information Quality (IQ) residing in different sources and providing users with a unified view of this data quality. This process becomes significant in a variety of situations both commercial and scientific. Integrating information appears with increasing frequency as the volume and the need to share existing information grows. This research focus on a subset of IQ dimensions, which we term subjective IQ (SIQ). Visual analytics techniques rely on fast, continuous, and interactive user …


Përparësit Dhe Mangësit E E-Mësimit Përmes Platformave Akademike Në Shkollimet E Larta Në Kosovë, Sylejman Ahmeti Feb 2012

Përparësit Dhe Mangësit E E-Mësimit Përmes Platformave Akademike Në Shkollimet E Larta Në Kosovë, Sylejman Ahmeti

Theses and Dissertations

Çka është e-Mësimi? e-Mësimi (e-Learning) është përdorimi i teknologjisë për të mundësuar që njerëzit të mësojnë në çdo kohë dhe kudo. e-Mësimi është një qasje e re e cila përmban në vete të mësuarit në njërën anë dhe teknologjinë Informative dhe kompjuterët në anën tjetër. Është shkrirje e të mësuarit dhe internetit në një vend. Duke e pare te arsyeshme se një prej zhvillimit të shoqërisë është shkollimi sa më i lartë, në ketë temë do të shfaqim një mundësi tjetër për shkollim të lart për personat të cilët nuk kanë mundësi të ndjekjes së rregullt të shkollimit të lartë …


Modeling And Simulation Of Cpu Mechanisms For Providing Operating System Support For Mobile Multimedia Systems, Abbas Khlaf Abd Al Muhsen Jan 2012

Modeling And Simulation Of Cpu Mechanisms For Providing Operating System Support For Mobile Multimedia Systems, Abbas Khlaf Abd Al Muhsen

Theses and Dissertations

In the ever-increasing digital world, mobile devices, such as smart-phones and tablet computers are on the trend to become the most used electronic devices. Multimedia applications running on these devices require appropriate operating system support. One limitation of the capabilities of these devices comes from their power source: they are all battery-powered, with a restricted battery energy budget. An important part of the total power is used by the CPU of these devices, so by controlling the power consumed by the CPU, the overall power used by the mobile device will be significantly reduced. This work proposes a systems engineering …


Visualizing Graphs With Distinguishable Edges And Ordered Binary Trees In Small Area, Andrew Fabian Jan 2012

Visualizing Graphs With Distinguishable Edges And Ordered Binary Trees In Small Area, Andrew Fabian

Theses and Dissertations

As graph layouts and visualizations have been at the forefront of graph drawing research for decades, it consequently led to aesthetic heuristics that not only generated better visualizations and aesthetically appealing graphs but also improved readability and understanding of the graphs. A variety of approaches examines aesthetics of nodes, edges, or graph layout, and related readability metrics. In this thesis, two solutions incorporating Gestalt principles to alleviate the effects of the edge crossing problem are presented. Alleviating this problem improves graph aesthetics and readability. Secondly, improving the known bounds on two aesthetic requirements (area and aspect ratio) for planar straight-line …


Modeling And Simulation, Driton Emërllahu Jan 2012

Modeling And Simulation, Driton Emërllahu

Theses and Dissertations

Hulumtimet Shkencore në lëmin e modelimit dhe simulimit kanë filluar dhe vazhdojnë thuajse tash e 30 vite. Fondamental është fakti se objektivë kryesore e përdorimit të modelimit dhe simulimit është mbështetja për të marrë një vendim sa më të mirë. Teknologjia e avancuar ditëve të sotme ka ushtruar një ndikim të madh të shtrirjes së përdorimit të modelimit po thuajse në të gjitha fushat shkencore dhe shoqërore. Sot modelimi dhe simulimi është më i rëndësishëm se kurrë më parë në historinë e njerëzimit, gjë që na nevojitet për të krijuar bazën më kritikë për zgjidhjen e një problem të caktuar …


Rrjetat Wlan Planifikimi Dhe Projektimi, Drilon Manaj Jan 2012

Rrjetat Wlan Planifikimi Dhe Projektimi, Drilon Manaj

Theses and Dissertations

Qëllimi i këtij punimi është që të studiohen dhe analizohen përformancat dhe problemet e WLAN nga aspekti i planifikimit dhe konstruktimit të këtyre rrjetave, llogaritjes së numrit të AP-ve dhe llogaritjes së lokacionit te tyre, planifikimit për kapacitet, planifikimit të frekuencave dhe sigurise etj. Planifikimi i këtyre pikave të lartpërmendura është më thelbësori sepse janë elemente të lidhura ngushtë me funksionimin e një WLAN-I me përformanca të mira. Në këtë punim të diplomës planifikimin e WLAN-it e kam ndarë në katër pjesë duke filluar nga kapitulli që e kam emëruar ‘Si të planifikohet WLAN-I’ në të cilin kam bërë përshkrimin …


An Investigation Into A Hybrid Genetic Programming And Ant Colony Optimization Method For Credit Scoring, Rojin Aliehyaei Jan 2012

An Investigation Into A Hybrid Genetic Programming And Ant Colony Optimization Method For Credit Scoring, Rojin Aliehyaei

Theses and Dissertations

This thesis proposes and investigates a new hybrid technique based on Genetic Programming (GP) and Ant Colony Optimization (ACO) techniques for inducing data classification rules. The proposed hybrid approach aims to improve on the accuracy of data classification rules produced by the original GP technique, which uses randomly generated initial populations. This hybrid technique relies on the ACO technique to produce the initial populations for the GP technique. To evaluate and compare their effectiveness in producing good data classification rules, GP, ACO, and hybrid techniques were implemented in the C programming language. The data classification rules were created and evaluated …


A General Model For Continuous Noninvasive Pulmonary Artery Pressure Estimation, Robert Anthony Smith Dec 2011

A General Model For Continuous Noninvasive Pulmonary Artery Pressure Estimation, Robert Anthony Smith

Theses and Dissertations

Elevated pulmonary artery pressure (PAP) is a significant healthcare risk. Continuous monitoring for patients with elevated PAP is crucial for effective treatment, yet the most accurate method is invasive and expensive, and cannot be performed repeatedly. Noninvasive methods exist but are inaccurate, expensive, and cannot be used for continuous monitoring. We present a machine learning model based on heart sounds that estimates pulmonary artery pressure with enough accuracy to exclude an invasive diagnostic operation, allowing for consistent monitoring of heart condition in suspect patients without the cost and risk of invasive monitoring. We conduct a greedy search through 38 possible …