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Air Force Institute of Technology

Theses and Dissertations

2012

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Articles 1 - 30 of 69

Full-Text Articles in Physical Sciences and Mathematics

Passive Ranging Using A Dispersive Spectrometer And Optical Filters, Jacob A. Martin Dec 2012

Passive Ranging Using A Dispersive Spectrometer And Optical Filters, Jacob A. Martin

Theses and Dissertations

Monocular passive ranging using atmospheric oxygen absorption has been demonstrated in the past using an FTS. These instruments are very sensitive to vibration making them di cult to use on an airborne platform. This work focuses on whether passive ranging can be done with instruments that are easier to deploy. Two potential instruments are tested and compared: a diffraction grating spectrometer and optical filters. A grating spectrometer was able to estimate range to within 5% for a static solid rocket motor ring at a distance of 910 m using the NIR absorption band of oxygen. Testing at shorter ranges produced …

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Epr And Endor Studies Of Point Defects In Lithium Tetraborate Crystals, Douglas A. Buchanan Dec 2012

Epr And Endor Studies Of Point Defects In Lithium Tetraborate Crystals, Douglas A. Buchanan

Theses and Dissertations

Lithium tetraborate (Li2B4O7 or LTB) is a promising material for both radiation dosimetry and neutron detection applications. LTB crystals can be grown pure or doped with different impurities including transition-metal and rare-earth ions. Research in this dissertation focuses on undoped LTB crystals and LTB crystals doped with copper and silver. Electron paramagnetic resonance (EPR) and electron-nuclear double resonance (ENDOR) are used to characterize point defects in the lithium tetraborate crystals. Thermoluminescence (TL), photoluminescence (PL), photoluminescence excitation (PLE), and optical absorption (OA) are also used. An intrinsic hole trap associated with lithium vacancies is characterized with EPR and ENDOR and its …

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Parametrizing Finite Frames And Optimal Frame Completions, Miriam J. Poteet Dec 2012

Parametrizing Finite Frames And Optimal Frame Completions, Miriam J. Poteet

Theses and Dissertations

Frames are used in many signal processing applications. We consider the problem of constructing every frame whose frame operator has a given spectrum and whose vectors have prescribed lengths. For a given spectrum and set of lengths, we know when such a frame exists by the Schur-Horn Theorem; it exists if and only if its spectrum majorizes its squared lengths. We provide a more constructive proof of Horn's original result. This proof is based on a new method for constructing any and all frames whose frame operator has a prescribed spectrum and whose vectors have prescribed lengths. Constructing all such …

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Quantifying Performance Bias In Label Fusion, Alexander M. Venzin Sep 2012

Quantifying Performance Bias In Label Fusion, Alexander M. Venzin

Theses and Dissertations

Classification systems are employed to remotely assess whether an element of interest falls into a target class or non-target class. These systems have uses in fields as far ranging as biostatistics to search engine keyword analysis. The performance of the system is often summarized as a trade-off between the proportions of elements correctly labeled as target plotted against the number of elements incorrectly labeled as target. These are empirical estimates of the true positive and false positive rates. These rates are often plotted to create a receiver operating characteristic (ROC) curve that acts as a visual tool to assess classification …

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Utilizing Graphics Processing Units For Network Anomaly Detection, Jonathan D. Hersack Sep 2012

Utilizing Graphics Processing Units For Network Anomaly Detection, Jonathan D. Hersack

Theses and Dissertations

This research explores the benefits of using commonly-available graphics processing units (GPUs) to perform classification of network traffic using supervised machine learning algorithms. Two full factorial experiments are conducted using a NVIDIA GeForce GTX 280 graphics card. The goal of the first experiment is to create a baseline for the relative performance of the CPU and GPU implementations of artificial neural network (ANN) and support vector machine (SVM) detection methods under varying loads. The goal of the second experiment is to determine the optimal ensemble configuration for classifying processed packet payloads using the GPU anomaly detector. The GPU ANN achieves …

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Effects Of Architecture On Information Leakage Of A Hardware Advanced Encryption Standard Implementation, Eric A. Koziel Sep 2012

Effects Of Architecture On Information Leakage Of A Hardware Advanced Encryption Standard Implementation, Eric A. Koziel

Theses and Dissertations

Side-channel analysis (SCA) is a threat to many modern cryptosystems. Many countermeasures exist, but are costly to implement and still do not provide complete protection against SCA. A plausible alternative is to design the cryptosystem using architectures that are known to leak little information about the cryptosystem's operations. This research uses several common primitive architectures for the Advanced Encryption Standard (AES) and assesses the susceptibility of the full AES system to side-channel attack for various primitive configurations. A combined encryption/decryption core is also evaluated to determine if variation of high-level architectures affects leakage characteristics. These different configurations are evaluated under …

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Creating Network Attack Priority Lists By Analyzing Email Traffic Using Predefined Profiles, Eric J. Merrit Sep 2012

Creating Network Attack Priority Lists By Analyzing Email Traffic Using Predefined Profiles, Eric J. Merrit

Theses and Dissertations

Networks can be vast and complicated entities consisting of both servers and workstations that contain information sought by attackers. Searching for specific data in a large network can be a time consuming process. Vast amounts of data either passes through or is stored by various servers on the network. However, intermediate work products are often kept solely on workstations. Potential high value targets can be passively identified by comparing user email traffic against predefined profiles. This method provides a potentially smaller footprint on target systems, less human interaction, and increased efficiency of attackers. Collecting user email traffic and comparing each …

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Mapping Nuclear Fallout Using The Weather Research & Forecasting (Wrf) Model, Joseph C. Schofield Sep 2012

Mapping Nuclear Fallout Using The Weather Research & Forecasting (Wrf) Model, Joseph C. Schofield

Theses and Dissertations

There are many models that attempt to predict transport & dispersion (T&D) of particulate matter in the sensible atmosphere. The majority of these existing models are unable to incorporate atmospheric processes such wet deposition through scavenging and cloud condensation nuclei (CCN) formation. To this end, the numerical weather prediction (NWP) model known as the Weather Research & Forecasting with Chemistry (WRF/Chem) Model is studied to determine its suitability as a potential tool for predicting particulate T&D following an atmospheric nuclear detonation. This is done by modifying relevant modules, originally designed to predict the settling of volcanic ash, such that a …

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Cross Hallway Detection And Indoor Localization Using Flash Laser Detection And Ranging, Istvan M. Prileszky Jun 2012

Cross Hallway Detection And Indoor Localization Using Flash Laser Detection And Ranging, Istvan M. Prileszky

Theses and Dissertations

A flash LADAR is investigated as a source of navigation information to support cross-hallway detection and relative localization. To accomplish this, a dynamic, flexible simulation was developed that simulated the LADAR and the noise of a LADAR system. Using simulated LADAR data, algorithms were developed that were shown to be effective at detecting cross hallways in simulated ideal environments and in simulated environments with noise. Relative position was determined in the same situations. A SwissRanger SR4000 flash LADAR was then used to collect real data and to verify algorithm performance in real environments. Hallway detection was shown to be possible …

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Decentralized Riemannian Particle Filtering With Applications To Multi-Agent Localization, Martin J. Eilders Jun 2012

Decentralized Riemannian Particle Filtering With Applications To Multi-Agent Localization, Martin J. Eilders

Theses and Dissertations

The primary focus of this research is to develop consistent nonlinear decentralized particle filtering approaches to the problem of multiple agent localization. A key aspect in our development is the use of Riemannian geometry to exploit the inherently non-Euclidean characteristics that are typical when considering multiple agent localization scenarios. A decentralized formulation is considered due to the practical advantages it provides over centralized fusion architectures. Inspiration is taken from the relatively new field of information geometry and the more established research field of computer vision. Differential geometric tools such as manifolds, geodesics, tangent spaces, exponential, and logarithmic mappings are used …

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The White-Hat Bot: A Novel Botnet Defense Strategy, Tyrone C. Gubler Jun 2012

The White-Hat Bot: A Novel Botnet Defense Strategy, Tyrone C. Gubler

Theses and Dissertations

Botnets are a threat to computer systems and users around the world. Botmasters can range from annoying spam email propagators to nefarious criminals. These criminals attempt to take down networks or web servers through distributed denial-of-service attacks, to steal corporate secrets, or to launder money from individuals or corporations. As the number and severity of successful botnet attacks rise, computer security experts need to develop better early-detection and removal techniques to protect computer networks and individual computer users from these very real threats. I will define botnets and describe some of their common purposes and current uses. Next, I will …

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Forensic Memory Analysis For Apple Os X, Andrew F. Hay Jun 2012

Forensic Memory Analysis For Apple Os X, Andrew F. Hay

Theses and Dissertations

Analysis of raw memory dumps has become a critical capability in digital forensics because it gives insight into the state of a system that cannot be fully represented through traditional disk analysis. Interest in memory forensics has grown steadily in recent years, with a focus on the Microsoft Windows operating systems. However, similar capabilities for Linux and Apple OS X have lagged by comparison. The volafox open source project has begun work on structured memory analysis for OS X. The tool currently supports a limited set of kernel structures to parse hardware information, system build number, process listing, loaded kernel …

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Vulnerability Analysis Of The Player Command And Control Protocol, John T. Hagen Jun 2012

Vulnerability Analysis Of The Player Command And Control Protocol, John T. Hagen

Theses and Dissertations

The Player project is an open-source effort providing a control interface specification and software framework for abstracting robot hardware. This research presents five exploits that compromise vulnerabilities in Player's command and control protocol. The attacks exploit weaknesses in the ARP, IP, TCP and Player protocols to compromise the confidentially, integrity, and availability of communication between a Player client and server. The attacks assume a laptop is connected in promiscuous mode to the same Ethernet hub as the client and server in order to sniff all network traffic between them. This work also demonstrates that Internet Protocol Security (IPsec) is capable …

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Enhancing Trust In The Smart Grid By Applying A Modified Exponentially Weighted Averages Algorithm, Andrew T. Kasperek Jun 2012

Enhancing Trust In The Smart Grid By Applying A Modified Exponentially Weighted Averages Algorithm, Andrew T. Kasperek

Theses and Dissertations

The main contribution of this thesis is the development and application of a modified Exponentially Weighted Moving Algorithm (EWMA) algorithm, and its ability to robustly function in the face varying numbers of bad (malicious or malfunctioning) Special Protection System (SPS) nodes. Simulation results support the use of the proposed modified EWMA reputation based trust module in SPSs within a smart grid environment. This modification results in the ability to easily maintain the system above the minimum acceptable frequency of 58.8 Hz at the 95% confidence interval, when challenged with test cases containing 5, 10 and 15 bad node test cases …

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Process Flow Features As A Host-Based Event Knowledge Representation, Benhur E. Pacer Jun 2012

Process Flow Features As A Host-Based Event Knowledge Representation, Benhur E. Pacer

Theses and Dissertations

The detection of malware is of great importance but even non-malicious software can be used for malicious purposes. Monitoring processes and their associated information can characterize normal behavior and help identify malicious processes or malicious use of normal process by measuring deviations from the learned baseline. This exploratory research describes a novel host feature generation process that calculates statistics of an executing process during a window of time called a process flow. Process flows are calculated from key process data structures extracted from computer memory using virtual machine introspection. Each flow cluster generated using k-means of the flow features represents …

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Resource Provisioning In Large-Scale Self-Organizing Distributed Systems, M. Brent Reynolds Jun 2012

Resource Provisioning In Large-Scale Self-Organizing Distributed Systems, M. Brent Reynolds

Theses and Dissertations

This dissertation researches the mathematical translation of resource provisioning policy into mathematical terms and parameters to solve the on-line service placement problem. A norm called the Provisioning Norm is introduced. Theorems presented in the work show the Provisioning Norm utility function and greedy, random, local search effectively and efficiently solve the on-line problem. Caching of placements is shown to reduce the cost of change but does not improve response time performance. The use of feedback control theory is shown to be effective at significantly improving performance but increases the cost of change. The theoretical results are verified using a decentralized, …

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Implementation Of Branch-Point-Tolerant Wavefront Reconstructor For Strong Turbulence Compensation, Michael J. Steinbock Jun 2012

Implementation Of Branch-Point-Tolerant Wavefront Reconstructor For Strong Turbulence Compensation, Michael J. Steinbock

Theses and Dissertations

Branch points arise in optical transmissions due to strong atmospheric turbulence, long propagation paths, or a combination of both. Unfortunately, these conditions are very often present in desired operational scenarios for laser weapon systems, optical communication, and covert imaging, which suffer greatly when traditional adaptive optics systems either cannot sense branch points or implement non-optimal methods for sensing and correcting branch points. Previous research by Pellizzari presented a thorough analysis of various novel branch point tolerant reconstructors in the absence of noise. In this research a realistic model of the Air Force Institute of Technology's adaptive optics system is developed …

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Calibration Of A Silver Detector Using A Pube Source, Melanie E. Mace Jun 2012

Calibration Of A Silver Detector Using A Pube Source, Melanie E. Mace

Theses and Dissertations

During the initial design of the Field Reversed Compression and Heating Experiment (FRCHX), magnetohydrodynamic simulations performed by Los Alamos National Laboratory using MACH2 predicted a neutron yield on the order of 1012 neutrons. However, Air Force Research Laboratory (AFRL) measurements indicate a total of 107-108 neutrons are generated from the FRCHX. A PuBe source was used to create a burst of neutrons to calibrate an AFRL silver detector based on distance to determine if the four order of magnitude discrepancy was cause by an improperly calibrated detector. It was determined that the calibration equation in use …

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Application Of An Imaging Fourier-Transform Spectrometer For The Means Of Combustion Diagnostics, Michael R. Rhoby Jun 2012

Application Of An Imaging Fourier-Transform Spectrometer For The Means Of Combustion Diagnostics, Michael R. Rhoby

Theses and Dissertations

A passive remote sensing technique for accurately monitoring the combustion efficiency of petrochemical flares is greatly desired. A Phase II DOE-funded SBIR lead by Spectral Sciences, Inc. is underway to develop such a method. This paper presents an overview of the progress of AFIT's contribution. A Telops Hyper-Cam Mid-wave infrared imaging Fourier-transform spectrometer is used to examine a flame produced by a Hencken burner. Ethylene fuel was burned at four different equivalency ratios φ = 0:80; 0:91; 1:0 and 1:25. Presented is qualitative spectrally-resolved visualization of a Hencken burner flame and the spatial distribution of combustion by-products. The flame spectra …

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Short Message Service (Sms) Command And Control (C2) Awareness In Android-Based Smartphones Using Kernel-Level Auditing, Robert J. Olipane Jun 2012

Short Message Service (Sms) Command And Control (C2) Awareness In Android-Based Smartphones Using Kernel-Level Auditing, Robert J. Olipane

Theses and Dissertations

This thesis addresses the emerging threat of botnets in the smartphone domain and focuses on the Android platform and botnets using short message service (SMS) as the command and control (C2) channel. With any botnet, C2 is the most important component contributing to its overall resilience, stealthiness, and effectiveness. This thesis develops a passive host-based approach for identifying covert SMS traffic and providing awareness to the user. Modifying the kernel and implementing this awareness mechanism is achieved by developing and inserting a loadable kernel module that logs all inbound SMS messages as they are sent from the baseband radio to …

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Using Predictive Analytics To Detect Major Problems In Department Of Defense Acquisition Programs, Austin W. Dowling Mar 2012

Using Predictive Analytics To Detect Major Problems In Department Of Defense Acquisition Programs, Austin W. Dowling

Theses and Dissertations

This research provides program analysts and Department of Defense (DoD) leadership with an approach to identify problems in real-time for acquisition contracts. Specifically, we develop optimization algorithms to detect unusual changes in acquisition programs’ Earned Value data streams. The research is focused on three questions. First, can we predict the contractor provided estimate at complete (EAC)? Second, can we use those predictions to develop an algorithm to determine if a problem will occur in an acquisition program or subprogram? Lastly, can we provide the probability of a problem occurring within a given timeframe? We find three of our models establish …

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Electrical And Optical Characterization Of Si-Ge-Sn, Merle D. Hamilton Mar 2012

Electrical And Optical Characterization Of Si-Ge-Sn, Merle D. Hamilton

Theses and Dissertations

The electrical characterization of boron-doped p-Si0.08Ge0.90Sn0.02/p-Ge(100) and p-Si0.112Ge0.86Sn0.028/n-Si(100) with various epilayer thicknesses was measured using the Hall effect. The room temperature sheet carrier concentration ranged from 1.21 x 1013 – 1.32 x 1016 cm-2. The room temperature mobilities were measured to be between 166 and 717 cm2/V·s, depending on sample composition. In the low temperature regime, the mobility was mainly affected by ionized impurity scattering. In the high temperature regime, the mobility was mainly affected by …

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Incorporating Externalities And Uncertainty Into Life-Cycle Cost Analysis, Alec C. Danaher Mar 2012

Incorporating Externalities And Uncertainty Into Life-Cycle Cost Analysis, Alec C. Danaher

Theses and Dissertations

Executive Order 13514 requires federal agencies to consider economic and social benefits and costs when evaluating projects and activities based on life-cycle return on investment. The generation of energy used by federal facilities imposes social externalities, most notably air pollution, upon society. This research utilized the social costs of carbon dioxide, oxides of nitrogen, and sulfur dioxide to develop a probabilistic life-cycle full-cost analysis tool for the analysis of energy efficiency projects. The tool was then used to investigate the effects of incorporating social externalities and uncertainty into life-cycle cost analyses of energy efficiency projects. Calculation of the social benefits …

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Analysis Of The Impact Of Data Normalization On Cyber Event Correlation Query Performance, Smile T. Ludovice Mar 2012

Analysis Of The Impact Of Data Normalization On Cyber Event Correlation Query Performance, Smile T. Ludovice

Theses and Dissertations

A critical capability required in the operation of cyberspace is the ability to maintain situational awareness of the status of the infrastructure elements that constitute cyberspace. Event logs from cyber devices can yield significant information, and when properly utilized they can provide timely situational awareness about the state of the cyber infrastructure. In addition, proper Information Assurance requires the validation and verification of the integrity of results generated by a commercial log analysis tool. Event log analysis can be performed using relational databases. To enhance database query performance, previous literatures affirm denormalization of databases. Yet database normalization can also increase …

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Modeling The Impact Of Cracking In Low Permeability Layers In A Groundwater Contamination Source Zone On Dissolved Contamination Source Zone On Dissolved Contaminant Fate And Transport, Katherine W. Sievers Mar 2012

Modeling The Impact Of Cracking In Low Permeability Layers In A Groundwater Contamination Source Zone On Dissolved Contamination Source Zone On Dissolved Contaminant Fate And Transport, Katherine W. Sievers

Theses and Dissertations

The storage and transport of a dense non-aqueous phase liquid (DNAPL) was evaluated using a numerical model. Many DNAPLs are used as solvents by the DoD and industry. The improper disposal and handling of these chemicals has led to long term contamination of groundwater. When spilled, a DNAPL will pool atop low permeability layers and slowly dissolve creating a contaminant plume. The dissolved contaminant within a low permeability layer serves as long-term sources of contamination once the source is removed. In this study, cracks are hypothesized to exist in the low permeability layers, allowing for enhanced transport. A numerical model …

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Emissions From Simulated Open Burning Of Deployed Us Military Waste, Brian D. Woodall Mar 2012

Emissions From Simulated Open Burning Of Deployed Us Military Waste, Brian D. Woodall

Theses and Dissertations

U.S. military forces have relied primarily on open burning as an expedient method of volume reduction and treatment of solid waste during the conflicts in Afghanistan and Iraq. This study is the first effort to characterize a broad range of pollutants and their emission factors during the burning of military waste and the effects that recycling efforts, namely removing plastics, might have on emissions. Piles of simulated military waste were constructed, burned, and emissions sampled at the U.S. Environmental Protection Agency (EPA) Open Burn Testing Facility (OBTF), Research Triangle Park, NC. Three tests contained polyethylene terephthalate (PET #1 or PET) …

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Determining Angular Frequency From A Video With A Generalized Fast Fourier Transform, Lindsay N. Smith Mar 2012

Determining Angular Frequency From A Video With A Generalized Fast Fourier Transform, Lindsay N. Smith

Theses and Dissertations

Suppose we are given a video of a rotating object and suppose we want to determine the rate of rotation solely from the video itself and its known frame rate. In this thesis, we present a new mathematical operator called the Geometric Sum Transform (GST) that can help one determine the angular frequency of the object in question. The GST is a generalization of the discrete Fourier transform (DFT) and as such, the two transforms have much in common. However, whereas the DFT is applied to a sequence of scalars, the GST can be applied to a sequence of vectors. …

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A Dempster-Shafer Method For Multi-Sensor Fusion, Bethany G. Foley Mar 2012

A Dempster-Shafer Method For Multi-Sensor Fusion, Bethany G. Foley

Theses and Dissertations

The Dempster-Shafer Theory, a generalization of the Bayesian theory, is based on the idea of belief and as such can handle ignorance. When all of the required information is available, many data fusion methods provide a solid approach. Yet, most do not have a good way of dealing with ignorance. In the absence of information, these methods must then make assumptions about the sensor data. However, the real data may not fit well within the assumed model. Consequently, the results are often unsatisfactory and inconsistent. The Dempster-Shafer Theory is not hindered by incomplete models or by the lack of prior …

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A Women-Only Comparision Of The U.S. Air Force Fitness Test And The Marine Combat Fitness Test, Tarah D. Mitchell Mar 2012

A Women-Only Comparision Of The U.S. Air Force Fitness Test And The Marine Combat Fitness Test, Tarah D. Mitchell

Theses and Dissertations

In 2009, Captain Thomas Worden determined the Air Force Physical Fitness Test (AFPFT) poorly predicted combat capability for his 86 study participants. With only 5 of these 86 volunteers being women, this limited Worden's findings to primarily men. This follow-on research investigated whether these results carried over to women. We recruited 61 female volunteers and compared their performance on the AFPFT to the Marine Combat Fitness Test, the proxy for combat capability. Like Worden's research, we discovered little association between the two (R2 of 0.161). However, this association significantly increased (adj R2 of 0.572) when utilizing the raw …

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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 …

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