Current Search: security (x)
Pages
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Title
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Three Studies of Stakeholder Influence in the Formation and Management of Tax Policies.
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Creator
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Chen, Jason, Roberts, Robin, Schmitt, Donna, Robb, Sean, Patten, Dennis, University of Central Florida
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Abstract / Description
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This dissertation consists of three separate but interrelated studies examining the formation and management of tax policies. The first study uses stakeholder theory (ST) to investigate the strategic management practices of the Transport for London (TfL) during discrete stages in the adoption, implementation, and amendments of the tax policy reform known as the London Congestion Charge (LCC). Results indicate that TfL has utilized power, legitimacy, and urgency as its main policy management...
Show moreThis dissertation consists of three separate but interrelated studies examining the formation and management of tax policies. The first study uses stakeholder theory (ST) to investigate the strategic management practices of the Transport for London (TfL) during discrete stages in the adoption, implementation, and amendments of the tax policy reform known as the London Congestion Charge (LCC). Results indicate that TfL has utilized power, legitimacy, and urgency as its main policy management tactics with a significant emphasis on legitimatizing the LCC and its subsequent policy amendments.The second study draws on social exchange theory (SET) to reexamine the relationship between corporations and legislators during tax policy processes. Data for the study come from publicly available political action committee (PAC) contribution activities surrounding the Energy Independence and Security Act of 2007 (EISA07). By examining the endogeneity between legislators' voting patterns and PAC contributions by corporations, this study aims to refine empirical work on corporate political strategy, especially as it relates to crucial tax provisions embedded within an intensely debated policy proposal. Using simultaneous equations modeling (SEM), results are consistent with SET showing that an implicit and reciprocal relationship exists between corporations and legislators. This relationship affects the interdependence of how legislators vote for public policies and the amount of corporations' financial contributions to legislators.The third study investigates and aims to validate the empirical applicability of Dahan's (2005) typology of political resources in explicating the political interactions between stakeholder groups and legislators in the development of EISA07. I discuss how and why the mode of operations and various political resources employed by stakeholder groups affected the final EISA07 language concerning domestic production deduction tax credits for the oil and gas industry. Publicly available data show that both supporting and opposing stakeholder groups employ tactics consistent with Dahan's (2005) typology. However, both stakeholder groups tend to use an interactive or positive political approach to gain access and favor of legislators instead of an adversarial approach. Ultimately, the tax credits were preserved. Taken as a whole, the three studies advance the tax and public policy research literature in accounting by studying how and why relevant stakeholders affect the formation and ongoing management of public and tax policies.
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Date Issued
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2012
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Identifier
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CFE0004343, ucf:49423
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0004343
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Title
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Federal, State and Local Law Enforcement Agency Interoperability Capabilities and Cyber Vulnerabilities.
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Creator
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Trapnell, Tyrone, Caulkins, Bruce, Wiegand, Rudolf, Bockelman, Patricia, Canham, Matthew, University of Central Florida
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Abstract / Description
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The National Data Exchange (N-DEx) System is the central informational hub located at the Federal Bureau of Investigation (FBI). Its purpose is to provide network subscriptions to all Federal, state and local level law enforcement agencies while increasing information collaboration across all domains. The National Data Exchange users must satisfy the Advanced Permission Requirements, confirming the terms of N-DEx information use, and the Verification Requirement (verifying the completeness,...
Show moreThe National Data Exchange (N-DEx) System is the central informational hub located at the Federal Bureau of Investigation (FBI). Its purpose is to provide network subscriptions to all Federal, state and local level law enforcement agencies while increasing information collaboration across all domains. The National Data Exchange users must satisfy the Advanced Permission Requirements, confirming the terms of N-DEx information use, and the Verification Requirement (verifying the completeness, timeliness, accuracy, and relevancy of N-DEx information) through coordination with the record-owning agency (Management, 2018). A network infection model is proposed to simulate the spread impact of various cyber-attacks within Federal, state and local level law enforcement networks that are linked together through the topologies merging with the National Data Exchange (N-DEx) System as the ability to manipulate the live network is limited. The model design methodology is conducted in a manner that creates a level of organization from the state level to the local level of law enforcement agencies allowing for each organizational infection probability to be calculated and entered, thus making the model very specific in nature for determining spread or outbreaks of cyber-attacks among law enforcement agencies at all levels. This research will enable future researchers to further develop a model that is capable of detecting weak points within an information structure when multiple topologies merge, allowing for more secure operations among law enforcement networks.
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Date Issued
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2019
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Identifier
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CFE0007543, ucf:52621
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0007543
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Title
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Pervasive Secure Content Delivery Networks Implementation.
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Creator
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Lugo-Cordero, Hector, Guha, Ratan, Stanley, Kenneth, Chatterjee, Mainak, Wu, Annie, Lu, Kejie, University of Central Florida
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Abstract / Description
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Over the years, communication networks have been shifting their focus from providing connectivity in a client/server model to providing a service or content. This shift has led to topic areas like Service-Oriented Architecture (SOA), Heterogeneous Wireless Mesh Networks, and Ubiquitous Computing. Furthermore, probably the broadest of these areas which embarks all is the Internet of Things (IoT). The IoT is defined as an Internet where all physical entities (e.g., vehicles, appliances, smart...
Show moreOver the years, communication networks have been shifting their focus from providing connectivity in a client/server model to providing a service or content. This shift has led to topic areas like Service-Oriented Architecture (SOA), Heterogeneous Wireless Mesh Networks, and Ubiquitous Computing. Furthermore, probably the broadest of these areas which embarks all is the Internet of Things (IoT). The IoT is defined as an Internet where all physical entities (e.g., vehicles, appliances, smart phones, smart homes, computers, etc.), which we interact daily are connected and exchanging data among themselves and users. The IoT has become a global goal for companies, researchers, and users alike due to its different implementation and functional benefits: performance efficiency, coverage, economic and health. Due to the variety of devices which connect to it, it is expected that the IoT is composed of multiple technologies interacting together, to deliver a service. This technologies interactions renders an important challenge that must be overcome: how to communicate these technologies effectively and securely? The answer to this question is vital for a successful deployment of IoT and achievement of all the potential benefits that the IoT promises.This thesis proposes a SOA approach at the Network Layer to be able to integrate all technologies involved, in a transparent manner. The proposed set of solutions is composed of primarily the secure implementation of a unifying routing algorithm and a layered messaging model to standardizecommunication of all devices. Security is targeted to address the three main security concerns (i.e., confidentiality, integrity, and availability), with pervasive schemes that can be employed for any kind of device on the client, backbone, and server side. The implementation of such schemes is achieved by standard current security mechanisms (e.g., encryption), in combination with novel context and intelligent checks that detect compromised devices. Moreover, a decentralized content processing design is presented. In such design, content processing is handled at the client side, allowing server machines to serve more content, while being more reliable and capable of processing complete security checks on data and client integrity.
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Date Issued
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2017
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Identifier
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CFE0006620, ucf:51268
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0006620
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Title
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Microgrid Control and Protection: Stability and Security.
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Creator
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Keshavarztalebi, Morteza, Behal, Aman, Haralambous, Michael, Sun, Wei, Jain, Amit Kumar, Kutkut, Nasser, University of Central Florida
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Abstract / Description
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When the microgrid disconnects from the main grid in response to, say, upstream disturbance orvoltage fluctuation and goes to islanding mode, both voltage and frequency at all locations in themicrogrid have to be regulated to nominal values in a short amount of time before the operation ofprotective relays. Motivated by this, we studied the application of intelligent pinning of distributed cooperative secondary control of distributed generators in islanded microgrid operation in a power...
Show moreWhen the microgrid disconnects from the main grid in response to, say, upstream disturbance orvoltage fluctuation and goes to islanding mode, both voltage and frequency at all locations in themicrogrid have to be regulated to nominal values in a short amount of time before the operation ofprotective relays. Motivated by this, we studied the application of intelligent pinning of distributed cooperative secondary control of distributed generators in islanded microgrid operation in a power system. In the first part, the problem of single and multi-pinning of distributed cooperative secondary control of DGs in a microgrid is formulated. It is shown that the intelligent selection of a pinning set based on the number of its connections and distance of leader DG/DGs from the rest of the network, i.e., degree of connectivity, strengthens microgrid voltage and frequency regulation performance both in transient and steady state. The proposed control strategy and algorithm are validated by simulation in MATLAB/SIMULINK using different microgrid topologies. It is shown that it is much easier to stabilize the microgrid voltage and frequency in islanding mode operationby specifically placing the pinning node on the DGs with high degrees of connectivity than byrandomly placing pinning nodes into the network. In all of these research study cases, DGs areonly required to communicate with their neighboring units which facilitates the distributed controlstrategy.Historically, the models for primary control are developed for power grids with centralized powergeneration, in which the transmission lines are assumed to be primarily inductive. However, fordistributed power generation, this assumption does not hold since the network has significant resistive impedance as well. Hence, it is of utmost importance to generalize the droop equations, i.e., primary control, to arrive at a proper model for microgrid systems. Motivated by this, we proposed the secondary adaptive voltage and frequency control of distributed generators for low and medium voltage microgrid in autonomous mode to overcome the drawback of existing classical droop based control techniques. Our proposed secondary control strategy is adaptive with line parameters and can be applied to all types of microgrids to address the simultaneous impacts of active and reactive power on the microgrids voltage and frequency. Also, since the parameters in the network model are unknown or uncertain, the second part of our research studies adaptive distributed estimation/compensation. It is shown that this is an effective method to robustly regulate the microgrid variables to their desired values.The security of power systems against malicious cyberphysical data attacks is the third topic of this dissertation. The adversary always attempts to manipulate the information structure of the power system and inject malicious data to deviate state variables while evading the existing detection techniques based on residual test. The solutions proposed in the literature are capable of immunizing the power system against false data injection but they might be too costly and physically not practical in the expansive distribution network. To this end, we define an algebraic condition for trustworthy power system to evade malicious data injection. The proposed protection scheme secures the power system by deterministically reconfiguring the information structure and corresponding residual test. More importantly, it does not require any physical effort in either microgrid or network level. The identification scheme of finding meters being attacked is proposed as well. Eventually, a well-known IEEE 30-bus system is adopted to demonstrate the effectiveness of the proposed schemes.
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Date Issued
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2016
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Identifier
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CFE0006338, ucf:51569
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0006338
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Title
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An Evaluation Study of the Implementation of Webcam Proctoring for Secure Testing in a K-12 Virtual School.
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Creator
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Geiser Hogan, Elena, Gunter, Glenda, Hartshorne, Richard, Boote, David, Kennedy, Kathryn, Gordon, William, University of Central Florida
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Abstract / Description
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ABSTRACT The purpose of this evaluative study was to review the implementation of a Webcam Test-Proctoring Program (WTPP) implemented in a Kindergarten through 12th grade public virtual school. Results of the evaluative study will be used to determine if the secure Webcam proctoring method would be a viable solution to a problem of practice(-)requiring full-time virtual school students to participate in the multitude of required state and Florida school district assessments. At the core of...
Show moreABSTRACT The purpose of this evaluative study was to review the implementation of a Webcam Test-Proctoring Program (WTPP) implemented in a Kindergarten through 12th grade public virtual school. Results of the evaluative study will be used to determine if the secure Webcam proctoring method would be a viable solution to a problem of practice(-)requiring full-time virtual school students to participate in the multitude of required state and Florida school district assessments. At the core of virtual education lies the appeal of flexibility in each student's individual learning path. The rigid nature of secure assessments conflict with the intentions of a K-12 virtual school. Natale and Cook (2012) identified this as a problem of practice as well, stating, (")Digital learning de-standardizes and decentralizes educational delivery, so it presents challenges in applying quality control systems and metrics that were developed for more traditional school structures(") (p. 541).A formal evaluation included an electronic survey and one-on-one phone interviews. The sample population for this study included 6th-12th grade students (n = 27) who were enrolled in Hurricane County Virtual School during the 2014-2015 school year. The HCVS population was 165 at the beginning of the 2014-2015 school year, therefore the population for this study was N=165. The WTPP evaluated for this study took place over two test sessions, the first in October of 2014 and the second in January 2015. Students were asked to complete the electronic survey and to volunteer to complete phone interviews to provide feedback about their experience completing their benchmark assessments. In this mixed-methods study, an electronic survey created by the evaluator and research chair gathered quantitative data that were analyzed using descriptive and inferential statistics. In order to determine if there was any relationship between specific demographic sub-groups and their experiences and preferences regarding Webcam proctoring, the researcher used the Kruskal-Walis and Mann-Whitney inferential statistics. Additionally, qualitative data were collected through one-on-one phone interviews with six students who participated in the WTPP. Data from these interviews yielded supporting statements for the quantitative data analyzed. Results yielded from this study indicated that the majority of students who participated in the WTPP were satisfied or very satisfied with this method of proctoring for secure testing overall. Future studies should further evaluate the effectiveness of Webcam proctoring for secure testing and determine the impact of allowing students more flexibility (which Webcam proctoring inherently does) while testing has on their test scores.
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Date Issued
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2016
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Identifier
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CFE0006457, ucf:51441
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0006457
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Title
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Evaluation of a secure laptop based testing program in an undergraduate nursing program.
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Creator
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Tao, Jinyuan, Gunter, Glenda, Robinson, Edward, Vitale, Thomas, Hayes, Grant, University of Central Florida
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Abstract / Description
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This applied dissertation paper introduced a program evaluation of a secure laptop-based testing (SLBT) program, which was implemented from 2009 to 2014 in an undergraduate nursing program at a private institution in the southeastern region of the United States (US). Computerized testing is an old topic in the educational research field, but the instructor-made, laptop-based secure testing that utilizes learning management systems (LMS) for undergraduate nursing programs is a fairly new topic...
Show moreThis applied dissertation paper introduced a program evaluation of a secure laptop-based testing (SLBT) program, which was implemented from 2009 to 2014 in an undergraduate nursing program at a private institution in the southeastern region of the United States (US). Computerized testing is an old topic in the educational research field, but the instructor-made, laptop-based secure testing that utilizes learning management systems (LMS) for undergraduate nursing programs is a fairly new topic in the US. Traditionally, testing has been administered with paper and pencil in the undergraduate nursing programs in the US for security reasons. Recently, with different robust LMSs, together with availability of affordable laptops, SLBT has become a reality on many campuses. The undergraduate nursing program at the Adventist University of Health Sciences (ADU) began to implement the SLBT program in 2009, which allowed students to use their newly purchased laptops to take secure quizzes and tests in their classrooms. After nearly five years' SLBT program implementation, a formative evaluation was conducted to seek constructive feedback from students, faculty, and technology support personnel to improve the program. Evaluation data show that, overall, students believed the SLBT program help them get hands-on experience of taking exams on the computer and get them prepared for their National Council Licensure Examination for Registered Nurses (NCLEX-RN) which is also computerized. Students, however, had a lot of concerns on laptop glitches and campus wireless network glitches they experienced during testing. Faculty and technology support personnel, on the other hand, were very satisfied with the SLBT program. Another goal of this evaluation study was to determine if students' first-time passing rate of NCLEX-RN has been improved significantly after the implementation of the SLBT program. NCLEX-RN first-time passing rate data were analyzed using the Chi-Square test and it revealed that there was no significant association between the two types of testing method (paper-and-pencil testing and the secure laptop-based testing) and whether or not students would pass NCLEX-RN the first time X2(1) = 3.53, p (>) .05. Based on the odds ratio, however, the odds of students passed NCLEX-RN the first time were 1.37 times higher if they were taught with the SLBT testing method than if taught with the traditional paper-and-pencil testing method in nursing school.
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Date Issued
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2014
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Identifier
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CFE0005424, ucf:50421
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0005424
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Title
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HEALTHCARE COMMUNICATION NETWORKS: THE DISSEMINATION OF EMPLOYEE INFORMATION FOR HOSPITAL SECURITY.
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Creator
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Sumner, Jennifer, Liberman, Aaron, University of Central Florida
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Abstract / Description
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ABSTRACT: Healthcare in the United States is a system that, organizationally speaking, is fragmented. Each hospital facility is independently operated and is responsible for the hiring of its own employees. However, corrupt individuals can take advantage of this fragmentation and move from hospital to hospital, gaining employment while hiding previous employment history. Traditionally, hospitals have been reluctant to share information on their previous employees, even with other hospitals,...
Show moreABSTRACT: Healthcare in the United States is a system that, organizationally speaking, is fragmented. Each hospital facility is independently operated and is responsible for the hiring of its own employees. However, corrupt individuals can take advantage of this fragmentation and move from hospital to hospital, gaining employment while hiding previous employment history. Traditionally, hospitals have been reluctant to share information on their previous employees, even with other hospitals, for fear of issues surrounding defamation, negligent hiring, and violation of the employee's privacy. However, growth in healthcare services is expected to rise exponentially in the near future, increasing the demand for employees. The need, therefore, to exchange pertinent information regarding employees will become necessary as hospitals seek qualified employees to fill positions throughout their organizations. One way to promote this information exchange is to develop trusted information sharing networks among hospital units. This study examined the problems surrounding organizational information sharing as well as the current level of employee information sharing being conducted by hospitals nationwide. Utilizing a survey of hospital administrators, this study drew upon the theoretical foundations of the Diffusion of Innovation Theory, the Knowledge Management Theory, the Social Exchange Theory and the earlier organizational information sharing frameworks established by Dawes (1996) and Landsbergen and Wolken (1998; 2001) in order to examine the variables that contribute to propensity of hospital administrators to engage in the sharing of employee information with other organizations.
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Date Issued
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2008
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Identifier
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CFE0002010, ucf:47609
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0002010
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Title
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CENTRAL ASIAN SECURITY: WITH A FOCUS ON KAZAKHSTAN.
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Creator
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Bragg, Marcus, Sadri, Houman, University of Central Florida
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Abstract / Description
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This work focuses on the influence of terror, extremism, trafficking and corruption on the regional security of Central Asia, with a particular emphasis on Kazakhstan. Kazakhstan is regarded as the most stable and financially developed state in Central Asia, yet domestic and regional stability are threatened by the rise in extremism, narcotics trafficking, institutional corruption and acts of terrorism. The challenges of trafficking and extremism within the region originated from outside of...
Show moreThis work focuses on the influence of terror, extremism, trafficking and corruption on the regional security of Central Asia, with a particular emphasis on Kazakhstan. Kazakhstan is regarded as the most stable and financially developed state in Central Asia, yet domestic and regional stability are threatened by the rise in extremism, narcotics trafficking, institutional corruption and acts of terrorism. The challenges of trafficking and extremism within the region originated from outside of Central Asia. Foreign organizations and ideologies are significant actors in progression of regional instability. Government response to these challenges can perpetuate or stymie the aforementioned threats to regional security. Repressive regimes inadvertently contribute to the propaganda of the non-state foes. A prominent solution is the international program referred to as border management. This program aims to support border security while also promoting economic growth and ensuring the protection of human rights. Improved borders promotes regional security, economic growth can potentially undermine the growth of corruption and human rights protection can undermine a large part of extremist propaganda.
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Date Issued
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2014
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Identifier
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CFH0004604, ucf:45267
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFH0004604
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Title
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A COMPARATIVE ANALYSIS OF THE USA PATRIOT ACT OF 2001 TO THE USA FREEDOM ACT OF 2015: BALANCING SECURITY WITH LIBERTY.
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Creator
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Russo, Richard, Slaughter, David, University of Central Florida
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Abstract / Description
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Freedom and safety are two ideals that American citizens value greatly; however, the balance between privacy and security determines whether or not both can be achieved in a reasonable manner. Security and privacy are not mutually exclusive; however, they tend to exhibit an inverse correlation with regards to maintaining individual liberties. Security and privacy are highly beneficial, but when one is given too much weight, the other most often suffers. When the United States citizens are...
Show moreFreedom and safety are two ideals that American citizens value greatly; however, the balance between privacy and security determines whether or not both can be achieved in a reasonable manner. Security and privacy are not mutually exclusive; however, they tend to exhibit an inverse correlation with regards to maintaining individual liberties. Security and privacy are highly beneficial, but when one is given too much weight, the other most often suffers. When the United States citizens are given too much privacy through regulations, the citizens risk their well-being by not allowing the government the ability to prevent dangerous activities being done by criminals. Citizens are unable to defend themselves against foreign and domestic threats of terrorism that affect large amounts of people such as bombings in public settings; however, the federal government can help to prevent such attacks in public settings through surveillance of public areas and monitoring of internet and intracellular communications. When the United States federal government is given too much discretion in security powers through legislation, citizens are at risk of losing their civil rights granted in the Bill of Rights and in Supreme Court cases. The United States of America has had a dangerous imbalance of power in favor of national security since the adoption of the USA PATRIOT Act in 2001, and the imbalance has continued to the present even after the passage of the USA FREEDOM Act in 2015.This thesis will be a comparative analysis of the USA PATRIOT Act of 2001 to the USA FREEDOM Act of 2015. This thesis will show what specific powers are granted through provisions of the acts, whether or not the provisions are unconstitutional, how the privacy and security of American citizens will change due to the provisions in the USA FREEDOM Act, and suggestions for how the United States federal government can continue to tilt the balance between security and liberty to ensure more protection for civil liberties and a decrease in national security powers. The suggestions will include three options for gaining the protection of civil liberties and the elimination of certain national security powers and the options are through Supreme Court cases on national security laws pertaining to individual cases or states, Congress passing concurring minor bills with the proposed plan to fully repeal granted national security powers without disturbing congressional alliances on other measures, and Congress passing a single act called the State Surveillance Repeal Act in order to fully repeal the USA PATRIOT Act provisions that would still be in effect after the passage of the USA FREEDOM Act.
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Date Issued
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2015
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Identifier
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CFH0004862, ucf:45466
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFH0004862
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Title
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Appropriate Adjective: Executive Authority and the Classification of Enemy Combatants.
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Creator
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Davis, Taraleigh, Merriam, Eric, Bledsoe, Robert, Edwards, Barry, University of Central Florida
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Abstract / Description
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Is the term enemy combatant an established legal category of persons under international law? Has the President exceeded his constitutional authority in classifying United States citizens who are suspected terrorists as enemy combatants? In 2018 a U.S. citizen was released after being held for 13 months as an enemy combatant. He was detained without being charged with a crime and without the ability to challenge the legality of his detention. This thesis serves two purposes. First, it will...
Show moreIs the term enemy combatant an established legal category of persons under international law? Has the President exceeded his constitutional authority in classifying United States citizens who are suspected terrorists as enemy combatants? In 2018 a U.S. citizen was released after being held for 13 months as an enemy combatant. He was detained without being charged with a crime and without the ability to challenge the legality of his detention. This thesis serves two purposes. First, it will seek to trace the history of the term enemy combatant and highlight the evolution of its use by the executive branch. This thesis then examines whether the executive has exceeded his constitutional authority to classify a United States citizen as an enemy combatant. While most of the literature focuses on the treatment and detention of enemy combatants, existing scholarship largely overlooks the issue of authority to classify enemy combatants. This thesis will argue that the executive is overstepping the boundaries of its presidential power when the executive branch creates the criteria (a legislative function) for enemy combatants and applies the criteria in the classification of enemy combatants (a judicial function). This qualitative study will use normative legal research focusing on the principles of the law in classifying a suspected terrorist as an enemy combatant as well as the legal history of the term. The analysis of the legal history of the term enemy combatant will be completed by content analysis using Nvivo 12 software of various government documents as well as case studies of enemy combatant cases.
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Date Issued
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2019
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Identifier
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CFE0007448, ucf:52703
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0007448
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Title
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Security of Autonomous Systems under Physical Attacks: With application to Self-Driving Cars.
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Creator
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Dutta, Raj, Jin, Yier, Sundaram, Kalpathy, DeMara, Ronald, Zhang, Shaojie, Zhang, Teng, University of Central Florida
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Abstract / Description
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The drive to achieve trustworthy autonomous cyber-physical systems (CPS), which can attain goals independently in the presence of significant uncertainties and for long periods of time without any human intervention, has always been enticing. Significant progress has been made in the avenues of both software and hardware for fulfilling these objectives. However, technological challenges still exist and particularly in terms of decision making under uncertainty. In an autonomous system,...
Show moreThe drive to achieve trustworthy autonomous cyber-physical systems (CPS), which can attain goals independently in the presence of significant uncertainties and for long periods of time without any human intervention, has always been enticing. Significant progress has been made in the avenues of both software and hardware for fulfilling these objectives. However, technological challenges still exist and particularly in terms of decision making under uncertainty. In an autonomous system, uncertainties can arise from the operating environment, adversarial attacks, and from within the system. As a result of these concerns, human-beings lack trust in these systems and hesitate to use them for day-to-day use.In this dissertation, we develop algorithms to enhance trust by mitigating physical attacks targeting the integrity and security of sensing units of autonomous CPS. The sensors of these systems are responsible for gathering data of the physical processes. Lack of measures for securing their information can enable malicious attackers to cause life-threatening situations. This serves as a motivation for developing attack resilient solutions.Among various security solutions, attention has been recently paid toward developing system-level countermeasures for CPS whose sensor measurements are corrupted by an attacker. Our methods are along this direction as we develop an active and multiple passive algorithm to detect the attack and minimize its effect on the internal state estimates of the system. In the active approach, we leverage a challenge authentication technique for detection of two types of attacks: The Denial of Service (DoS) and the delay injection on active sensors of the systems. Furthermore, we develop a recursive least square estimator for recovery of system from attacks. The majority of the dissertation focuses on designing passive approaches for sensor attacks. In the first method, we focus on a linear stochastic system with multiple sensors, where measurements are fused in a central unit to estimate the state of the CPS. By leveraging Bayesian interpretation of the Kalman filter and combining it with the Chi-Squared detector, we recursively estimate states within an error bound and detect the DoS and False Data Injection attacks. We also analyze the asymptotic performance of the estimator and provide conditions for resilience of the state estimate.Next, we propose a novel distributed estimator based on l1 norm optimization, which could recursively estimate states within an error bound without restricting the number of agents of the distributed system that can be compromised. We also extend this estimator to a vehicle platoon scenario which is subjected to sparse attacks. Furthermore, we analyze the resiliency and asymptotic properties of both the estimators. Finally, at the end of the dissertation, we make an initial effort to formally verify the control system of the autonomous CPS using the statistical model checking method. It is done to ensure that a real-time and resource constrained system such as a self-driving car, with controllers and security solutions, adheres to strict timing constrains.
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Date Issued
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2018
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Identifier
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CFE0007174, ucf:52253
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0007174
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Title
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Masquerading Techniques in IEEE 802.11 Wireless Local Area Networks.
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Creator
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Nakhila, Omar, Zou, Changchun, Turgut, Damla, Bassiouni, Mostafa, Chatterjee, Mainak, Wang, Chung-Ching, University of Central Florida
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Abstract / Description
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The airborne nature of wireless transmission offers a potential target for attackers to compromise IEEE 802.11 Wireless Local Area Network (WLAN). In this dissertation, we explore the current WLAN security threats and their corresponding defense solutions. In our study, we divide WLAN vulnerabilities into two aspects, client, and administrator. The client-side vulnerability investigation is based on examining the Evil Twin Attack (ETA) while our administrator side research targets Wi-Fi...
Show moreThe airborne nature of wireless transmission offers a potential target for attackers to compromise IEEE 802.11 Wireless Local Area Network (WLAN). In this dissertation, we explore the current WLAN security threats and their corresponding defense solutions. In our study, we divide WLAN vulnerabilities into two aspects, client, and administrator. The client-side vulnerability investigation is based on examining the Evil Twin Attack (ETA) while our administrator side research targets Wi-Fi Protected Access II (WPA2). Three novel techniques have been presented to detect ETA. The detection methods are based on (1) creating a secure connection to a remote server to detect the change of gateway's public IP address by switching from one Access Point (AP) to another. (2) Monitoring multiple Wi-Fi channels in a random order looking for specific data packets sent by the remote server. (3) Merging the previous solutions into one universal ETA detection method using Virtual Wireless Clients (VWCs). On the other hand, we present a new vulnerability that allows an attacker to force the victim's smartphone to consume data through the cellular network by starting the data download on the victim's cell phone without the victim's permission. A new scheme has been developed to speed up the active dictionary attack intensity on WPA2 based on two novel ideas. First, the scheme connects multiple VWCs to the AP at the same time-each VWC has its own spoofed MAC address. Second, each of the VWCs could try many passphrases using single wireless session. Furthermore, we present a new technique to avoid bandwidth limitation imposed by Wi-Fi hotspots. The proposed method creates multiple VWCs to access the WLAN. The combination of the individual bandwidth of each VWC results in an increase of the total bandwidth gained by the attacker. All proposal techniques have been implemented and evaluated in real-life scenarios.
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Date Issued
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2018
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Identifier
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CFE0007063, ucf:51979
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0007063
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Title
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Energy Efficient and Secure Wireless Sensor Networks Design.
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Creator
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Attiah, Afraa, Zou, Changchun, Chatterjee, Mainak, Wang, Jun, Yuksel, Murat, Wang, Chung-Ching, University of Central Florida
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Abstract / Description
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ABSTRACTWireless Sensor Networks (WSNs) are emerging technologies that have the ability to sense,process, communicate, and transmit information to a destination, and they are expected to have significantimpact on the efficiency of many applications in various fields. The resource constraintsuch as limited battery power, is the greatest challenge in WSNs design as it affects the lifetimeand performance of the network. An energy efficient, secure, and trustworthy system is vital whena WSN...
Show moreABSTRACTWireless Sensor Networks (WSNs) are emerging technologies that have the ability to sense,process, communicate, and transmit information to a destination, and they are expected to have significantimpact on the efficiency of many applications in various fields. The resource constraintsuch as limited battery power, is the greatest challenge in WSNs design as it affects the lifetimeand performance of the network. An energy efficient, secure, and trustworthy system is vital whena WSN involves highly sensitive information. Thus, it is critical to design mechanisms that are energyefficient and secure while at the same time maintaining the desired level of quality of service.Inspired by these challenges, this dissertation is dedicated to exploiting optimization and gametheoretic approaches/solutions to handle several important issues in WSN communication, includingenergy efficiency, latency, congestion, dynamic traffic load, and security. We present severalnovel mechanisms to improve the security and energy efficiency of WSNs. Two new schemes areproposed for the network layer stack to achieve the following: (a) to enhance energy efficiencythrough optimized sleep intervals, that also considers the underlying dynamic traffic load and (b)to develop the routing protocol in order to handle wasted energy, congestion, and clustering. Wealso propose efficient routing and energy-efficient clustering algorithms based on optimization andgame theory. Furthermore, we propose a dynamic game theoretic framework (i.e., hyper defense)to analyze the interactions between attacker and defender as a non-cooperative security game thatconsiders the resource limitation. All the proposed schemes are validated by extensive experimentalanalyses, obtained by running simulations depicting various situations in WSNs in orderto represent real-world scenarios as realistically as possible. The results show that the proposedschemes achieve high performance in different terms, such as network lifetime, compared with thestate-of-the-art schemes.
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Date Issued
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2018
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Identifier
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CFE0006971, ucf:51672
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0006971
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Title
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Managing Effective Collaboration among Law Enforcement, Intelligence Services, and Military Forces in Fight against Terrorism and Organized Crime.
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Creator
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Demirhan, Cihan, Kapucu, Naim, Hu, Qian, Feldheim, Mary Ann, Rivera, Fernando, University of Central Florida
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Abstract / Description
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The fight against terrorism and organized crime require strong collaboration between public security organizations. Public security networks include several agencies that are not bound to each other with strong hierarchical ties. Because of a lack of the strong hierarchical structure, managing public networks is not similar to managing a single government agency. This study aims to examine the factors influencing network effectiveness in the public security sector. The main research questions...
Show moreThe fight against terrorism and organized crime require strong collaboration between public security organizations. Public security networks include several agencies that are not bound to each other with strong hierarchical ties. Because of a lack of the strong hierarchical structure, managing public networks is not similar to managing a single government agency. This study aims to examine the factors influencing network effectiveness in the public security sector. The main research questions of the study are: Which factors are important for effectiveness in public security networks? What is the role of inter-organizational trust among partner agencies? Which kind of leadership style will achieve the highest performance in public security networks? What is the relative importance of goal convergence and organizational culture in network effectiveness? How does the relationship between inter-organizational trust, leadership style, goal convergence and organizational culture impact network effectiveness? In order to find these relations, a self-reported survey was sent to 2,095 current and previous Turkish public security network managers. The study found that inter-organizational trust and goal convergence have a positive relationship with network effectiveness. Although facilitator leadership is found to be the most common leadership style in Turkish public security networks, it is found as inappropriate to achieve higher network effectiveness. According to the results, the co-producer network leadership is the most convenient leadership style in terms of network effectiveness. While the results of the descriptive statistics confirm that six specific features of organizational culture in public security sector have negative influence on network effectiveness, the hypothesis testing with the covariance structure model only support the negative impact of competition among partner organization. This study contributes to the literature on network effectiveness with particular proposals for the public security managers and practitioners.
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Date Issued
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2014
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Identifier
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CFE0005479, ucf:50350
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0005479
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Title
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Principals' Perceptions and Self-efficacy in Relation to School Security.
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Creator
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Jones, Julian, Taylor, Rosemarye, Doherty, Walter, Kennedy, Mary, Wolf, Ross, University of Central Florida
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Abstract / Description
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Principals in the nation's schools have been tasked with managing crisis incidents that may occur with students and others on their campuses on a daily basis. The purposes of this study were to determine the differences, if any, that existed in Central Florida public school principals' perceptions regarding school security, their perceived confidence to address critical crisis incidents on their campuses, their perceptions of the likelihood critical incidents would occur, their perceptions of...
Show morePrincipals in the nation's schools have been tasked with managing crisis incidents that may occur with students and others on their campuses on a daily basis. The purposes of this study were to determine the differences, if any, that existed in Central Florida public school principals' perceptions regarding school security, their perceived confidence to address critical crisis incidents on their campuses, their perceptions of the likelihood critical incidents would occur, their perceptions of interaction with law enforcement, the critical incidents they fear the most, and their perceptions of factors impacting the incidents they fear the most. Principal subgroup mean responses to the Principal Safety and Security Perceptions Survey in the three areas of Bandura's (1997) triadic reciprocal causation were examined in the context of principals' gender, longevity, student enrollment, grade configuration, free and reduced lunch rate, presence of a law enforcement officer, and presence of a security plan. Findings revealed significant differences between categorical groups of principals in multiple areas. It was determined that significant differences in principals' perceptions warrant further study. Recommendations for practice include security policy development and practical application of noted trends.
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Date Issued
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2015
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Identifier
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CFE0005636, ucf:50217
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0005636
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Title
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SAUDI ARABIA AND EXPANSIONIST WAHHABISM.
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Creator
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Baroni, Samiah, Handberg, Roger, University of Central Florida
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Abstract / Description
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This thesis examines the development of Wahhabism as an ideology into a rapidly expanding, transportable, contemporary Islamic political system. Serving as the territorial foundation, individuals maintain allegiance to Makkah, the center of the Islamic world, through symbolic Islamic prayer. Along with a central, globally financed economic distributive mechanism, and Wahhabi social and educational institutions emerging from the traditional mosque, Wahhabism serves the demand for an Islamic...
Show moreThis thesis examines the development of Wahhabism as an ideology into a rapidly expanding, transportable, contemporary Islamic political system. Serving as the territorial foundation, individuals maintain allegiance to Makkah, the center of the Islamic world, through symbolic Islamic prayer. Along with a central, globally financed economic distributive mechanism, and Wahhabi social and educational institutions emerging from the traditional mosque, Wahhabism serves the demand for an Islamic political system in a late capitalist world. Wahhabism is fluid within contemporary dynamic political systems and rapidly changing international relations. Wahhabism continues to expand at a global level, at times, providing a foundation for new forms of contemporary terrorism.
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Date Issued
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2006
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Identifier
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CFE0001005, ucf:46838
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0001005
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Title
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Networking and security solutions for VANET initial deployment stage.
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Creator
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Aslam, Baber, Zou, Changchun, Turgut, Damla, Bassiouni, Mostafa, Wang, Chung-Ching, University of Central Florida
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Abstract / Description
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Vehicular ad hoc network (VANET) is a special case of mobile networks, where vehicles equipped with computing/communicating devices (called (")smart vehicles(")) are the mobile wireless nodes. However, the movement pattern of these mobile wireless nodes is no more random, as in case of mobile networks, rather it is restricted to roads and streets. Vehicular networks have hybrid architecture; it is a combination of both infrastructure and infrastructure-less architectures. The direct vehicle...
Show moreVehicular ad hoc network (VANET) is a special case of mobile networks, where vehicles equipped with computing/communicating devices (called (")smart vehicles(")) are the mobile wireless nodes. However, the movement pattern of these mobile wireless nodes is no more random, as in case of mobile networks, rather it is restricted to roads and streets. Vehicular networks have hybrid architecture; it is a combination of both infrastructure and infrastructure-less architectures. The direct vehicle to vehicle (V2V) communication is infrastructure-less or ad hoc in nature. Here the vehicles traveling within communication range of each other form an ad hoc network. On the other hand, the vehicle to infrastructure (V2I) communication has infrastructure architecture where vehicles connect to access points deployed along roads. These access points are known as road side units (RSUs) and vehicles communicate with other vehicles/wired nodes through these RSUs. To provide various services to vehicles, RSUs are generally connected to each other and to the Internet. The direct RSU to RSU communication is also referred as I2I communication. The success of VANET depends on the existence of pervasive roadside infrastructure and sufficient number of smart vehicles. Most VANET applications and services are based on either one or both of these requirements. A fully matured VANET will have pervasive roadside network and enough vehicle density to enable VANET applications. However, the initial deployment stage of VANET will be characterized by the lack of pervasive roadside infrastructure and low market penetration of smart vehicles. It will be economically infeasible to initially install a pervasive and fully networked roadside infrastructure, which could result in the failure of applications and services that depend on V2I or I2I communications. Further, low market penetration means there are insufficient number of smart vehicles to enable V2V communication, which could result in failure of services and applications that depend on V2V communications. Non-availability of pervasive connectivity to certification authorities and dynamic locations of each vehicle will make it difficult and expensive to implement security solutions that are based on some central certificate management authority. Non-availability of pervasive connectivity will also affect the backend connectivity of vehicles to the Internet or the rest of the world. Due to economic considerations, the installation of roadside infrastructure will take a long time and will be incremental thus resulting in a heterogeneous infrastructure with non-consistent capabilities. Similarly, smart vehicles will also have varying degree of capabilities. This will result in failure of applications and services that have very strict requirements on V2I or V2V communications. We have proposed several solutions to overcome the challenges described above that will be faced during the initial deployment stage of VANET. Specifically, we have proposed: 1) a VANET architecture that can provide services with limited number of heterogeneous roadside units and smart vehicles with varying capabilities, 2) a backend connectivity solution that provides connectivity between the Internet and smart vehicles without requiring pervasive roadside infrastructure or large number of smart vehicles, 3) a security architecture that does not depend on pervasive roadside infrastructure or a fully connected V2V network and fulfills all the security requirements, and 4) optimization solutions for placement of a limited number of RSUs within a given area to provide best possible service to smart vehicles. The optimal placement solutions cover both urban areas and highways environments.
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Date Issued
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2012
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Identifier
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CFE0004186, ucf:48993
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0004186
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Title
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ARCHITECTURAL SUPPORT FOR IMPROVING COMPUTER SECURITY.
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Creator
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Kong, Jingfei, Zhou, Huiyang, University of Central Florida
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Abstract / Description
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Computer security and privacy are becoming extremely important nowadays. The task of protecting computer systems from malicious attacks and potential subsequent catastrophic losses is, however, challenged by the ever increasing complexity and size of modern hardware and software design. We propose several methods to improve computer security and privacy from architectural point of view. They provide strong protection as well as performance efficiency. In our first approach, we propose a new...
Show moreComputer security and privacy are becoming extremely important nowadays. The task of protecting computer systems from malicious attacks and potential subsequent catastrophic losses is, however, challenged by the ever increasing complexity and size of modern hardware and software design. We propose several methods to improve computer security and privacy from architectural point of view. They provide strong protection as well as performance efficiency. In our first approach, we propose a new dynamic information flow method to protect systems from popular software attacks such as buffer overflow and format string attacks. In our second approach, we propose to deploy encryption schemes to protect the privacy of an emerging non-volatile main memory technology ÃÂ phase change memory (PCM). The negative impact of the encryption schemes on PCM lifetime is evaluated and new methods including a new encryption counter scheme and an efficient error correct code (ECC) management are proposed to improve PCM lifetime. In our third approach, we deconstruct two previously proposed secure cache designs against software data-cache-based side channel attacks and demonstrate their weaknesses. We propose three hardware-software integrated approaches as secure protections against those data cache attacks. Also we propose to apply them to protect instruction caches from similar threats. Furthermore, we propose a simple change to the update policy of Branch Target Buffer (BTB) to defend against BTB attacks. Our experiments show that our proposed schemes are both security effective and performance efficient.
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Date Issued
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2010
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Identifier
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CFE0003211, ucf:48589
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0003211
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Title
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Effects of Signal Probability on Multitasking-Based Distraction in Driving, Cyberattack (&) Battlefield Simulation.
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Creator
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Sawyer, Benjamin, Karwowski, Waldemar, Hancock, Peter, Xanthopoulos, Petros, University of Central Florida
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Abstract / Description
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Multitasking-based failures of perception and action are the focus of much research in driving, where they are attributed to distraction. Similar failures occur in contexts where the construct of distraction is little used. Such narrow application was attributed to methodology which cannot precisely account for experimental variables in time and space, limiting distraction's conceptual portability to other contexts. An approach based upon vigilance methodology was forwarded as a solution, and...
Show moreMultitasking-based failures of perception and action are the focus of much research in driving, where they are attributed to distraction. Similar failures occur in contexts where the construct of distraction is little used. Such narrow application was attributed to methodology which cannot precisely account for experimental variables in time and space, limiting distraction's conceptual portability to other contexts. An approach based upon vigilance methodology was forwarded as a solution, and highlighted a fundamental human performance question: Would increasing the signal probability (SP) of a secondary task increase associated performance, as is seen in the prevalence effect associated with vigilance tasks? Would it reduce associated performance, as is seen in driving distraction tasks? A series of experiments weighed these competing assumptions. In the first, a psychophysical task, analysis of accuracy and response data revealed an interaction between the number of concurrent tasks and SP of presented targets. The question was further tested in the applied contexts of driving, cyberattack and battlefield target decision-making. In line with previous prevalence effect inquiry, presentation of stimuli at higher SP led to higher accuracy. In line with existing distraction work, performance of higher numbers of concurrent tasks tended to elicit slower response times. In all experiments raising either number of concurrent tasks or SP of targets resulted in greater subjective workload, as measured by the NASA TLX, even when accompanied by improved accuracy. It would seem that (")distraction(") in previous experiments has been an aggregate effect including both delayed response time and prevalence-based accuracy effects. These findings support the view that superior experimental control of SP reveals nomothetic patterns of performance that allow better understanding and wider application of the distraction construct both within and in diverse contexts beyond driving.
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Date Issued
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2015
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Identifier
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CFE0006388, ucf:51522
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0006388
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Title
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Quantifying Trust and Reputation for Defense against Adversaries in Multi-Channel Dynamic Spectrum Access Networks.
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Creator
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Bhattacharjee, Shameek, Chatterjee, Mainak, Guha, Ratan, Zou, Changchun, Turgut, Damla, Catbas, Necati, University of Central Florida
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Abstract / Description
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Dynamic spectrum access enabled by cognitive radio networks are envisioned to drivethe next generation wireless networks that can increase spectrum utility by opportunisticallyaccessing unused spectrum. Due to the policy constraint that there could be no interferenceto the primary (licensed) users, secondary cognitive radios have to continuously sense forprimary transmissions. Typically, sensing reports from multiple cognitive radios are fusedas stand-alone observations are prone to errors...
Show moreDynamic spectrum access enabled by cognitive radio networks are envisioned to drivethe next generation wireless networks that can increase spectrum utility by opportunisticallyaccessing unused spectrum. Due to the policy constraint that there could be no interferenceto the primary (licensed) users, secondary cognitive radios have to continuously sense forprimary transmissions. Typically, sensing reports from multiple cognitive radios are fusedas stand-alone observations are prone to errors due to wireless channel characteristics. Suchdependence on cooperative spectrum sensing is vulnerable to attacks such as SecondarySpectrum Data Falsification (SSDF) attacks when multiple malicious or selfish radios falsifythe spectrum reports. Hence, there is a need to quantify the trustworthiness of radios thatshare spectrum sensing reports and devise malicious node identification and robust fusionschemes that would lead to correct inference about spectrum usage.In this work, we propose an anomaly monitoring technique that can effectively cap-ture anomalies in the spectrum sensing reports shared by individual cognitive radios duringcooperative spectrum sensing in a multi-channel distributed network. Such anomalies areused as evidence to compute the trustworthiness of a radio by its neighbours. The proposedanomaly monitoring technique works for any density of malicious nodes and for any physicalenvironment. We propose an optimistic trust heuristic for a system with a normal risk attitude and show that it can be approximated as a beta distribution. For a more conservativesystem, we propose a multinomial Dirichlet distribution based conservative trust framework,where Josang's Belief model is used to resolve any uncertainty in information that mightarise during anomaly monitoring. Using a machine learning approach, we identify maliciousnodes with a high degree of certainty regardless of their aggressiveness and variations intro-duced by the pathloss environment. We also propose extensions to the anomaly monitoringtechnique that facilitate learning about strategies employed by malicious nodes and alsoutilize the misleading information they provide. We also devise strategies to defend against a collaborative SSDF attack that islaunched by a coalition of selfish nodes. Since, defense against such collaborative attacks isdifficult with popularly used voting based inference models or node centric isolation techniques, we propose a channel centric Bayesian inference approach that indicates how much the collective decision on a channels occupancy inference can be trusted. Based on the measured observations over time, we estimate the parameters of the hypothesis of anomalous andnon-anomalous events using a multinomial Bayesian based inference. We quantitatively define the trustworthiness of a channel inference as the difference between the posterior beliefsassociated with anomalous and non-anomalous events. The posterior beliefs are updated based on a weighted average of the prior information on the belief itself and the recently observed data.Subsequently, we propose robust fusion models which utilize the trusts of the nodes to improve the accuracy of the cooperative spectrum sensing decisions. In particular, we propose three fusion models: (i) optimistic trust based fusion, (ii) conservative trust based fusion, and (iii) inversion based fusion. The former two approaches exclude untrustworthy sensing reports for fusion, while the last approach utilizes misleading information. Allschemes are analyzed under various attack strategies. We propose an asymmetric weightedmoving average based trust management scheme that quickly identifies on-off SSDF attacks and prevents quick trust redemption when such nodes revert back to temporal honest behavior. We also provide insights on what attack strategies are more effective from the adversaries' perspective.Through extensive simulation experiments we show that the trust models are effective in identifying malicious nodes with a high degree of certainty under variety of network and radio conditions. We show high true negative detection rates even when multiple malicious nodes launch collaborative attacks which is an improvement over existing voting based exclusion and entropy divergence techniques. We also show that we are able to improve the accuracy of fusion decisions compared to other popular fusion techniques. Trust based fusion schemes show worst case decision error rates of 5% while inversion based fusion show 4% as opposed majority voting schemes that have 18% error rate. We also show that the proposed channel centric Bayesian inference based trust model is able to distinguish between attacked and non-attacked channels for both static and dynamic collaborative attacks. We are also able to show that attacked channels have significantly lower trust values than channels that are not(-) a metric that can be used by nodes to rank the quality of inference on channels.
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Date Issued
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2015
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Identifier
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CFE0005764, ucf:50081
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0005764
Pages