Security through Obscurity: Layout Obfuscation of Digital Integrated Circuits using Don't Care Conditions

Contemporary integrated circuits are designed and manufactured in a globalized environment leading to concerns of piracy, overproduction and counterfeiting. One class of techniques to combat these threats is circuit obfuscation which seeks to modify the gate-level (or structural) description of a circuit without affecting its functionality in order to increase the complexity and cost of reverse engineering. Most of the existing circuit obfuscation methods are based on the insertion of additional logic (called “key gates”) or camouflaging existing gates in order to make it difficult for a malicious user to get the complete layout information without extensive computations to determine key-gate values. However, when the netlist or the circuit layout, although camouflaged, is available to the attacker, he/she can use advanced logic analysis and circuit simulation tools and Boolean SAT solvers to reveal the unknown gate-level information without exhaustively trying all the input vectors, thus bringing down the complexity of reverse engineering. To counter this problem, some ‘provably secure’ logic encryption algorithms that emphasize methodical selection of camouflaged gates have been proposed previously in literature [1,2,3]. The contribution of this paper is the creation and simulation of a new layout obfuscation method that uses don't care conditions. We also present proof-of-concept of a new functional or logic obfuscation technique that not only conceals, but modifies the circuit functionality in addition to the gate-level description, and can be implemented automatically during the design process. Our layout obfuscation technique utilizes don’t care conditions (namely, Observability and Satisfiability Don’t Cares) inherent in the circuit to camouflage selected gates and modify sub-circuit functionality while meeting the overall circuit specification. Here, camouflaging or obfuscating a gate means replacing the candidate gate by a 4X1 Multiplexer which can be configured to perform all possible 2-input/ 1-output functions as proposed by Bao et al. [4]. It is important to emphasize that our approach not only obfuscates but alters sub-circuit level functionality in an attempt to make IP piracy difficult. The choice of gates to obfuscate determines the effort required to reverse engineer or brute force the design. As such, we propose a method of camouflaged gate selection based on the intersection of output logic cones. By choosing these candidate gates methodically, the complexity of reverse engineering can be made exponential, thus making it computationally very expensive to determine the true circuit functionality. We propose several heuristic algorithms to maximize the RE complexity based on don’t care based obfuscation and methodical gate selection. Thus, the goal of protecting the design IP from malicious end-users is achieved. It also makes it significantly harder for rogue elements in the supply chain to use, copy or replicate the same design with a different logic. We analyze the reverse engineering complexity by applying our obfuscation algorithm on ISCAS-85 benchmarks. Our experimental results indicate that significant reverse engineering complexity can be achieved at minimal design overhead (average area overhead for the proposed layout obfuscation methods is 5.51% and average delay overhead is about 7.732%). We discuss the strengths and limitations of our approach and suggest directions that may lead to improved logic encryption algorithms in the future. References: [1] R. Chakraborty and S. Bhunia, “HARPOON: An Obfuscation-Based SoC Design Methodology for Hardware Protection,” IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems, vol. 28, no. 10, pp. 1493–1502, 2009. [2] J. A. Roy, F. Koushanfar, and I. L. Markov, “EPIC: Ending Piracy of Integrated Circuits,” in 2008 Design, Automation and Test in Europe, 2008, pp. 1069–1074. [3] J. Rajendran, M. Sam, O. Sinanoglu, and R. Karri, “Security Analysis of Integrated Circuit Camouflaging,” ACM Conference on Computer Communications and Security, 2013. [4] Bao Liu, Wang, B., "Embedded reconfigurable logic for ASIC design obfuscation against supply chain attacks,"Design, Automation and Test in Europe Conference and Exhibition (DATE), 2014 , vol., no., pp.1,6, 24-28 March 2014.

Microblogging Temporal Summarization: Filtering Important Twitter Updates for Breaking News

While news stories are an important traditional medium to broadcast and consume news, microblogging has recently emerged as a place where people can dis- cuss, disseminate, collect or report information about news. However, the massive information in the microblogosphere makes it hard for readers to keep up with these real-time updates. This is especially a problem when it comes to breaking news, where people are more eager to know “what is happening”. Therefore, this dis- sertation is intended as an exploratory effort to investigate computational methods to augment human effort when monitoring the development of breaking news on a given topic from a microblog stream by extractively summarizing the updates in a timely manner. More specifically, given an interest in a topic, either entered as a query or presented as an initial news report, a microblog temporal summarization system is proposed to filter microblog posts from a stream with three primary concerns: topical relevance, novelty, and salience. Considering the relatively high arrival rate of microblog streams, a cascade framework consisting of three stages is proposed to progressively reduce quantity of posts. For each step in the cascade, this dissertation studies methods that improve over current baselines. In the relevance filtering stage, query and document expansion techniques are applied to mitigate sparsity and vocabulary mismatch issues. The use of word embedding as a basis for filtering is also explored, using unsupervised and supervised modeling to characterize lexical and semantic similarity. In the novelty filtering stage, several statistical ways of characterizing novelty are investigated and ensemble learning techniques are used to integrate results from these diverse techniques. These results are compared with a baseline clustering approach using both standard and delay-discounted measures. In the salience filtering stage, because of the real-time prediction requirement a method of learning verb phrase usage from past relevant news reports is used in conjunction with some standard measures for characterizing writing quality. Following a Cranfield-like evaluation paradigm, this dissertation includes a se- ries of experiments to evaluate the proposed methods for each step, and for the end- to-end system. New microblog novelty and salience judgments are created, building on existing relevance judgments from the TREC Microblog track. The results point to future research directions at the intersection of social media, computational jour- nalism, information retrieval, automatic summarization, and machine learning.

Humankindness: Illness, Animality, and the Limits of the Human in the Victorian Novel

This project posits a link between representations of animals or animality and representations of illness in the Victorian novel, and examines the narrative uses and ideological consequences of such representations. Figurations of animality and illness in Victorian fiction have been examined extensively as distinct phenomena, but examining their connection allows for a more complex view of the role of sympathy in the Victorian novel. The commonplace in novel criticism is that Victorian authors, whether effectively or not, constructed their novels with a view to the expansion of sympathy. This dissertation intervenes in the discussion of the Victorian novel as a vehicle for sympathy by positing that texts and scenes in which representations of illness and animality are conjoined reveal where the novel draws the boundaries of the human, and the often surprising limits it sets on sympathetic feeling. In such moments, textual cues train or direct readerly sympathies in ways that suggest a particular definition of the human, but that direction of sympathy is not always towards an enlarged sympathy, or an enlarged definition of the human. There is an equally (and increasingly) powerful antipathetic impulse in many of these texts, which estranges readerly sympathy from putatively deviant, degenerate, or dangerous groups. These two opposing impulses—the sympathetic and the antipathetic—often coexist in the same novel or even the same scene, creating an ideological and affective friction, and both draw on the same tropes of illness and animality. Examining the intersection of these different discourses—sympathy, illness, and animality-- in these novels reveals the way that major Victorian debates about human nature, evolution and degeneration, and moral responsibility shaped the novels of the era as vehicles for both antipathy and sympathy. Focusing on the novels of the Brontës and Thomas Hardy, this dissertation examines in depth the interconnected ways that representations of animals and animality and representations of illness function in the Victorian novel, as they allow authors to explore or redefine the boundary between the human and the non-human, the boundary between sympathy and antipathy, and the limits of sympathy itself.

Gospel Music Training, Performance Practice and Its Impact on Leadership Development and Performed Nationalism in a Collegiate Military Choir

Since America’s beginnings as a British colony, its musical standards have adhered to those of Western Europe. For this reason, musical forms native to America like Black folk spirituals and Gospel music have historically been marginalized in favor of music in the Western classical tradition. Today, a bias towards music of the Western classical tradition exists in those American universities that grant music degrees. While this bias is understandable, inclusion of Gospel music history and performance practice would result in a more complete understanding of American music and its impact on American nationalism. The United States Naval Academy is one of the few American universities that have consistently elevated the performance of Gospel music to the level of Western Classical music within its institutional culture. The motivations for writing this document are to provide a brief history of Gospel music in the United States and of choral music at the Naval Academy. These historical accounts serve as lenses though which the intersection of Gospel music performance practice and leadership development at the United States Naval Academy may be observed. During the last two decades of the twentieth century, Gospel music intersected American military culture at the U.S. Naval Academy. After a few student-led attempts in the 1970s, a Gospel Choir was formed in 1986 but by 1990, it had become an official part of the Music Department. Ultimately, it received institutional support and today, the Gospel Choir is one of three touring choirs authorized to represent the Academy in an official capacity. This document discusses the promotion of Gospel music by the Naval Academy in its efforts to diversify Academy culture and ultimately, Naval and Marine Corps leadership. Finally, this dissertation examines the addition of performed cultural expression (Gospel music) in light of a shift in American nationalism and discusses its impact on Naval Academy culture.

Intersections of Gay and Bisexual Identity with Fatness

This thesis examines the intersections of gay and bisexual identity with body size, or fatness. Gay and bisexual identity and fatness are marginalized social identities that seem to be incompatible (Bond, 2013). While a sense of collective identity with the gay and bisexual community has been shown to be a protective factor against internalized homonegativity in gay and bisexual men (Halpin & Allen, 2004), the degree to which this protective factor persists for fat people in an anti-fat environment like the gay and bisexual community (Wrench & Knapp, 2008) has not been explored. This intersection of identities and anti-fat culture seemed to suggest there might be a relationship between fatness and internalized homophobia. Fatness did not moderate the relationship between sense of belonging to the gay and bisexual community and internalized homonegativity, but a significant positive relationship was found between belongingness to the gay and bisexual community and body shame.

Green Circle

The speaker in this collection explores the quotidian experiences of daily life. Often restless, she attempts to find beauty or significance in these occurrences. The speaker looks into her personal history in a variety of locations. Many of the poems are set in Washington DC, California, Massachusetts and South Korea and as such, they explore the intersection of memory and present reality.

Reclaiming the Fall Zone: Mediating Physical and Cultural Exchange in Richmond, VA

This thesis will address cultural and physical place reclamation, at the ambiguous intersection of ‘city’ and nature.’ By creating a juxtaposed sequence of multi-scalar interventions, which challenge the conventional boundaries of architecture, and landscape architecture; in order to make commonplace a new dynamic threshold condition in Richmond, Virginia. At its core, this thesis is an attempt at place-making on a site which has become ‘no place.’ This concept will be manifest via a landscape park on Mayo Island in Richmond, anchored by a community retreat center, and architectural follies along a constructed path. The interventions will coincide with value of place in historical Richmond: an integrated, socially desegregated waterfront hinge; a social nexus of inherent change, at the point which the river itself changes at the fall line.

BLACK SURVIVAL POLITICS: ORGANIZED MOBILIZATION STRATEGIES IN AFRICAN AMERICAN COMMUNITIES TO END THE HIV/AIDS EPIDEMIC

The purpose of this study is to examine organizational patterns of African American activism in response the HIV/AIDS epidemic. Given their political, economic, and social disenfranchisement, African Americans have historically developed protest and survival strategies to respond to the devaluation of their lives, health, and well-being. While Black protest strategies are typically regarded as oppositional and transformative, Black survival strategies have generally been conceptualized as accepting inequality. In the case of HIV/AIDS, African American religious and non-religious organizations were less likely to deploy protest strategies to ensure the survival and well-being of groups most at risk for HIV/AIDS—such as African American gay men and substance abusers. This study employs a multiple qualitative case study analysis of four African American organizations that were among the early mobilizers to respond to HIV/AIDS in Washington D.C. These organizations include two secular or community-based organizations and two Black churches or faith-based organizations. Given the association of HIV/AIDS with sexual sin and social deviance, I postulated that Black community-based organizations would be more responsive to the HIV/AIDS-related needs and interests of African Americans than their religious counterparts. More specifically, I expected that Black churches would be more conservative (i.e. maintain paternalistic heteronormative sexual standards) than the community-based organizations. Yet findings indicate that the Black churches in this study were more similar than different than the community-based organizations in their strategic responses to HIV/AIDS. Both the community-based organizations and Black churches drew upon three main strategies in ways that politicalize the struggle for Black survival—or what I regard as Black survival politics. First, Black survival strategies for HIV/AIDS include coalition building at the intersection of multiple systems of inequality, as well as on the levels of identity and community. Second, Black survival politics include altering aspects of religious norms and practices related to sex and sexuality. Third, Black survival politics relies on the resources of the government to provide HIV/AIDS related programs and initiatives that are, in large part, based on the gains made from collective action.

Language-based Techniques for Practical and Trustworthy Secure Multi-party Computations

Secure Multi-party Computation (MPC) enables a set of parties to collaboratively compute, using cryptographic protocols, a function over their private data in a way that the participants do not see each other's data, they only see the final output. Typical MPC examples include statistical computations over joint private data, private set intersection, and auctions. While these applications are examples of monolithic MPC, richer MPC applications move between "normal" (i.e., per-party local) and "secure" (i.e., joint, multi-party secure) modes repeatedly, resulting overall in mixed-mode computations. For example, we might use MPC to implement the role of the dealer in a game of mental poker -- the game will be divided into rounds of local decision-making (e.g. bidding) and joint interaction (e.g. dealing). Mixed-mode computations are also used to improve performance over monolithic secure computations. Starting with the Fairplay project, several MPC frameworks have been proposed in the last decade to help programmers write MPC applications in a high-level language, while the toolchain manages the low-level details. However, these frameworks are either not expressive enough to allow writing mixed-mode applications or lack formal specification, and reasoning capabilities, thereby diminishing the parties' trust in such tools, and the programs written using them. Furthermore, none of the frameworks provides a verified toolchain to run the MPC programs, leaving the potential of security holes that can compromise the privacy of parties' data. This dissertation presents language-based techniques to make MPC more practical and trustworthy. First, it presents the design and implementation of a new MPC Domain Specific Language, called Wysteria, for writing rich mixed-mode MPC applications. Wysteria provides several benefits over previous languages, including a conceptual single thread of control, generic support for more than two parties, high-level abstractions for secret shares, and a fully formalized type system and operational semantics. Using Wysteria, we have implemented several MPC applications, including, for the first time, a card dealing application. The dissertation next presents Wys*, an embedding of Wysteria in F*, a full-featured verification oriented programming language. Wys* improves on Wysteria along three lines: (a) It enables programmers to formally verify the correctness and security properties of their programs. As far as we know, Wys* is the first language to provide verification capabilities for MPC programs. (b) It provides a partially verified toolchain to run MPC programs, and finally (c) It enables the MPC programs to use, with no extra effort, standard language constructs from the host language F*, thereby making it more usable and scalable. Finally, the dissertation develops static analyses that help optimize monolithic MPC programs into mixed-mode MPC programs, while providing similar privacy guarantees as the monolithic versions.

The Demobilized Body: Transgressions of Personal Space and Political Participation

Grounded in the intersection between gender politics and electoral studies, this dissertation examines the demobilizing effects of violations of personal space (in the form of domestic violence, control over mobility, emotional abuse, and sexual harassment) on the propensity to vote. Using quantitative methods across four survey datasets concerning Lebanon, the United States, Morocco, and Yemen, this research concludes that cross-regionally, familial control over mobility reduces the propensity to vote among women. Conversely, mechanisms of empowerment such as education and employment increase the propensity to vote.

Contested Play and Clean Water: McMillan Park, Race, and the Built Environment in Washington, D.C., 1900-1941

This study focuses on the intersection of the politics and culture of open public space with race relations in the United States from 1900 to 1941. The history of McMillan Park in Washington, D.C. serves as a lens to examine these themes. Ultimately, the park’s history, as documented in newspapers, interviews, reports, and photographs, reveals how white residents attempted to protect their dominance in a racial hierarchy through the control of both the physical and cultural elements of public recreation space. White use of discrimination through seemingly neutral desires to protect health, safety, and property values, establishes a congruence with their defense of residential property. Without similar access to legal methods, African Americans acted through direct action in gaps of governmental control. Their use of this space demonstrates how African-American residents of Washington and the United States contested their race, recreation, and spatial privileges in the pre-World War II era.

Development of Planning And Evaluation Models For Superstreets

Despite the extensive implementation of Superstreets on congested arterials, reliable methodologies for such designs remain unavailable. The purpose of this research is to fill the information gap by offering reliable tools to assist traffic professionals in the design of Superstreets with and without signal control. The entire tool developed in this thesis consists of three models. The first model is used to determine the minimum U-turn offset length for an Un-signalized Superstreet, given the arterial headway distribution of the traffic flows and the distribution of critical gaps among drivers. The second model is designed to estimate the queue size and its variation on each critical link in a signalized Superstreet, based on the given signal plan and the range of observed volumes. Recognizing that the operational performance of a Superstreet cannot be achieved without an effective signal plan, the third model is developed to produce a signal optimization method that can generate progression offsets for heavy arterial flows moving into and out of such an intersection design.