2 research outputs found

    Securing open multi-agent systems governed by electronic institutions

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    One way to build large-scale autonomous systems is to develop an open multi-agent system using peer-to-peer architectures in which agents are not pre-engineered to work together and in which agents themselves determine the social norms that govern collective behaviour. The social norms and the agent interaction models can be described by Electronic Institutions such as those expressed in the Lightweight Coordination Calculus (LCC), a compact executable specification language based on logic programming and pi-calculus. Open multi-agent systems have experienced growing popularity in the multi-agent community and are expected to have many applications in the near future as large scale distributed systems become more widespread, e.g. in emergency response, electronic commerce and cloud computing. A major practical limitation to such systems is security, because the very openness of such systems opens the doors to adversaries for exploit existing vulnerabilities. This thesis addresses the security of open multi-agent systems governed by electronic institutions. First, the main forms of attack on open multi-agent systems are introduced and classified in the proposed attack taxonomy. Then, various security techniques from the literature are surveyed and analysed. These techniques are categorised as either prevention or detection approaches. Appropriate countermeasures to each class of attack are also suggested. A fundamental limitation of conventional security mechanisms (e.g. access control and encryption) is the inability to prevent information from being propagated. Focusing on information leakage in choreography systems using LCC, we then suggest two frameworks to detect insecure information flows: conceptual modeling of interaction models and language-based information flow analysis. A novel security-typed LCC language is proposed to address the latter approach. Both static (design-time) and dynamic (run-time) security type checking are employed to guarantee no information leakage can occur in annotated LCC interaction models. The proposed security type system is then formally evaluated by proving its properties. A limitation of both conceptual modeling and language-based frameworks is difficulty of formalising realistic policies using annotations. Finally, the proposed security-typed LCC is applied to a cloud computing configuration case study, in which virtual machine migration is managed. The secrecy of LCC interaction models for virtual machine management is analysed and information leaks are discussed

    Stand Up and Be Counted: Race, Religion, and the Eisenhower Administration's Encounter with Arab Nationalism

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    "Stand Up and be Counted" explores how American racial and religious beliefs guided the American encounter with Arab nationalism in the 1950s. It utilizes both traditional archival sources and less traditional cultural texts. Cultural texts, such as, movies, novels, travelogues, periodical articles, and folk sayings, are used to elucidate how Americans viewed and understood Arab peoples, and also religion. Archival records from the Dwight D. Eisenhower Presidential Library, National Archives, and John Foster Dulles Papers at Princeton University are used to elucidate how these beliefs shaped the Eisenhower administration‘s policy in the Middle East. The first chapter provided a brief introductory history of the Arab nationalist movement, reviews the literature, and introduces the dissertation's argument. The second chapter demonstrates that American culture established a canon of racialized beliefs about Arabs. These beliefs forged a national identity by constructing an Arab, to use Edward Said‘s famed term, "other." Americans to project what they believed they were not onto Arabs in an effort to establish what they were. The third chapter demonstrates that historical events caused subtle, yet important, shifts in how Americans perceived Arab peoples over the years. By focusing on the 1920s, 1940s, and 1950s "Stand Up and Be Counted" elucidates that historical events compelled specific racialized associations to assume greater prominence during these periods. The fourth chapter demonstrates that these racially filtered perceptions guided the Eisenhower administration's decision to oppose Arab nationalism. Arab nationalist leaders, such as Gamal Abdel Nasser of Egypt, advocated adopting a neutralist stance in the cold war. Administration officials, however, reasoned that Arabs' innate gullibility and irrationality would ultimately allow Soviet leaders to outwit and subjugate them—perhaps without them knowing it had even occurred. These racialized assumptions, the sixth chapter reveals, compelled the administration to labor to contain Arab nationalism, even after the combined British-French invasion of the Suez Canal. The seventh chapter establishes that many considered the United States to be a covenanted nation, a nation chosen by God to lead and save humanity. Beginning in the 1930s, however, many Americans came to fear that material secularism at home and abroad were threatening this mission. The monumental nature of these dual secularist threats prompted many to advocate for the formation of a united front of the religious. Among those who subscribed to this understanding were President Eisenhower and his Secretary of State John Foster Dulles. The eighth chapter established that this conceptualization of religion guided the administration's decision to promote King Saud of Saudi Arabia as a regional counter weight to Nasser and the Arab nationalist movement. The ninth chapter reveals that this strategy was fraught with peril
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