2 resultados para endogenous coalition formation

em CORA - Cork Open Research Archive - University College Cork - Ireland


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Open environments involve distributed entities interacting with each other in an open manner. Many distributed entities are unknown to each other but need to collaborate and share resources in a secure fashion. Usually resource owners alone decide who is trusted to access their resources. Since resource owners in open environments do not have a complete picture of all trusted entities, trust management frameworks are used to ensure that only authorized entities will access requested resources. Every trust management system has limitations, and the limitations can be exploited by malicious entities. One vulnerability is due to the lack of globally unique interpretation for permission specifications. This limitation means that a malicious entity which receives a permission in one domain may misuse the permission in another domain via some deceptive but apparently authorized route; this malicious behaviour is called subterfuge. This thesis develops a secure approach, Subterfuge Safe Trust Management (SSTM), that prevents subterfuge by malicious entities. SSTM employs the Subterfuge Safe Authorization Language (SSAL) which uses the idea of a local permission with a globally unique interpretation (localPermission) to resolve the misinterpretation of permissions. We model and implement SSAL with an ontology-based approach, SSALO, which provides a generic representation for knowledge related to the SSAL-based security policy. SSALO enables integration of heterogeneous security policies which is useful for secure cooperation among principals in open environments where each principal may have a different security policy with different implementation. The other advantage of an ontology-based approach is the Open World Assumption, whereby reasoning over an existing security policy is easily extended to include further security policies that might be discovered in an open distributed environment. We add two extra SSAL rules to support dynamic coalition formation and secure cooperation among coalitions. Secure federation of cloud computing platforms and secure federation of XMPP servers are presented as case studies of SSTM. The results show that SSTM provides robust accountability for the use of permissions in federation. It is also shown that SSAL is a suitable policy language to express the subterfuge-safe policy statements due to its well-defined semantics, ease of use, and integrability.

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This dissertation critically examines Ireland’s knowledge economy policy, the country’s basis for economic recovery and growth, to enhance future policy decisions and debate. Much has been written internationally on the ‘knowledge economy’ with its emergence closely related to globalisation and technological progression in the 1990s. Since the late 1990s, Irish policy-makers have been firmly committed to positioning Ireland as a leading knowledge economy. Transforming the country’s competitive base to a knowledge economy is pivotal, directly shaping the course of Ireland’s economy and society. Given Ireland’s current economic crisis, limited resources, global competition from leaders in science and technology and growing challenges from emerging economies, a systematic study of Ireland’s major competitive policy is imperative. Above all, this study explores the processes behind the policy and the multiple actors from different institutions who follow and seek to influence decisions. The advocacy coalition framework is used to identify the advocacy coalition operating in the knowledge economy policy subsystem. The theoretical insights of this framework are also combined with other public policy approaches, providing complementary insights into the policy process. The research is framed around three elements - the beliefs underpinning the policy; who is driving the policy; and the prospects of the policy. Primary information is collected by way of semi-structured in-depth interviews with 49 Irish elites (politicians, senior bureaucrats, academics and business leaders) involved in the formation and implementation of the policy. This study finds that a strong advocacy coalition has formed in this policy subsystem whose members are collectively driving the policy. Both exogenous and endogenous forces help frame a common perception of the problems the policy addresses and the solutions it offers. Evidence suggests that this policy is a sustainable option for Ireland’s economic future and the study concludes with policy recommendations for advancing Ireland’s knowledge economy.