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You searched for subject:(Access Control Modelling). Showing records 1 – 3 of 3 total matches.

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University of Oxford

1. Slaymaker, Mark Arthur. The formalisation and transformation of access control policies.

Degree: PhD, 2011, University of Oxford

Increasing amounts of data are being collected and stored relating to every aspect of an individual's life, ranging from shopping habits to medical conditions. This data is increasingly being shared for a variety of reasons, from providing vast quantities of data to validate the latest medical hypothesis, to supporting companies in targeting advertising and promotions to individuals that fit a certain profile. In such cases, the data being used often comes from multiple sources  – with each of the contributing parties owning, and being legally responsible for, their own data. Within such models of collaboration, access control becomes important to each of the individual data owners. Although they wish to share data and benefit from information that others have provided, they do not wish to give away the entirety of their own data. Rather, they wish to use access control policies that give them control over which aspects of the data can be seen by particular individuals and groups. Each data owner will have access control policies that are carefully crafted and understood  – defined in terms of the access control representation that they use, which may be very different from the model of access control utilised by other data owners or by the technology facilitating the data sharing. Achieving interoperability in such circumstances would typically require the rewriting of the policies into a uniform or standard representation  – which may give rise to the need to embrace a new access control representation and/or the utilisation of a manual, error-prone, translation. In this thesis we propose an alternative approach, which embraces heterogeneity, and establishes a framework for automatic transformations of access control policies. This has the benefit of allowing data owners to continue to use their access control paradigm of choice. Of course, it is important that the data owners have some confidence in the fact that the new, transformed, access control policy representation accurately reflects their intentions. To this end, the use of tools for formal modelling and analysis allows us to reason about the translation, and demonstrate that the policies expressed in both representations are equivalent under access control requests; that is, for any given request both access control mechanisms will give an equivalent access decision. For the general case, we might propose a standard intermediate access control representation with transformations to and from each access control policy language of interest. However, for the purpose of this thesis, we have chosen to model the translation between role-based access control (RBAC) and the XML-based policy language, XACML, as a proof of concept of our approach. In addition to the formal models of the access control mechanisms and the translation, we provide, by way of a case study, an example of an implementation which performs the translation. The contributions of this thesis are as follows. First, we propose an approach to resolving issues of authorisation heterogeneity…

Subjects/Keywords: 621.382; Computer security; Computing; Software Engineering; Formal Methods; Access Control Modelling; Transformation

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Slaymaker, M. A. (2011). The formalisation and transformation of access control policies. (Doctoral Dissertation). University of Oxford. Retrieved from http://ora.ox.ac.uk/objects/uuid:179cd9d2-0547-42b7-84a0-690bc4478bfb ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.542973

Chicago Manual of Style (16th Edition):

Slaymaker, Mark Arthur. “The formalisation and transformation of access control policies.” 2011. Doctoral Dissertation, University of Oxford. Accessed January 24, 2021. http://ora.ox.ac.uk/objects/uuid:179cd9d2-0547-42b7-84a0-690bc4478bfb ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.542973.

MLA Handbook (7th Edition):

Slaymaker, Mark Arthur. “The formalisation and transformation of access control policies.” 2011. Web. 24 Jan 2021.

Vancouver:

Slaymaker MA. The formalisation and transformation of access control policies. [Internet] [Doctoral dissertation]. University of Oxford; 2011. [cited 2021 Jan 24]. Available from: http://ora.ox.ac.uk/objects/uuid:179cd9d2-0547-42b7-84a0-690bc4478bfb ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.542973.

Council of Science Editors:

Slaymaker MA. The formalisation and transformation of access control policies. [Doctoral Dissertation]. University of Oxford; 2011. Available from: http://ora.ox.ac.uk/objects/uuid:179cd9d2-0547-42b7-84a0-690bc4478bfb ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.542973


University of Rochester

2. Karaoglu, Bora. Efficient use of resources in mobile ad hoc networks.

Degree: PhD, 2014, University of Rochester

Efficient use of the resources in mobile ad hoc networks (MANETs) is of great importance to maintain the required quality of service and to prolong the network lifetime. The utilization of the resources such as bandwidth and energy depends on a number of conditions such as network size, node density, and load distribution. These conditions are uncontrollable and often vary throughout the operation of the network. In order to efficiently use the resources, the protocols that determine the behavior of the network should dynamically adapt to these changing conditions. My thesis is that a protocol architecture for MANETs that dynamically adapts to changing conditions based on cooperation and information sharing leads to more efficient use of the system resources compared to competition based architectures. In particular, in this dissertation we explore the benefits of adaptation based on cooperation and information sharing at the medium access control (MAC) and network (routing) layers of the protocol stack. At the MAC layer, we develop an analytical model that reflects the relationships between protocol parameters and the overall performance of the protocol under various network conditions. This model reveals that the protocol parameters at the MAC layer can be adjusted to make best use of the channel resources depending on the application requirements and network conditions obtained through information sharing, such as average network load density. In order to provide a dynamic system that adapts not only to changing conditions but also to spatially non-uniform traffic load distributions, a lightweight dynamic channel allocation algorithm and a cooperative load balancing algorithm that facilitate efficient use of resources based on local information sharing are proposed. Through extensive simulations, we show that both dynamic channel allocation and cooperative load balancing improve the bandwidth efficiency under non-uniform load distributions compared with protocols that do not use these mechanisms as well as compared with the IEEE 802.11 uncoordinated protocol. Properly routing the data over a MANET is another challenging topic due to the dynamic behavior of the network, yet it is also crucial in terms of efficient use of resources. Two important routing schemes, network-wide broadcasting and multicasting, are investigated for trade-os and merged into a single framework. The framework allows the selection of the optimal routing scheme based on the network conditions obtained through information sharing, leading to the best use of the system resources in terms of spectrum efficiency and energy efficiency. The interaction of a network with other networks coexisting at the same site also strongly determines its efficiency. We developed an approach for symbiotic networking using hybrid nodes, and our results clearly show that symbiotic networking can provide vital support to co-located networks, which is especially important in resource-constrained networks such as MANETs. Although…

Subjects/Keywords: Analytical modelling; Bandwidth efficiency; Energy efficient communications; Medium access control; Mobile ad hoc networks; Symbiotic networking

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Karaoglu, B. (2014). Efficient use of resources in mobile ad hoc networks. (Doctoral Dissertation). University of Rochester. Retrieved from http://hdl.handle.net/1802/28321

Chicago Manual of Style (16th Edition):

Karaoglu, Bora. “Efficient use of resources in mobile ad hoc networks.” 2014. Doctoral Dissertation, University of Rochester. Accessed January 24, 2021. http://hdl.handle.net/1802/28321.

MLA Handbook (7th Edition):

Karaoglu, Bora. “Efficient use of resources in mobile ad hoc networks.” 2014. Web. 24 Jan 2021.

Vancouver:

Karaoglu B. Efficient use of resources in mobile ad hoc networks. [Internet] [Doctoral dissertation]. University of Rochester; 2014. [cited 2021 Jan 24]. Available from: http://hdl.handle.net/1802/28321.

Council of Science Editors:

Karaoglu B. Efficient use of resources in mobile ad hoc networks. [Doctoral Dissertation]. University of Rochester; 2014. Available from: http://hdl.handle.net/1802/28321

3. Ueda, Eduardo Takeo. Análise de políticas de controle de acesso baseado em papéis com rede de Petri colorida.

Degree: PhD, Sistemas Digitais, 2012, University of São Paulo

Controle de acesso é um tópico de pesquisa importante tanto para a academia quanto para a indústria. Controle de Acesso Baseado em Papéis (CABP) foi desenvolvido no início dos anos 1990, tornando-se um padrão generalizado para controle de acesso em vários produtos e soluções computacionais. Embora modelos CABP sejam largamente aceitos e adotados, ainda existem questões para responder. Um dos principais desafios de pesquisa em segurança baseada em papéis é determinar se uma política de controle de acesso é consistente em um ambiente altamente dinâmico. Nossa pesquisa visa preencher essa lacuna fornecendo um método para analisar políticas CABP com respeito a dois aspectos significativos: segurança e dinamismo envolvendo papéis e objetos. Para este propósito, desenvolvemos um modelo de descrição e simulação de política usando rede de Petri colorida e CPN Tools. O modelo descreve e é capaz de simular vários estados CABP em um contexto de educação a distância típico. Usando este modelo, foi possível analisar o espaço de estados produzido pela rede de Petri colorida em um cenário dinâmico envolvendo a criação de novos papéis e objetos. O resultado da análise de alcançabilidade da rede de Petri da política demonstrou que é possível verificar a consistência de políticas de controle de acesso considerando a dinamicidade de papéis e objetos, e apontou vantagens de aplicabilidade da modelagem de políticas de segurança em ambientes distribuídos utilizando rede de Petri colorida.

Access control is an important research topic both for academia and industry. Role Based Access Control (RBAC) was developed in the early 1990s, becoming a generalized standard of access control for many products and computing solutions. Although RBAC models have been widely accepted and adopted, there are issues to answer. One of the key challenges for role-based security research is to characterize whether an access control policy is consistent in a highly dynamic environment. Our research aims filling this gap providing a method to analyze RBAC policies with respect to two significant aspects: security and dynamics involving roles and objects. For this purpose, we developed a policy description and simulation model using colored Petri net and the CPN Tools. The model describes and is capable to simulate many RBAC states in a typical distance education context. Using this model it was possible to analyze the state space provided by colored Petri net that simulates a dynamic environment and the creation of new roles and objects. The result of the reachability analysis of Petri net policy showed that it is possible to check the consistency of access control policies considering dynamic of roles and objects, and point out the advantages and applicability of modeling security policies in distributed environments using colored Petri net.

Advisors/Committee Members: Ruggiero, Wilson Vicente.

Subjects/Keywords: Colored Petri net; Controle de acesso baseado em papéis; Modelagem; Modelling; Políticas de segurança; Rede de Petri colorida; Role based access control; Security policies; Simulação; Simulation

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Ueda, E. T. (2012). Análise de políticas de controle de acesso baseado em papéis com rede de Petri colorida. (Doctoral Dissertation). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/3/3141/tde-08032013-120904/ ;

Chicago Manual of Style (16th Edition):

Ueda, Eduardo Takeo. “Análise de políticas de controle de acesso baseado em papéis com rede de Petri colorida.” 2012. Doctoral Dissertation, University of São Paulo. Accessed January 24, 2021. http://www.teses.usp.br/teses/disponiveis/3/3141/tde-08032013-120904/ ;.

MLA Handbook (7th Edition):

Ueda, Eduardo Takeo. “Análise de políticas de controle de acesso baseado em papéis com rede de Petri colorida.” 2012. Web. 24 Jan 2021.

Vancouver:

Ueda ET. Análise de políticas de controle de acesso baseado em papéis com rede de Petri colorida. [Internet] [Doctoral dissertation]. University of São Paulo; 2012. [cited 2021 Jan 24]. Available from: http://www.teses.usp.br/teses/disponiveis/3/3141/tde-08032013-120904/ ;.

Council of Science Editors:

Ueda ET. Análise de políticas de controle de acesso baseado em papéis com rede de Petri colorida. [Doctoral Dissertation]. University of São Paulo; 2012. Available from: http://www.teses.usp.br/teses/disponiveis/3/3141/tde-08032013-120904/ ;

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