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End-to-End Security of Information Flow in Web-based ApplicationsSingaravelu, Lenin 25 June 2007 (has links)
Web-based applications and services are increasingly being used in security-sensitive tasks. Current security protocols rely on two crucial assumptions to protect the confidentiality and integrity of information: First, they assume that end-point software used to handle security-sensitive information is free from vulnerabilities. Secondly, these protocols assume point-to-point communication between a client and a service provider. However, these assumptions do not hold true with large and complex vulnerable end point software such as the Internet browser or web services middleware or in web service compositions where there can be multiple value-adding service providers interposed between a client and the original service provider.
To address the problem of large and complex end-point software, we present the AppCore approach which uses manual analysis of information flow, as opposed to purely automated approaches, to split existing software into two parts: a simplified trusted part that handles security-sensitive information and a legacy, untrusted part that handles non-sensitive information without access to sensitive information. Not only does this approach avoid many common and well-known vulnerabilities in the legacy software that compromised sensitive information, it also greatly reduces the size and complexity of the trusted code, thereby making exhaustive testing or formal analysis more feasible. We demonstrate the feasibility of the AppCore approach by constructing AppCores for two real-world applications: a client-side AppCore for https-based applications and an AppCore for web service platforms. Our evaluation shows that security improvements and complexity reductions (over a factor of five) can be attained with minimal modifications to existing software (a few tens of lines of code, and proxy settings of a browser) and an acceptable performance overhead (a few percent).
To protect the communication of sensitive information between the clients and service providers in web service compositions, we present an end-to-end security framework called WS-FESec that provides end-to-end security properties even in the presence of misbehaving intermediate services. We show that WS-FESec is flexible enough to support the lattice model of secure information flow and it guarantees precise security properties for each component service at a modest cost of a few milliseconds per signature or encrypted field.
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Implantação automatizada de composições de serviços web de grande escala / Automated deployment of large scale web service compositionsLeite, Leonardo Alexandre Ferreira 26 May 2014 (has links)
A implantação de composições de serviços web de grande escala apresentam vários desafios, tais como falhas corriqueiras na infraestrutura, heterogeneidade tecnológica, distribuição do sistema por diferentes organizações e atualização frequente dos serviços em operação. Nesta dissertação, estudamos como uma implantação automatizada baseada em middleware pode auxiliar na superação de tais desafios. Para isso, desenvolvemos o CHOReOS Enactment Engine, um sistema de middleware que possibilita a implantação distribuída e automatizada de composições de serviços web em uma infraestrutura virtualizada, operando no modelo de computação em nuvem denominado Plataforma como um Serviço. O middleware desenvolvido é avaliado qualitativamente em comparação a abordagens de implantação ad-hoc e quantitativamente pela sua escalabilidade em relação ao tempo de implantação das composições de serviços. / The deployment of large-scale service compositions presents several challenges, such as infrastructure failures, technological heterogeneity, distributions across different organizations, and continuous services updating. In this master thesis, we study how the automated deployed supported by middleware can help in overcoming such challenges. For this purpose, we developed the CHOReOS Enactment Engine, a middleware system that enables the distributed and automated deployment of web service compositions in a virtualized infrastructure, operating in the cloud computing model known as Platform as a Service. The developed middleware is evaluated qualitatively by comparing it with ad-hoc deployment solutions, and it is also evaluated quantitatively by its scalability regarding the deployment time of service compositions.
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Implantação automatizada de composições de serviços web de grande escala / Automated deployment of large scale web service compositionsLeonardo Alexandre Ferreira Leite 26 May 2014 (has links)
A implantação de composições de serviços web de grande escala apresentam vários desafios, tais como falhas corriqueiras na infraestrutura, heterogeneidade tecnológica, distribuição do sistema por diferentes organizações e atualização frequente dos serviços em operação. Nesta dissertação, estudamos como uma implantação automatizada baseada em middleware pode auxiliar na superação de tais desafios. Para isso, desenvolvemos o CHOReOS Enactment Engine, um sistema de middleware que possibilita a implantação distribuída e automatizada de composições de serviços web em uma infraestrutura virtualizada, operando no modelo de computação em nuvem denominado Plataforma como um Serviço. O middleware desenvolvido é avaliado qualitativamente em comparação a abordagens de implantação ad-hoc e quantitativamente pela sua escalabilidade em relação ao tempo de implantação das composições de serviços. / The deployment of large-scale service compositions presents several challenges, such as infrastructure failures, technological heterogeneity, distributions across different organizations, and continuous services updating. In this master thesis, we study how the automated deployed supported by middleware can help in overcoming such challenges. For this purpose, we developed the CHOReOS Enactment Engine, a middleware system that enables the distributed and automated deployment of web service compositions in a virtualized infrastructure, operating in the cloud computing model known as Platform as a Service. The developed middleware is evaluated qualitatively by comparing it with ad-hoc deployment solutions, and it is also evaluated quantitatively by its scalability regarding the deployment time of service compositions.
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Achieving Autonomic Web Service Compositions with Models at RuntimeAlférez Salinas, Germán Harvey 26 December 2013 (has links)
Over the last years, Web services have become increasingly popular. It is because they allow businesses to share data and business process (BP) logic through a programmatic interface across networks. In order to reach the full potential of
Web services, they can be combined to achieve specifi c functionalities.
Web services run in complex contexts where arising events may compromise the quality of the system (e.g. a sudden security attack). As a result, it is desirable to count on mechanisms to adapt Web service compositions (or simply
called service compositions) according to problematic events in the context. Since critical systems may require prompt responses, manual adaptations are unfeasible in large and intricate service compositions. Thus, it is suitable to
have autonomic mechanisms to guide their self-adaptation. One way to achieve this is by implementing variability constructs at the language level. However, this approach may become tedious, difficult to manage, and error-prone as the number of con figurations for the service composition grows.
The goal of this thesis is to provide a model-driven framework to guide autonomic adjustments of context-aware service compositions. This framework spans over design time and runtime to face arising known and unknown context events (i.e., foreseen and unforeseen at design time) in the close and open worlds respectively.
At design time, we propose a methodology for creating the models that guide autonomic changes. Since Service-Oriented Architecture (SOA) lacks support for systematic reuse of service operations, we represent service operations as Software Product Line (SPL) features in a variability model. As a result, our approach can support the construction of service composition families in mass production-environments. In order to reach optimum adaptations, the variability model and its possible con figurations are verifi ed at design time using Constraint Programming (CP).
At runtime, when problematic events arise in the context, the variability model is leveraged for guiding autonomic changes of the service composition. The activation and deactivation of features in the variability model result in changes in a composition model that abstracts the underlying service composition. Changes in the variability model are refl ected into the service composition by adding or removing fragments of Business Process Execution Language (WS-BPEL)
code, which are deployed at runtime. Model-driven strategies guide the safe migration of running service composition instances. Under the closed-world assumption, the possible context events are fully known at design time. These
events will eventually trigger the dynamic adaptation of the service composition. Nevertheless, it is diffi cult to foresee all the possible situations arising in uncertain contexts where service compositions run. Therefore, we extend our
framework to cover the dynamic evolution of service compositions to deal with unexpected events in the open world. If model adaptations cannot solve uncertainty, the supporting models self-evolve according to abstract tactics that
preserve expected requirements. / Alférez Salinas, GH. (2013). Achieving Autonomic Web Service Compositions with Models at Runtime [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/34672 / TESIS
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