1,144 research outputs found

    Using Open Stack for an Open Cloud Exchange(OCX)

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    We are developing a new public cloud, the Massachusetts Open Cloud (MOC) based on the model of an Open Cloud eXchange (OCX). We discuss in this paper the vision of an OCX and how we intend to realize it using the OpenStack open-source cloud platform in the MOC. A limited form of an OCX can be achieved today by layering new services on top of OpenStack. We have performed an analysis of OpenStack to determine the changes needed in order to fully realize the OCX model. We describe these proposed changes, which although significant and requiring broad community involvement will provide functionality of value to both existing single-provider clouds as well as future multi-provider ones

    On federated single sign-on in e-government interoperability frameworks

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    We consider the problem of handling digital identities within serviceoriented architecture (SOA) architectures. We explore federated, single signon (SSO) solutions based on identity managers and service providers. After an overview of the different standards and protocols, we introduce a middlewarebased architecture to simplify the integration of legacy systems within such platforms. Our solution is based on a middleware module that decouples the legacy system from the identity-management modules.We consider both standard point-to-point service architectures, and complex government interoperability frameworks, and report experiments to show that our solution provides clear advantages both in terms of effectiveness and performance

    A Service-Oriented Approach for Network-Centric Data Integration and Its Application to Maritime Surveillance

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    Maritime-surveillance operators still demand for an integrated maritime picture better supporting international coordination for their operations, as looked for in the European area. In this area, many data-integration efforts have been interpreted in the past as the problem of designing, building and maintaining huge centralized repositories. Current research activities are instead leveraging service-oriented principles to achieve more flexible and network-centric solutions to systems and data integration. In this direction, this article reports on the design of a SOA platform, the Service and Application Integration (SAI) system, targeting novel approaches for legacy data and systems integration in the maritime surveillance domain. We have developed a proof-of-concept of the main system capabilities to assess feasibility of our approach and to evaluate how the SAI middleware architecture can fit application requirements for dynamic data search, aggregation and delivery in the distributed maritime domain

    Grid Infrastructure for Domain Decomposition Methods in Computational ElectroMagnetics

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    The accurate and efficient solution of Maxwell's equation is the problem addressed by the scientific discipline called Computational ElectroMagnetics (CEM). Many macroscopic phenomena in a great number of fields are governed by this set of differential equations: electronic, geophysics, medical and biomedical technologies, virtual EM prototyping, besides the traditional antenna and propagation applications. Therefore, many efforts are focussed on the development of new and more efficient approach to solve Maxwell's equation. The interest in CEM applications is growing on. Several problems, hard to figure out few years ago, can now be easily addressed thanks to the reliability and flexibility of new technologies, together with the increased computational power. This technology evolution opens the possibility to address large and complex tasks. Many of these applications aim to simulate the electromagnetic behavior, for example in terms of input impedance and radiation pattern in antenna problems, or Radar Cross Section for scattering applications. Instead, problems, which solution requires high accuracy, need to implement full wave analysis techniques, e.g., virtual prototyping context, where the objective is to obtain reliable simulations in order to minimize measurement number, and as consequence their cost. Besides, other tasks require the analysis of complete structures (that include an high number of details) by directly simulating a CAD Model. This approach allows to relieve researcher of the burden of removing useless details, while maintaining the original complexity and taking into account all details. Unfortunately, this reduction implies: (a) high computational effort, due to the increased number of degrees of freedom, and (b) worsening of spectral properties of the linear system during complex analysis. The above considerations underline the needs to identify appropriate information technologies that ease solution achievement and fasten required elaborations. The authors analysis and expertise infer that Grid Computing techniques can be very useful to these purposes. Grids appear mainly in high performance computing environments. In this context, hundreds of off-the-shelf nodes are linked together and work in parallel to solve problems, that, previously, could be addressed sequentially or by using supercomputers. Grid Computing is a technique developed to elaborate enormous amounts of data and enables large-scale resource sharing to solve problem by exploiting distributed scenarios. The main advantage of Grid is due to parallel computing, indeed if a problem can be split in smaller tasks, that can be executed independently, its solution calculation fasten up considerably. To exploit this advantage, it is necessary to identify a technique able to split original electromagnetic task into a set of smaller subproblems. The Domain Decomposition (DD) technique, based on the block generation algorithm introduced in Matekovits et al. (2007) and Francavilla et al. (2011), perfectly addresses our requirements (see Section 3.4 for details). In this chapter, a Grid Computing infrastructure is presented. This architecture allows parallel block execution by distributing tasks to nodes that belong to the Grid. The set of nodes is composed by physical machines and virtualized ones. This feature enables great flexibility and increase available computational power. Furthermore, the presence of virtual nodes allows a full and efficient Grid usage, indeed the presented architecture can be used by different users that run different applications

    Semantic Integration of Identity Data Repositories

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    With the continuously growing number of distributed and heterogeneous IT systems there is the need for structured and efficient identity management (IdM) processes. This implies that new users are created once and then the information is distributed to all applicable software systems same as if changes on existing user objects occur. The central issue is that there is no generally ac-cepted standard for handling this information distribution because each system has its own internal representation of this data. Our approach is to give a se-mantic definition of the digital user objects attributes to ease the mapping process of an abstract user object to the concrete instantiation of each software system. Therefore we created an ontology to define the mapping of users at-tributes as well as an architecture which enables the semantic integration of identity data repositories. Our solution has been tested in an implementation case study

    Middleware Technologies for Cloud of Things - a survey

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    The next wave of communication and applications rely on the new services provided by Internet of Things which is becoming an important aspect in human and machines future. The IoT services are a key solution for providing smart environments in homes, buildings and cities. In the era of a massive number of connected things and objects with a high grow rate, several challenges have been raised such as management, aggregation and storage for big produced data. In order to tackle some of these issues, cloud computing emerged to IoT as Cloud of Things (CoT) which provides virtually unlimited cloud services to enhance the large scale IoT platforms. There are several factors to be considered in design and implementation of a CoT platform. One of the most important and challenging problems is the heterogeneity of different objects. This problem can be addressed by deploying suitable "Middleware". Middleware sits between things and applications that make a reliable platform for communication among things with different interfaces, operating systems, and architectures. The main aim of this paper is to study the middleware technologies for CoT. Toward this end, we first present the main features and characteristics of middlewares. Next we study different architecture styles and service domains. Then we presents several middlewares that are suitable for CoT based platforms and lastly a list of current challenges and issues in design of CoT based middlewares is discussed.Comment: http://www.sciencedirect.com/science/article/pii/S2352864817301268, Digital Communications and Networks, Elsevier (2017

    Middleware Technologies for Cloud of Things - a survey

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    The next wave of communication and applications rely on the new services provided by Internet of Things which is becoming an important aspect in human and machines future. The IoT services are a key solution for providing smart environments in homes, buildings and cities. In the era of a massive number of connected things and objects with a high grow rate, several challenges have been raised such as management, aggregation and storage for big produced data. In order to tackle some of these issues, cloud computing emerged to IoT as Cloud of Things (CoT) which provides virtually unlimited cloud services to enhance the large scale IoT platforms. There are several factors to be considered in design and implementation of a CoT platform. One of the most important and challenging problems is the heterogeneity of different objects. This problem can be addressed by deploying suitable "Middleware". Middleware sits between things and applications that make a reliable platform for communication among things with different interfaces, operating systems, and architectures. The main aim of this paper is to study the middleware technologies for CoT. Toward this end, we first present the main features and characteristics of middlewares. Next we study different architecture styles and service domains. Then we presents several middlewares that are suitable for CoT based platforms and lastly a list of current challenges and issues in design of CoT based middlewares is discussed.Comment: http://www.sciencedirect.com/science/article/pii/S2352864817301268, Digital Communications and Networks, Elsevier (2017

    Authorization Strategies for Grid Security: Attribute-Based Multipolicy Access Control (ABMAC) Model

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    The emergence of Grid computing technology is being followed by three main security concerns: the independence of the domains where the resource providers (RPs) are situated; the need for supporting different security policies andthe non-necessity of the science gateways for user authentication. Great effort has been involved in order to solve these concerns through the appearance of different access control models, like Identity-Based Authorization Control (IBAC) and Role-Based Authorization Control (RBAC), which based their access request decisionson user identity, that is, on user authentication. However, these models proved asinflexible, non-scalable and unmanageable in a distributed environment.Accordingly, a novel approach, known as Atrribute-Based MultipolicyAuthorization Control (ABMAC) model has appeared. ABMAC, which is beingdescribed in this paper, uses the attributes of the Grid entities for user authorization,based on the concepts of service-oriented architecture (SOA) and the eXtensibleMarkup Language (XML) standards - eXtensible Access Control Markup Language(XACML) and Security Assertion Markup Language (SAML). Moreover, ABMAChas been partly implemented in the Globus Toolkit 4 (GT4) Authorization Framework, and consequently it is expected to be outstanding contributor to Gridsecurity
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