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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
841

Energy efficient resource allocation in cloud computing environments / Allocation des ressources efficaces en énergie dans les environnements Cloud

Ghribi, Chaima 22 December 2014 (has links)
L'informatique en nuage (Cloud Computing) a émergé comme un nouveau paradigme pour offrir des ressources informatiques à la demande et pour externaliser des infrastructures logicielles et matérielles. Le Cloud Computing est rapidement et fondamentalement en train de révolutionner la façon dont les services informatiques sont mis à disposition et gérés. Ces services peuvent être demandés à partir d'un ou plusieurs fournisseurs de Cloud d'où le besoin de la mise en réseau entre les composants des services informatiques distribués dans des emplacements géographiquement répartis. Les utilisateurs du Cloud veulent aussi déployer et instancier facilement leurs ressources entre les différentes plateformes hétérogènes de Cloud Computing. Les fournisseurs de Cloud assurent la mise à disposition des ressources de calcul sous forme des machines virtuelles à leurs utilisateurs. Par contre, ces clients veulent aussi la mise en réseau entre leurs ressources virtuelles. En plus, ils veulent non seulement contrôler et gérer leurs applications, mais aussi contrôler la connectivité réseau et déployer des fonctions et des services de réseaux complexes dans leurs infrastructures virtuelles dédiées. Les besoins des utilisateurs avaient évolué au-delà d'avoir une simple machine virtuelle à l'acquisition de ressources et de services virtuels complexes, flexibles, élastiques et intelligents. L'objectif de cette thèse est de permettre le placement et l'instanciation des ressources complexes dans des infrastructures de Cloud distribués tout en permettant aux utilisateurs le contrôle et la gestion de leurs ressources. En plus, notre objectif est d'assurer la convergence entre les services de cloud et de réseau. Pour atteindre ces objectifs, cette thèse propose des algorithmes de mapping d'infrastructures virtuelles dans les centres de données et dans le réseau tout en respectant les exigences des utilisateurs. Avec l'apparition du Cloud Computing, les réseaux traditionnels sont étendus et renforcés avec des réseaux logiciels reposant sur la virtualisation des ressources et des fonctions réseaux. En plus, le nouveau paradigme d'architecture réseau (SDN : Software Defined Networks) est particulièrement pertinent car il vise à offrir la programmation du réseau et à découpler, dans un équipement réseau, la partie plan de données de la partie plan de contrôle. Dans ce contexte, la première partie de la thèse propose des algorithmes optimaux (exacts) et heuristiques de placement pour trouver le meilleur mapping entre les demandes des utilisateurs et les infrastructures sous-jacentes, tout en respectant les exigences exprimées dans les demandes. Cela inclut des contraintes de localisation permettant de placer une partie des ressources virtuelles dans le même nœud physique. Ces contraintes assurent aussi le placement des ressources dans des nœuds distincts. Les algorithmes proposés assurent le placement simultané des nœuds et des liens virtuels sur l'infrastructure physique. Nous avons proposé aussi un algorithme heuristique afin d'accélérer le temps de résolution et de réduire la complexité du problème. L'approche proposée se base sur la technique de décomposition des graphes et la technique de couplage des graphes bipartis. Dans la troisième partie de la thèse, nous proposons un cadriciel open source (framework) permettant d'assurer la mise en réseau dynamique entre des ressources Cloud distribués et l'instanciation des fonctions réseau dans l'infrastructure virtuelle de l'utilisateur. Ce cadriciel permettra de déployer et d'activer les composants réseaux afin de mettre en place les demandes des utilisateurs. Cette solution se base sur un gestionnaire des ressources réseaux "Cloud Network Gateway Manager" et des passerelles logicielles permettant d'établir la connectivité dynamique et à la demande entre des ressources cloud et réseau [...] / Cloud computing has rapidly emerged as a successful paradigm for providing IT infrastructure, resources and services on a pay-per-use basis over the past few years. As, the wider adoption of Cloud and virtualization technologies has led to the establishment of large scale data centers that consume excessive energy and have significant carbon footprints, energy efficiency is becoming increasingly important for data centers and Cloud. Today data centers energy consumption represents 3 percent of all global electricity production and is estimated to further rise in the future. This thesis presents new models and algorithms for energy efficient resource allocation in Cloud data centers. The first goal of this work is to propose, develop and evaluate optimization algorithms of resource allocation for traditional Infrastructutre as a Service (IaaS) architectures. The approach is Virtual Machine (VM) based and enables on-demand and dynamic resource scheduling while reducing power consumption of the data center. This initial objective is extended to deal with the new trends in Cloud services through a new model and optimization algorithms of energy efficient resource allocation for hybrid IaaS-PaaS Cloud providers. The solution is generic enough to support different type of virtualization technologies, enables both on-demand and advanced resource provisioning to deal with dynamic resource scheduling and fill the gap between IaaS and PaaS services and create a single continuum of services for Cloud users. Consequently, in the thesis, we first present a survey of the state of the art on energy efficient resource allocation in cloud environments. Next, we propose a bin packing based approach for energy efficient resource allocation for classical IaaS. We formulate the problem of energy efficient resource allocation as a bin-packing model and propose an exact energy aware algorithm based on integer linear program (ILP) for initial resource allocation. To deal with dynamic resource consolidation, an exact ILP algorithm for dynamic VM reallocation is also proposed. This algorithm is based on VM migration and aims at constantly optimizing energy efficiency at service departures. A heuristic method based on the best-fit algorithm has also been adapted to the problem. Finally, we present a graph-coloring based approach for energy efficient resource allocation in the hybrid IaaS-PaaS providers context. This approach relies on a new graph coloring based model that supports both VM and container virtualization and provides on-demand as well as advanced resource reservation. We propose and develop an exact Pre-coloring algorithm for initial/static resource allocation while maximizing energy efficiency. A heuristic Pre-coloring algorithm for initial resource allocation is also proposed to scale with problem size. To adapt reservations over time and improve further energy efficiency, we introduce two heuristic Re-coloring algorithms for dynamic resource reallocation. Our solutions are generic, robust and flexible and the experimental evaluation shows that both proposed approaches lead to significant energy savings while meeting the users' requirements
842

VISUELL PRESENTATION AV VÄDERDATA OCH ELPRISERE TT ARBETE OM DATABASMODELLERING I MOLNET MED BUSINESS INTELLIGENCE

Björnbom, Willie, Eklöf, Alexander January 2019 (has links)
In an environment where data flows everywhere and in all forms, it can be difficult to extract something valuable of it. Business Intelligence, also known as BI, is a technology used to transform information into a valuable resource for primarily companies with a lot of information. But what opportunities does BI offer? In this essay, we use standardized techniques, popular tools and cloud services to perform a pure BI project. We will generate a report in which we will analyze whether there is any correlation between electricity prices and different types of weather data. After the practical part of the work, we will use our experience of the cloud to dig deeper into how safe the cloud reallys is. We will compare the concerns that an ordinary user has to the cloud and compare with how the cloud service provider (CSP) Azure adapts to this. / ett samhälle där information flödar i alla dess former så kan det vara svårt att utvinna någontingvärdefullt av detta. Business intelligence, även kallat BI, är en teknik som används för att kunnaomvandla informationen till en värdefull resurs för främst företag. Men vad kan man egentligengöra med BI? I denna uppsats används standardiserade tekniker, nya verktyg och molntjänster föratt utföra ett helt BI-projekt. Projektet innefattar en visuell rapport där det ska göras en grundliganalys om det finns någon korrelation mellan elpriser och olika typer av väderdata.Efter det praktiska arbetet så kommer en teoretiskt fördjupning inom molntjärnes säkerhet attutföras. Den teoretiska fördjupningen kommer att omfatta en jämförelse mellan de mestförekommande orosmoment som användare har inför molnet och hur Azure faktiskt ställer sig tilldessa.
843

Adoption of Cloud Computing Services in an Illinois-Based Insurance Company

Polk, Nekerral 01 January 2019 (has links)
The decision to adopt cloud computing services should involve business units of an insurance company as well as information technology (IT) because cloud computing services are viewed as both a technology offering and business alternative. The purpose of this qualitative exploratory case study was to explore the strategies used by IT architects of an Illinois-based insurance company when adopting cloud computing services. The theory supporting this study was the technology acceptance model. The study's population consisted of IT architects from an Illinois-based insurance company that have used strategies to adopt cloud computing services. This study's data collection included semistructured interviews and review of organizational documents. Member checking with each participant increased the validity of this study's findings. Four major themes emerged from this study: strategies to adopt cloud computing services, strategies to adopt cloud services models, strategies to adopt cloud computing models, and concerns affecting the strategies to adopt cloud computing services. The study findings may assist IT architects in developing effective strategies to adopt cloud computing services for their respective business unit. This study might serve as a foundation for positive social change by decreasing customer concerns regarding critical information being compromised when adopting cloud computing services.
844

Aligning Social Media, Mobile, Analytics, and Cloud Computing Technologies and Disaster Response

Worthy, William Tuley 01 January 2018 (has links)
After nearly 2 decades of advances in information and communications technologies (ICT) including social media, mobile, analytics, and cloud computing, disaster response agencies in the United States have not been able to improve alignment between ICT-based information and disaster response actions. This grounded theory study explored emergency response ICT managers' understanding of how social media, mobile, analytics, and cloud computing technologies (SMAC) are related to and can inform disaster response strategies. Sociotechnical theory served as the conceptual framework to ground the study. Data were collected from document reviews and semistructured interviews with 9 ICT managers from emergency management agencies in the state of Hawaii who had experience in responding to major disasters. The data were analyzed using open, axial coding, and selective coding. Three elements of a theory emerged from the findings: (a) the ICT managers were hesitant about SMAC technologies replacing first responder's radios to interoperate between emergency response agencies during major disasters, (b) the ICT managers were receptive to converging conventional ICT with SMAC technologies, and (c) the ICT managers were receptive to joining legacy information sharing strategies with new information sharing strategies based on SMAC technologies. The emergent theory offers a framework for aligning SMAC technologies and disaster response strategies. The implications for positive social change include reduced interoperability failures between disaster agencies during major catastrophes, which may lower the risk of casualties and deaths to emergency responders and disaster victims, thus benefiting them and their communities.
845

A Pattern Language for Designing Application-Level Communication Protocols and the Improvement of Computer Science Education through Cloud Computing

Lascano, Jorge Edison 01 May 2017 (has links)
Networking protocols have been developed throughout time following layered architectures such as the Open Systems Interconnection model and the Internet model. These protocols are grouped in the Internet protocol suite. Most developers do not deal with low-level protocols, instead they design application-level protocols on top of the low-level protocol. Although each application-level protocol is different, there is commonality among them and developers can apply lessons learned from one protocol to the design of new ones. Design patterns can help by gathering and sharing proven and reusable solution to common, reoccurring design problems. The Application-level Communication Protocols Design Patterns language captures this knowledge about application-level protocol design, so developers can create better, more fitting protocols base on these common and well proven solutions. Another aspect of contemporary development technics is the need of distribution of software artifacts. Most of the development companies have started using Cloud Computing services to overcome this need; either public or private clouds are widely used. Future developers need to manage this technology infrastructure, software, and platform as services. These two aspects, communication protocols design and cloud computing represent an opportunity to contribute to the software development community and to the software engineering education curriculum. The Application-level Communication Protocols Design Patterns language aims to help solve communication software design. The use of cloud computing in programming assignments targets on a positive influence on improving the Analysis to Reuse skills of students of computer science careers.
846

Factors That Contribute to The Resistance to Cloud Computing Adoption by Tech Companies vs. Non-Tech Companies

Hakim, Zadok 01 January 2018 (has links)
Cloud computing (CC) may be the most significant development in recent history for businesses seeking to utilize technology. However, the adoption of CC hinges on many factors, and can have a greater positive impact on organizational performance. This study examined the different factors that contribute to the resistance to CC adoption. Anchored in The Theory of Technology-Organization-Environment (TOE), the study used a qualitative, grounded theory approach to develop a theoretical model for the acceptance of CC across firms. CC can have significant effects on efficiency and productivity for firms, but these effects will only be realized if IT usage becomes utilized globally. Thus, it was essential to understand the determinants of IT adoption, which was the goal of this research. The central research question involved understanding and examining the factors of resistance that contribute to cloud computing adoption across firms. Data was collected through semi-structured interviews with 22 chief information officers (CIOs) of various firms, including those considered technology companies (TCs) and those considered non-technology companies (NTCs). Data was analyzed using qualitative thematic analysis to determine what factors influence the adoption of CC systems and, moreover, to determine what factors create resistance to the adoption of CC in firms despite its well-documented advantages and benefits. Additionally, by examinging and focusing on the factors of resistance, the rsults of this study were generalized across a wider array of firms located in the Southeastern region of the US. A total of 12 categories were identified. These were organized into two groups. The core category being financial risks represented the probability of loss inherent in financing methods which may impair the ability to provide adequate return. The categories lack of knowledge, resistance to change, excessive cost to adopt, and cost saving fit under financial risks. Together these categories were indicators of the factors of resistance to adopt cloud computing technology. The core category security risks represented the overall perception of privacy in online environment. The categories process of research, accessing organization fit, perceived security risks, phased deployment, approval to adopt, and increase flexibility fit under security risks. Together these categories were direct indicators of the factors of resistance that contribute to the adoption of cloud computing technology by both TC and NTC. The result of this study showed that the predominant and critical factors of resistance that contribute to cloud computing adoption by TC were financial risks and security risks vs. security risks by NTC. A critical distinction between TC and NTC is that 86.4% of NTC’s participants did not care about cost, they only cared about data security. A model was subsequently developed based on the lived experiences of Chief Information Officers (CIOs) who have been faced with challenges regarding cloud acceptance, and cloud computing adoption. The theoretical model produced by this study may guide future researchers and enhance the understanding and implementation of cloud computing technologies. The results of this study will add to the body of literature and may guide companies attempting to implement cloud computing to do so more successfully.
847

Secure Data Service Outsourcing with Untrusted Cloud

Xiong, Huijun 10 June 2013 (has links)
Outsourcing data services to the cloud is a nature fit for cloud usage. However, increasing security and privacy concerns from both enterprises and individuals on their outsourced data inhibit this trend. In this dissertation, we introduce service-centric solutions to address two types of security threats existing in the current cloud environments: semi-honest cloud providers and malicious cloud customers. Our solution aims not only to provide confidentiality and access controllability of outsourced data with strong cryptographic guarantee, but, more importantly, to fulfill specific security requirements from different cloud services with effective systematic ways. To provide strong cryptographic guarantee to outsourced data, we study the generic security problem caused by semi-honest cloud providers and introduce a novel proxy-based secure data outsourcing scheme. Specifically, our scheme improves the efficiency of traditional proxy re-encryption algorithm by integrating symmetric encryption and proxy re-encryption algorithms. With less computation cost on applying re-encryption operation directly on the encrypted data, our scheme allows flexible and efficient user revocation without revealing underlying data and heavy computation in the untrusted cloud. To address specific requirement from different cloud services, we investigate two specific cloud services: cloud-based content delivery service and cloud-based data processing service. For the former one, we focus on preserving cache property in the content delivery network and propose CloudSeal, a scheme for securely and flexibly sharing and distributing content via the public cloud. With the ability of caching the major part of a stored cipher content object in the delivery network for content distribution and keeping the minor part with the data owner for content authorization, CloudSeal achieves security and efficiency both theoretically and experimentally. For the later service, we design and realize CloudSafe, a framework that supports secure and efficient data processing with minimum key leakage in the vulnerable cloud virtualization environment. Through the adoption of one-time cryptographic key strategy and a centralized key management framework, CloudSafe efficiently avoids cross-VM side channel attack from malicious cloud customers in the cloud. Our experimental results confirm the practicality and scalability of CloudSafe. / Ph. D.
848

Riskmedvetenhet kring molntjänster hos studenter / Risk awareness regarding cloud services among students

Johansson, Eric, Süld, Niclas January 2021 (has links)
Användning av molntjänster har ökat senaste tiden, deras flexibilitet och tillgänglighet har gjort dem till ett lika bra, om inte bättre alternativ till lokal lagring och lokalt installerade programvaror. Denna typ av molnbaserade tjänster är beroende av Internet för att kunna fungera, detta gör datan känslig för eventuella attacker från illvilliga aktörer med en Internetuppkoppling. Alla är dock inte helt medvetna om vilka risker som kan finnas med dessa molntjänster. Covid-19-pandemin har accelererat övergången till molnet ytterligare och bidragit till att användare har blivit tvungna att arbeta och studera hemifrån. I denna uppsats har vi valt att fokusera på högskole- och universitetsstudenters riskmedvetenhet kring molntjänster. Deras kännedom om några av de vanligaste riskerna med molntjänster har undersökts genom en enkätundersökning. Resultatet visar att medvetenheten kring molntjänsters risker har ökat sedan det undersöktes senast. / This is a bachelor thesis written in Swedish about university student's risk awareness regarding cloud computing. The use of cloud computing has increased lately, their flexibility and availability has made them an equally good - if not better option to traditional locally run applications and local storage. Cloud computing is dependent on the Internet to function properly, the connection to the Internet makes them vulnerable to attacks from bad actors with an Internet connection. Despite the widespread use of these services everybody isn't aware of the risks they present. The Covid-19 pandemic has accelerated the increased use of these technologies further by making people work and study from home to a greater extent than before. In this bachelor thesis we have chosen to focus on university students' risk awareness regarding cloud computing. Their knowledge about some of cloud computing's most common risks have been studied using a survey. Results show that awareness has increased since it was last studied.
849

Cooperative Resource Sharing in Mobile Cloud Computing / モバイルクラウドコンピューティングにおける協調的資源共有

Liu, Wei 23 March 2015 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(情報学) / 甲第19132号 / 情博第578号 / 新制||情||101(附属図書館) / 32083 / 京都大学大学院情報学研究科通信情報システム専攻 / (主査)教授 高橋 達郎, 教授 原田 博司, 教授 梅野 健 / 学位規則第4条第1項該当 / Doctor of Informatics / Kyoto University / DFAM
850

Performance Modeling of Large-Scale Parallel-Distributed Processing for Cloud Environment / クラウド環境における大規模並列分散処理の性能モデル

Hirai, Tsuguhito 23 May 2018 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(情報学) / 甲第21280号 / 情博第674号 / 新制||情||116(附属図書館) / 京都大学大学院情報学研究科システム科学専攻 / (主査)教授 田中 利幸, 教授 山下 信雄, 准教授 増山 博之, 教授 笠原 正治 / 学位規則第4条第1項該当 / Doctor of Informatics / Kyoto University / DFAM

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