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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.
211

Study on Architecture-Oriented Enterprise Private Cloud Model

Hsu, Chine-chuan 12 June 2012 (has links)
Cloud computing has updated the appearance of the Information Technology (IT) infrastructure, and in addition to lower operation costs provides real-time services and reduces the information service barrier. In order to adapt to the rapidly changing market demand, enterprises are beginning to consider the feasibility of the deployment of cloud computing. The business environment changes so fast that an integrated dynamic framework and intelligent service system to achieve enterprises¡¦ visions, objectives and strategies, and to quick response is needed. Regarding to the three main service types of cloud computing: Software as a Service (SaaS), Platform as a Service (PaaS), Infrastructure as a Service (IaaS), this study proposes an integration model for enterprise administration. Cloud computing packs the functionality of dynamic resource adjustment. From the deployment of organizations to the customer interactions, cloud computing is divided into a public cloud, private cloud and mixed cloud based on its deployment model. As for the private cloud, its information security and efficiency allow enterprises execute their operations smoothly according to the business rules. Thus more and more enterprises are inclined to deploy private clouds. This study uses structure-behavior coalescence architecture description language (SBC-ADL) to accomplish the systems architecture, and provides thorough suggestions of dynamic resources allocation as a reference model for any enterprise which plans to deploy the cloud computing service. For those enterprises that have already implemented cloud computing services, the systems architecture can be referred to better their business management. Describing the relationship between the various systems architecture is helpful in quickly understanding the system operation. Consider reducing misunderstanding and increasing work efficiency and information correctness, SBC-ADL works very well as an effective tool for training and communication within the IT department.
212

The Design of Cloud-Economical Computing Services for Program Trading

Hsu, Chi-Shin 26 August 2012 (has links)
Program Trading has gotten more popular recent years. According to thestatistics, there was about 53.6% of daily volume in the United States, and increased to 73% in 2009. With the universal of program trading, more people have begun to research program trading. The purpose of this paper is constructing a developed platform of program trading for researching or developing. In addition to developed platform, we provide the run-time environment, and three main functions: 1. The job scheduler 2. The high scalability 3. The developed platform In this paper, we use SLURM to implement an economical computing service for program trading. SLURM is a resource management software for some large clusters. However it lacked for an easy interface to the ended users. We modify Xinetd as the external interface for SLURM, and implement the program trading development platform for researching or developing. According to the result, using our scheduler and the external interface that modify from Xinetd can be effective in controlling the server resource and increase the availability.
213

Applying MapReduce Island-based Genetic Algorithm-Particle Swarm Optimization to the inference of large Gene Regulatory Network in Cloud Computing environment

Huang, Wei-Jhe 13 September 2012 (has links)
The construction of Gene Regulatory Networks (GRNs) is one of the most important issues in systems biology. To infer a large-scale GRN with a nonlinear mathematical model, researchers need to encounter the time-consuming problem due to the large number of network parameters involved. In recent years, the cloud computing technique has been widely used to solve large-scale problems. Among others, Hadoop is currently the most well-known and reliable cloud computing framework, which allows users to analyze large amount of data in a distributed environment (i.e., MapReduce). It also supports data backup and data recovery mechanisms. This study proposes an Island-based GAPSO algorithm under the Hadoop cloud computing environment to infer large-scale GRNs. GAPSO exploited the position and velocity functions of PSO, and integrated the operations of Genetic Algorithm. This approach is often used to derive the optimal solution in nonlinear mathematical models. Several sets of experiments have been conducted, in which the number of network nodes varied from 50 to 125. The experiments were executed in the Hadoop distributed environment with 10, 20, and 26 computers, respectively. In the experiments of inferring the network with 125 gene nodes on the largest Hadoop cluster (i.e. 26 computers), the proposed framework performed up to 9.7 times faster than the stand-alone computer. It means that our work can successfully reduce 90% of the computation time in a single experimental run.
214

Cloud Computing Evaluation : How it Differs to Traditional IT Outsourcing

Brunzel, Tino, Di Giacomo, Débora January 2010 (has links)
<p><strong>Introduction</strong></p><p>Cloud Computing, that is providing computer resources as a service, is a technology revolution offering flexible IT usage in a cost efficient and pay-per-use way. As for the evaluation of companies to whether which technology solution to use, it would be necessary to decide whether or not the evaluation of cloud computing would actually differ to the traditional way of IT outsourcing.</p><p><strong></strong><strong>Problem Discussion</strong></p><p>Outsourcing IT capabilities are a crucial and inevitable step for enterprises that want to survive in the currently high competitive climate. Until now most of the researches, that has been done so far, only consider the XaaS model only from a traditional IT outsourcing point of view rather than in the cloud computing context. This research will now include the evaluation of cloud solutions giving companies another possibility to outsource their IT resources.</p><p><strong></strong><strong>Purpose</strong></p><p><strong></strong>The purpose is now to see how the evaluation of cloud computing possibilities as an outsourcing option actually differs to traditional IT outsourcing. One aspect that needs to be covered with this purpose, is whether it is possible to evaluate the source through a cloud computing solution with the same concepts and theories used to evaluate traditional IT outsourcing. It will also be the purpose to see, which aspects need to be added or removed when considering a cloud computing opportunity compared to the traditional IT outsourcing.</p><p><strong></strong><strong>Method </strong></p><p>With help of the theoretical framework, interviews have been launched with three companies to see what their general opinion and knowledge is on the evaluation of cloud computing and its maturity. Questions have been asked openly so that answers could not be directed or manipulated by the authors of the research.</p><p><strong></strong><strong>Conclusion</strong></p><p>After challenging the theoretical framework against the data collected, the traditional IT outsourcing theories appeared to be valid also for the evaluation of cloud computing solutions. Some important concepts are added to the evaluation of cloud computing solutions in consequence of particularities present in the model.</p>
215

Planning and Optimization During the Life-Cycle of Service Level Agreements for Cloud Computing

Lu, Kuan 16 February 2015 (has links)
Ein Service Level Agreement (SLA) ist ein elektronischer Vertrag zwischen dem Kunden und dem Anbieter eines Services. Die beteiligten Partner kl aren ihre Erwartungen und Verp ichtungen in Bezug auf den Dienst und dessen Qualit at. SLAs werden bereits f ur die Beschreibung von Cloud-Computing-Diensten eingesetzt. Der Diensteanbieter stellt sicher, dass die Dienstqualit at erf ullt wird und mit den Anforderungen des Kunden bis zum Ende der vereinbarten Laufzeit ubereinstimmt. Die Durchf uhrung der SLAs erfordert einen erheblichen Aufwand, um Autonomie, Wirtschaftlichkeit und E zienz zu erreichen. Der gegenw artige Stand der Technik im SLA-Management begegnet Herausforderungen wie SLA-Darstellung f ur Cloud- Dienste, gesch aftsbezogene SLA-Optimierungen, Dienste-Outsourcing und Ressourcenmanagement. Diese Gebiete scha en zentrale und aktuelle Forschungsthemen. Das Management von SLAs in unterschiedlichen Phasen w ahrend ihrer Laufzeit erfordert eine daf ur entwickelte Methodik. Dadurch wird die Realisierung von Cloud SLAManagement vereinfacht. Ich pr asentiere ein breit gef achertes Modell im SLA-Laufzeitmanagement, das die genannten Herausforderungen adressiert. Diese Herangehensweise erm oglicht eine automatische Dienstemodellierung, sowie Aushandlung, Bereitstellung und Monitoring von SLAs. W ahrend der Erstellungsphase skizziere ich, wie die Modellierungsstrukturen verbessert und vereinfacht werden k onnen. Ein weiteres Ziel von meinem Ansatz ist die Minimierung von Implementierungs- und Outsourcingkosten zugunsten von Wettbewerbsf ahigkeit. In der SLA-Monitoringphase entwickle ich Strategien f ur die Auswahl und Zuweisung von virtuellen Cloud Ressourcen in Migrationsphasen. Anschlie end pr ufe ich mittels Monitoring eine gr o ere Zusammenstellung von SLAs, ob die vereinbarten Fehlertoleranzen eingehalten werden. Die vorliegende Arbeit leistet einen Beitrag zu einem Entwurf der GWDG und deren wissenschaftlichen Communities. Die Forschung, die zu dieser Doktorarbeit gef uhrt hat, wurde als Teil von dem SLA@SOI EU/FP7 integriertem Projekt durchgef uhrt (contract No. 216556).
216

Optimal divisible resource allocation for self-organizing cloud

Di, Sheng, 狄盛 January 2011 (has links)
published_or_final_version / Computer Science / Doctoral / Doctor of Philosophy
217

Network performance isolation for virtual machines

Cheng, Luwei., 程芦伟. January 2011 (has links)
Cloud computing is a new computing paradigm that aims to transform computing services into a utility, just as providing electricity in a “pay-as-you-go” manner. Data centers are increasingly adopting virtualization technology for the purpose of server consolidation, flexible resource management and better fault tolerance. Virtualization-based cloud services host networked applications in virtual machines (VMs), with each VM provided the desired amount of resources using resource isolation mechanisms. Effective network performance isolation is fundamental to data centers, which offers significant benefit of performance predictability for applications. This research is application-driven. We study how network performance isolation can be achieved for latency-sensitive cloud applications. For media streaming applications, network performance isolation means both predicable network bandwidth and low-jittered network latency. The current resource sharing methods for VMs mainly focus on resource proportional share, whereas ignore the fact that I/O latency in VM-hosted platforms is mostly related to resource provisioning rate. The resource isolation with only quantitative promise does not sufficiently guarantee performance isolation. Even the VM is allocated with adequate resources such as CPU time and network bandwidth, problems such as network jitter (variation in packet delays) can still happen if the resources are provisioned at inappropriate moments. So in order to achieve performance isolation, the problem is not only how many/much resources each VM gets, but more importantly whether the resources are provisioned in a timely manner. How to guarantee both requirements to be achieved in resource allocation is challenging. This thesis systematically analyzes the causes of unpredictable network latency in VM-hosted platforms, with both technical discussion and experimental illustration. We identify that the varied network latency is jointly caused by VMM CPU scheduler and network traffic shaper, and then address the problem in these two parts. In our solutions, we consider the design goals of resource provisioning rate and resource proportionality as two orthogonal dimensions. In the hypervisor, a proportional share CPU scheduler with soft real-time support is proposed to guarantee predictable scheduling delay; in network traffic shaper, we introduce the concept of smooth window to smooth packet delay and apply closed-loop feedback control to maintain network bandwidth consumption. The solutions are implemented in Xen 4.1.0 and Linux 2.6.32.13, which are both the latest versions when this research was conducted. Extensive experiments have been carried out using both real-life applications and low-level benchmarks. Testing results show that the proposed solutions can effectively guarantee network performance isolation, by achieving both predefined network bandwidth and low-jittered network latency. / published_or_final_version / Computer Science / Master / Master of Philosophy
218

Cost-aware online VM purchasing for cloud-based application service providers with arbitrary demands

Shi, Shengkai, 石晟恺 January 2014 (has links)
Recent years witness the proliferation of Infrastructure-as-a-Service (IaaS) cloud services, which provide on-demand resources (CPU, RAM, disk, etc.) in the form of virtual machines (VMs) for hosting services of third parties. As such, the way of enabling scalable and dynamic Internet applications has been remarkably revolutionized. More and more Application Service Providers (ASPs) are launching their applications in clouds, eliminating the need to construct and operate their owned IT hardware and software. Given the state-of-the-art IaaS offerings, it is still a problem of fundamental importance how the ASPs should rent VMs from the clouds to serve their application needs, in order to minimize the cost while meeting their job demands over a long run. Cloud providers offer different pricing options to meet computing requirements of a variety of applications. The commonly adopted cloud pricing schemes are (1) reserved instance pricing, (2) on-demand instance pricing, and (3) spot instance pricing. However, the challenge facing an ASP is how these pricing schemes can be blended to accommodate arbitrary demands at the optimal cost. In this thesis, we seek to integrate all available pricing options and design effective online algorithms for the long-term operation of ASPs. We formulate the long-term-averaged VM cost minimization problem of an ASP with time-varying and delay-tolerant workloads in a stochastic optimization model. An efficient online VM purchasing algorithm is designed to guide the VM purchasing decisions of the ASP based on the Lyapunov optimization technique. In stark contrast with the existing studies, our online VM purchasing algorithm does not require any a priori knowledge of the workload or any future information. Moreover, it addresses the possible job interruption due to uncertain availability of spot instances. Rigorous analysis shows that our algorithm can achieve a time-averaged VM purchasing cost with a constant gap from its offline minimum. Trace-driven simulations further verify the efficacy of our algorithm. / published_or_final_version / Computer Science / Master / Master of Philosophy
219

A framework for cloud computing readiness assessment.

Ramothibe, Lydia. January 2012 (has links)
M. Tech. Information Networks (Structured) / Universities are currently spending huge sums of money on ICT both acquiring and maintaining. However, much as huge sums are spent, several complaints and strikes from the stakeholders are still prevalent. The stakeholders who happen to be mostly students are ever complaining of poor and slow services. The university has experienced intermittent network connections, leaving the staff both administrators and lecturers in a major dilemma as they can't effectively and efficiently apply to their work. These upheavals have at many times ended up destructing academic programs and to some extent vandalizing of university property has been a common face. Hence, the need for the assessment of cloud computing that could provide a stable and dependable network connection. The major goal of this study was to develop a conceptual framework that will systematically organize the assessment of factors needed to determine cloud computing readiness at South African Universities.
220

Ανάπτυξη εφαρμογής cloud για διαδικτυακές υπηρεσίες

Παναγιώτου, Ιωάννης 04 November 2014 (has links)
Το αντικείμενο της παρούσας Διπλωματικής Εργασίας είναι η ανάπτυξη και υλοποίηση μιας εφαρμογής cloud για διαδικτυακές υπηρεσίες. Συγκεκριμένα, η εφαρμογή ονομάζεται My Calendar και αφορά ένα προσωπικό ημερολόγιο. Η εφαρμογή βρίσκεται στην υποδομή «νέφους» της Google και οι τελικοί χρήστες μπορούν να έχουν πρόσβαση στην υπηρεσία μέσω ενός web browser. Αρχικά, γίνεται η εισαγωγή στις έννοιες του cloud computing καθώς και σε αυτές της πλατφόρμας της Google. Στη συνέχεια παρουσιάζεται ο τρόπος υλοποίησης της εφαρμογής και αναλύονται οι λειτουργίες της. Ο εκάστοτε χρήστης, αφού πρώτα δημιουργήσει τον προσωπικό του λογαριασμό, μπορεί να έχει πρόσβαση στην παρεχόμενη υπηρεσία. Η προσπάθεια επικεντρώθηκε κυρίως στην παρουσίαση μιας απλής και εύχρηστης εφαρμογής και δόθηκε ιδιαίτερη έμφαση στο λειτουργικό κομμάτι, ώστε και ο πλέον άπειρος χρήστης να κατανοεί τη διαδικασία και να μπορεί να χρησιμοποιεί την εφαρμογή εύκολα και γρήγορα για τις καθημερινές του εργασίες οργανώνοντας το πρόγραμμά του. / This diploma thesis deals with the development of a cloud application for web services. The application is called “My Calendar” and it is hosted on Google’s infrastructure. Everyone can access it from a simple web browser. First of all, we make an introduction in order to understand the meaning of cloud computing and be able to handle with the Google Cloud Platform. We describe the deployment of the application and we present its operations. Users must register in order to login and, after that, they could enter the interface which enables them to organize their schedule. We tried to focus on creating a user-friendly application and we emphasized on the functionality, so even the most inexperienced user could easily cope with it. As a result, we developed “My Calendar” with a view to everyone who wants to manage his/her scheduled tasks.

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