32 research outputs found

    ClouDiA: a deployment advisor for public clouds

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    An increasing number of distributed data-driven applications are moving into shared public clouds. By sharing resources and oper-ating at scale, public clouds promise higher utilization and lower costs than private clusters. To achieve high utilization, however, cloud providers inevitably allocate virtual machine instances non-contiguously, i.e., instances of a given application may end up in physically distant machines in the cloud. This allocation strategy can lead to large differences in average latency between instances. For a large class of applications, this difference can result in signif-icant performance degradation, unless care is taken in how applica-tion components are mapped to instances. In this paper, we propose ClouDiA, a general deployment ad-visor that selects application node deployments minimizing either (i) the largest latency between application nodes, or (ii) the longest critical path among all application nodes. ClouDiA employs mixed-integer programming and constraint programming techniques to ef-ficiently search the space of possible mappings of application nodes to instances. Through experiments with synthetic and real applica-tions in Amazon EC2, we show that our techniques yield a 15 % to 55 % reduction in time-to-solution or service response time, without any need for modifying application code. 1

    A DISTRIBUTED E-LEARNING SERVICE FOR REMOTE AREAS

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    The cloud-compatible architecture of a distributed distance e-learning system which has been deployed and is being utilized in five remote areas in Eastern Europe (Finland, Poland, Bulgaria, Greece and Cyprus) is presented and discussed as a case study of e-learning. A series of e-courses is being conducted with a variety of learning tools and techniques: a Virtual World, Web 2.0 tools, a web conference platform and a learning management system. Emphasis is placed on the feasibility of the delivery of the integrated Distance Learning (DL) service through distributed web services; an architecture is proposed that extends the existing one by implementing the DL service in the form of a SOA in a hybrid cloud

    Proposed object-based e-learning framework embracing cloud computing

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    E-learning is continually evolved in the adaptation of emerging technologies and pedagogies, so does the development of learning objects. Object-based learning approach has been widely adopted in e-learning.The principle concern in the conventional e-learning models is the inflexibility of the e-learning content to assist the use and management of the learning sources which are highly distributed.Rigidity of e-learning content limits its reusability and shareability.Possessing the ability to deliver strong computing power and secure data storage as services, Cloud computing is a promising computing model to promote innovative changes and add notable values to e-learning landscape.The flexibility and on-demand access to a centralized shared pool of computing resources provided by Cloud computing enables high re-usability and share-ability, hence overcomes the principle concern in e-learning due to the rigidity of e-learning content.This paper describes the design of an object-based e-learning framework embracing Cloud computing.The proposed object-based e learning framework can be used to form a new education domain that shares the Cloud characteristics of elasticity, flexibility, efficiency and reliability.Principal to the framework design is the development of Cloud-based e-learning objects where learners have the flexibility to access, personalize and deploy them in e-learning environment.Cloud-based e-learning objects are highly adaptable, reusable and easy changeable, hence allowing them to be used dynamically with greater customizability and flexibility in e-learning.Adapting Cloud computing into object-based e-learning is believed to be able to create a breakthrough in future dynamic -e-learning development

    Security Audit Compliance for Cloud Computing

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    Cloud computing has grown largely over the past three years and is widely popular amongst today's IT landscape. In a comparative study between 250 IT decision makers of UK companies they said, that they already use cloud services for 61% of their systems. Cloud vendors promise "infinite scalability and resources" combined with on-demand access from everywhere. This lets cloud users quickly forget, that there is still a real IT infrastructure behind a cloud. Due to virtualization and multi-tenancy the complexity of these infrastructures is even increased compared to traditional data centers, while it is hidden from the user and outside of his control. This makes management of service provisioning, monitoring, backup, disaster recovery and especially security more complicated. Due to this, and a number of severe security incidents at commercial providers in recent years there is a growing lack of trust in cloud infrastructures. This thesis presents research on cloud security challenges and how they can be addressed by cloud security audits. Security requirements of an Infrastructure as a Service (IaaS) cloud are identified and it is shown how they differ from traditional data centres. To address cloud specific security challenges, a new cloud audit criteria catalogue is developed. Subsequently, a novel cloud security audit system gets developed, which provides a flexible audit architecture for frequently changing cloud infrastructures. It is based on lightweight software agents, which monitor key events in a cloud and trigger specific targeted security audits on demand - on a customer and a cloud provider perspective. To enable these concurrent cloud audits, a Cloud Audit Policy Language is developed and integrated into the audit architecture. Furthermore, to address advanced cloud specific security challenges, an anomaly detection system based on machine learning technology is developed. By creating cloud usage profiles, a continuous evaluation of events - customer specific as well as customer overspanning - helps to detect anomalies within an IaaS cloud. The feasibility of the research is presented as a prototype and its functionality is presented in three demonstrations. Results prove, that the developed cloud audit architecture is able to mitigate cloud specific security challenges

    Cloud e-learning for mechatronics: CLEM

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    his paper describes results of the CLEM project, Cloud E-learning for Mechatronics. CLEM is an example of a domain-specific cloud that is especially tuned to the needs of VET (Vocational, Education and Training) teachers. An interesting development has been the creation of remote laboratories in the cloud. Learners can access such laboratories to support their practical learning of mechatronics without the need to set up laboratories at their own institutions. The cloud infrastructure enables multiple laboratories to come together virtually to create an ecosystem for educators and learners. From such a system, educators can pick and mix materials to create suitable courses for their students and the learners can experience different types of devices and laboratories through the cloud. The paper provides an overview of this new cloud-based e-learning approach and presents the results. The paper explains how the use of cloud computing has enabled the development of a new method, showing how a holistic e-learning experience can be obtained through use of static, dynamic and interactive material together with facilities for collaboration and innovation

    The adoption of cloud computing by SMEs: identifying and coping with external factors.

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    Comunicação apresentada na CAPSI 2011 - 11ª Conferência da Associação Portuguesa de Sistemas de Informação – A Gestão de Informação na era da Cloud Computing, Lisboa, ISEG/IUL-ISCTE/, 19 a 21 de Outubro de 2011.The recent development of Cloud Computing (CC) provides a convincing opportunity for organizations to outsource their Information and Communications Technology (ICT). Although its popularity is increasing rapidly, there are concerns that must be taken into account. This paper ascertains the most relevant issues associated with the political, economic, social and technological factors concerning CC adoption. The research described is based on a scoping review to identify relevant studies published in the literature recently. The aim is to provide an overview of the most recent findings in the Cloud Computing environment, which can inform strategic decision-making by Small to Medium-sized Enterprises (SMEs) in this area

    Design and Assessment of an Experimental SDN-Enabled Private Cloud using Openstack

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    Nowadays, educational and research institutions, especially universities, have considered their focus on cloud computing rather than using conventional prospects to take the most benefits of the services offered to support current trends in teaching and learning strategies. To build these networks in a cost effective way, open source cloud computing platforms are used. One of the powerful tools is Openstack, which allows users to create virtual networks and manage virtual machines within distributed learning environments. In this article, we describe our project on designing and evaluating a private cloud within a university environment using Openstack. To this end, we conduct a survey to measure the students’ attitude towards the use of private clouds in which students and experts serve as samples. We design a virtual lab consisting of a number of virtual machines operated by a selected sample. We evaluate the proposed solution by adopting Technology Acceptance Model (TAM) methodology. The results obtained from this study show that the students’ acceptance in using the private cloud in performing their tasks is encouraging albeit their anxiety on security issues and their lack of experience
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