The isolation property of database theory guarantees to avoid problems of not synchronized parallel execution of several transactions. In this paper we propose an algorithm for an optimal transaction schedule for the different cores of a multi-core CPU with minimal execution time ensuring the isolation property. Optimizing the transaction schedule is a combinatorial problem, which is ideal to be solved by quantum annealers as special form of quantum computers. In our contribution we show how to transform an instance of the transaction schedule problem into a formula that is accepted by quantum annealers including a proof of validity and optimality of the obtained result. Furthermore, we analyze the number of required qubits and the preprocessing time, and introduce an approach for caching formulas as result of preprocessing for the purpose of reducing the preprocessing time. In an experimental evaluation, the runtime on a quantum annealer outperforms the runtime of traditional algorithms to solve combinatorial problems like simulated annealing already for small problem sizes.
Traditional clusters for cloud computing are quite hard to configure and setup, and the number of cluster nodes is limited by the available hardware in the cluster. We hence envision the concept of a Browser Cloud: One just has to visit with his/her web browser a certain webpage in order to connect his/her computer to the Browser Cloud. In this way the setup of the Browser Cloud is much easier than those of traditional clouds. Furthermore, the Browser Cloud has a much larger number of potential nodes, as any computer running a browser may connect to and be integrated in the Browser Cloud. New challenges arise when setting up a cloud by web browsers: Data is processed within the browser, which requires to use the technologies offered by the browser for this purpose. The typically used JavaScript runtime environment may be too slow, because JavaScript is an interpreted language. Hence we investigate the possibilities for computing the work-intensive part of the query processing inside a virtual machine of the web browser. The technology WebAssemby for virtual machines is recently supported by all major browsers and promises high speedups in comparison with JavaScript. Recent approaches to efficient Big Data processing generate code for the data processing steps of queries. To run the generated code in a WebAssembly virtual machine, an online compiler is needed to generate the WebAssembly bytecode from the generated code. Hence our main contribution is an online compiler to WebAssembly bytecode especially developed to run in the web browser and for Big Data processing based on code generation of the processing steps. In our experiments, the runtimes of Big Data processing using JavaScript is compared with running WebAssembly technologies in the major web browsers.
Low-cost clusters are not equipped with costly, sophisticated tools and cannot be controlled remotely. This work aims at addressing this issue and develops a lightweight network-controlled power strip, which enables administrators to monitor the cluster and perform operation via remote. The power strip is controlled via a web interface and a RESTful web service, which are implemented with the programming language Python and the web framework Flask. The solution is inexpensive and easy to implement and use. In this paper, we describe in detail the development and construction of the prototype of the solution and discuss its purchase cost and power consumption.
Cloud computing represents a significant paradigm shift in the delivery of information technology (IT) services. The rapid growth of the cloud and the increasing security concerns associated with the delivery of cloud services has led many researchers to study cloud risks and risk assessments. Some of these studies highlight the inability of current risk assessments to cope with the dynamic nature of the cloud, a gap we believe is as a result of the lack of consideration for the inherent risk of the supply chain. This paper, therefore, describes the cloud supply chain and investigates the effect of supply chain transparency in conducting a comprehensive risk assessment. We conducted an industry survey to gauge stakeholder awareness of supply chain risks, seeking to find out the risk assessment methods commonly used, factors that hindered a comprehensive evaluation and how the current state-of-the-art can be improved. The analysis of the survey dataset showed the lack of flexibility of the popular qualitative assessment methods in coping with the risks associated with the dynamic supply chain of cloud services, typically made up of an average of eight suppliers. To address these gaps, we propose a Cloud Supply Chain Cyber Risk Assessment (CSCCRA) model, a quantitative risk assessment model which is supported by decision support analysis and supply chain mapping in the identification, analysis and evaluation of cloud risks.
When an object-based storage service is demanded and the cost for purchase and operation of servers, workstations or personal computers is a challenge, single board computers may be an option to build an inexpensive system. This paper describes the lessons learned from deploying different private cloud storage services, which implement the functionality and API of the Amazon Simple Storage Service on a single board computer, the development of a lightweight tool to investigate the performance and an analysis of the archived measurement data. The objective of the performance evaluation is to get an impression, if it is possible and useful to deploy object-based storage services on single board computers.
Cloud computing is a business paradigm where two important roles must be defined: provider and consumer. Providers offer services (e.g. web application, web services, and databases) and consumers pay for using them. The goal of this research is to focus on security and compliance aspects of cloud service. An ontology is introduced, which is the conceptualization of cloud domain, for analyzing different compliance aspects of cloud agreements. The terms, properties and relations are shown in a diagram. The proposed ontology can help service consumers to extract relevant data from service level agreements, to interpret compliance regulations, and to compare different contractual terms. Finally, some recommendations are presented for cloud consumers to adopt services and evaluate security risks.
Dew computing is an emerging new research area and has great potentials in applications. In this paper, we propose a revised definition of dew computing. The new definition is: Dew computing is an on-premises computer software-hardware organization paradigm in the cloud computing environment where the on-premises computer provides functionality that is independent of cloud services and is also collaborative with cloud services. The goal of dew computing is to fully realize the potentials of on-premises computers and cloud services. This definition emphasizes two key features of dew computing: independence and collaboration. Furthermore, we propose a group of dew computing categories. These categories may inspire new applications.
While the popularity of cloud computing is exploding, a new network computing paradigm is just beginning. In this paper, we examine this exciting area of research known as dew computing and propose a new design of cloud-dew architecture. Instead of hosting only one dew server on a user's PC - as adopted in the current dewsite application - our design promotes the hosting of multiple dew servers instead, one for each installed domain. Our design intends to improve upon existing cloud-dew architecture by providing significantly increased freedom in dewsite development, while also automating the chore of managing dewsite content based on the user's interests and browsing habits. Other noteworthy benefits, all at no added cost to dewsite users, are briefly explored as well.
Cloud Federation is an emerging technology where Cloud Service Providers (CSPs) offering specialized services to customers collaborate in order to reap the real benefits of Cloud Computing. When a CSP in the Cloud Federation runs out of resources, it can get the required resources from other partners in the federation. Normally, there will be QoS agreements between the partners in the federation for the resource sharing. In this paper, we propose a trust based mechanism for the management of dynamic QoS violations, when one CSP requests resources from another CSP in the federation. In this work, we have implemented the partner selection process, when one CSP does not have enough resources, using the Analytic Hierarchy Process (AHP) and the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) methods, and also considering the trust values of various CSPs in the federation. We have also implemented the Single Sign-On (SSO) authentication in the cloud federation using the Fully Hashed Menezes-Qu-Vanstone (FHMQV) protocol and AES-256 algorithm. The proposed trust-based approach is used to dynamically manage the QoS violations among the partners in the federation. We have implemented the proposed approach using the CloudSim toolkit, and the analysis of the results are also given.
Cloud computing provides on-demand access to a shared pool of configurable and dynamically reallocated computing resources typically located in third-party data centers. Ubiquitous computing aims at providing computing resources anytime and everywhere by using any device, in any location, and in any format. This special issue, Advances in Cloud and Ubiquitous Computing (ACUC), aims at addressing the challenges and reporting the latest research findings in the fields of Cloud computing and Ubiquitous Computing respectively, and how new technologies of Cloud Computing and Ubiquitous Computing complete each other.
Multi-core clusters have emerged as an important contribution in computing technology for provisioning additional processing power in high performance computing and communications. Multi-core architectures are proposed for their capability to provide higher performance without increasing heat and power usage, which is the main concern in a single-core processor. This paper introduces analytical models of a new architecture for large-scale multi-core clusters to improve the communication performance within the interconnection network. The new architecture will be based on a multi - cluster architecture containing clusters of multi-core processors.
“The cloud” is widely advertised as a silver bullet for many IT-related challenges of small and medium-sized enterprises (SMEs). While it can potentially have a number of attractive benefits, many SMEs refrain from using cloud sourcing and cloud services because of high upfront costs for building the appropriate knowledge in the enterprise, for searching and screening of possible cloud service providers, and for mastering the intricate legal issues related to outsourcing sensitive data. This paper presents the concept of hybrid cloud intermediaries, an approach that can address many of the prevailing issues. With the aid of empirical findings from a cross-nation study of cloud adoption in SMEs for context, we describe the concept in detail and show conceivable variants, including a comprehensive cross-perspective consolidated model of cloud intermediary value-creation. Subsequently, we analyze the benefits of such a hybrid cloud intermediary for addressing cloud adoption issues in SMEs, and suggest suitable governance structures based on the cooperative paradigm. The resulting entity — a cooperative hybrid cloud intermediary or, more concisely, co-op cloud — is discussed in detail showing both feasible scenarios and limitations for SMEs that would like to engage in a cloud-sourcing. TYPE OF PAPER AND KEYWORDS Visionary paper: Cloud Intermediary, Cloud Service, IT-Outsourcing, small enterprises, medium-sized enterprises
The paper considers the conceptual approach for organization of the vertical hierarchical links between the scalable distributed computing paradigms: Cloud Computing, Fog Computing and Dew Computing. In this paper, the Dew Computing is described and recognized as a new structural layer in the existing distributed computing hierarchy. In the existing computing hierarchy, the Dew computing is positioned as the ground level for the Cloud and Fog computing paradigms. Vertical, complementary, hierarchical division from Cloud to Dew Computing satisfies the needs of high- and low-end computing demands in everyday life and work. These new computing paradigms lower the cost and improve the performance, particularly for concepts and applications such as the Internet of Things (IoT) and the Internet of Everything (IoE). In addition, the Dew computing paradigm will require new programming models that will efficiently reduce the complexity and improve the productivity and usability of scalable distributed computing, following the principles of High-Productivity computing.
This special issue of Open Journal of Cloud Computing (OJCC) (www.ronpub.com/journals/ojcc) reports work in the field of emerging software as a service and analytics, and presents innovative approaches to delivering software services in research and enterprise communities. It contains extended versions of papers selected from the international workshop on Emerging Software as a Service and Analytices (ESaaSA) in association with the international conference on cloud computing and serviced science taken place in Barcelona, Spain during April 2014. OJCC is published by RonPub (www.ronpub.com), which is an academic publisher of online, open access, peer-reviewed journals.
This paper introduces the Risk Visualization as a Service (RVaaS) and presents the motivation, rationale, methodology, Cloud APIs used, operations and examples of using RVaaS. Risks can be calculated within seconds and presented in the form of Visualization to ensure that unexploited areas are ex-posed. RVaaS operates in two phases. The first phase includes the risk modeling in Black Scholes Model (BSM), creating 3D Visualization and Analysis. The second phase consists of calculating key derivatives such as Delta and Theta for financial modeling. Risks presented in visualization allow the potential investors and stakeholders to keep track of the status of risk with regard to time, prices and volatility. Our approach can improve accuracy and performance. Results in experiments show that RVaaS can perform up to 500,000 simulations and complete all simulations within 24 seconds for time steps of up to 50. We also introduce financial stock market analysis (FSMA) that can fully blend with RVaaS and demonstrate two examples that can help investors make better decision based on the pricing and market volatility information. RVaaS provides a structured way to deploy low cost, high quality risk assessment and support real-time calculations.
Deduplication is a storage saving technique which has been adopted by many cloud storage providers such as Dropbox. The simple principle of deduplication is that duplicate data uploaded by different users are stored only once. Unfortunately, deduplication is not compatible with encryption. As a scheme that allows deduplication of encrypted data segments, we propose ClouDedup, a secure and efficient storage service which guarantees blocklevel deduplication and data confidentiality at the same time. ClouDedup strengthens convergent encryption by employing a component that implements an additional encryption operation and an access control mechanism. We also propose to introduce an additional component which is in charge of providing a key management system for data blocks together with the actual deduplication operation. We show that the overhead introduced by these new components is minimal and does not impact the overall storage and computational costs.
Clouds are dynamic networks of common, off-the-shell computers to build computation farms. The rapid growth of databases in the context of the semantic web requires efficient ways to store and process this data. Using cloud technology for storing and processing Semantic Web data is an obvious way to overcome difficulties in storing and processing the enormously large present and future datasets of the Semantic Web. This paper presents a new approach for storing Semantic Web data, such that operations for the evaluation of Semantic Web queries are more likely to be processed only on local data, instead of using costly distributed operations. An experimental evaluation demonstrates the performance improvements in comparison to a naive distribution of Semantic Web data.
Cloud has emerged as a new computing paradigm that promises to move into computing-as-utility era. Desktop Cloud is a new type of Cloud computing introduced to further achieve this ambition with an aim to reduce costs. It merges two computing models: Cloud computing and volunteer computing. The aim of Desktop Cloud is to provide Cloud services out of infrastructure that is not made for this purpose, like PCs and laptops. Such computing resources lead to a high level of volatility as a result of the fact that they can leave without prior knowledge. This paper studies the impact of node failures using evaluation metrics based on real data collected from public archive to simulate failure events in the infrastructure of a Desktop Cloud. The contribution of this paper is: (i) analysing the failure events, (ii) proposing metrics to evaluate Desktop Clouds, and (iii) evaluating several VM allocation mechanisms in the presence of node failures.
This paper presents the customer satisfaction analysis for measuring popularity in the Mobile Cloud, which is an emerging area in the Cloud and Big Data Computing. Organizational Sustainability Modeling (OSM) is the proposed method used in this research. The twelve-month of German and Spanish consumer data are used for the analysis to investigate the return and risk status associated with the ratings of customer satisfaction in the iPhone 4S Mobile Cloud services. Results show that there is a decline in the satisfaction ratings in Germany and Spain due to economic downturn and competitions in the market, which support our hypothesis. Key outputs have been explained and they confirm that all analysis and interpretations fulfill the criteria for OSM. The use of statistical and visualization method proposed by OSM can expose unexploited data and allows the stakeholders to understand the status of return and risk of their Cloud strategies easier than the use of other data analysis.
