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Showing papers on "Software as a service published in 2012"


Proceedings ArticleDOI
01 Dec 2012
TL;DR: How Internet of Things and Cloud computing can work together can address the Big Data issues is described and a prototype model for providing sensing as a service on cloud is proposed.
Abstract: Internet of Things (IoT) is a concept that envisions all objects around us as part of internet. IoT coverage is very wide and include variety of objects like smart phones, tablets, digital cameras, sensors, etc. Once all these devices are connected with each other, they enable more and more smart processes and services that support our basic needs, economies, environment and health. Such enormous number of devices connected to internet provides many kinds of services and produce huge amount of data and information. Cloud computing is a model for on-demand access to a shared pool of configurable resources (e.g. compute, networks, servers, storage, applications, services, and software) that can be easily provisioned as Infrastructure (IaaS), software and applications (SaaS). Cloud based platforms help to connect to the things (IaaS) around us so that we can access anything at any time and any place in a user friendly manner using customized portals and in built applications (SaaS). Hence, cloud acts as a front end to access Internet of Things. Applications that interact with devices like sensors have special requirements of massive storage to storage big data, huge computation power to enable the real time processing of the data, and high speed network to stream audio or video. In this paper, we describe how Internet of Things and Cloud computing can work together can address the Big Data issues. We also illustrate about Sensing as a service on cloud using few applications like Augmented Reality, Agriculture and Environment monitoring. Finally, we also propose a prototype model for providing sensing as a service on cloud.

281 citations


Journal ArticleDOI
TL;DR: An extensive evaluation study is conducted to analyse which solution suits best in which scenario to maximize SaaS [email protected]?s profit and shows that the proposed algorithms provide substantial improvement over reference ones across all ranges of variation in QoS parameters.

229 citations


Journal ArticleDOI
TL;DR: Globus Online manages fire-and-forget file transfers for big-data, high-performance scientific collaborations.
Abstract: Globus Online manages fire-and-forget file transfers for big-data, high-performance scientific collaborations.

218 citations


Journal ArticleDOI
TL;DR: Conreteness is added to the federated Cloud model by considering how it works in delivering the Weather Research and Forecasting service as SaaS using PaaS and IaaS support, and WRF is used to illustrate the concepts of delegation and federation.

210 citations


Journal ArticleDOI
TL;DR: To protect valuable information, organisations must stop making a distinction between devices in the corporate network and devices outside of it, argues Bill Morrow of Quarri Technologies.

163 citations


Journal ArticleDOI
TL;DR: This article reviews extant cloud-based services in bioinformatics, classify them into Data as a Service (DaaS), Software as a service (SaaS%), Platform as aservice (PaaS) and Infrastructure as aService (IaaS); and presents perspectives on the adoption of cloud computing in bio informatics.
Abstract: As advances in life sciences and information technology bring profound influences on bioinformatics due to its interdisciplinary nature, bioinformatics is experiencing a new leap-forward from in-house computing infrastructure into utility-supplied cloud computing delivered over the Internet, in order to handle the vast quantities of biological data generated by high-throughput experimental technologies. Albeit relatively new, cloud computing promises to address big data storage and analysis issues in the bioinformatics field. Here we review extant cloud-based services in bioinformatics, classify them into Data as a Service (DaaS), Software as a Service (SaaS), Platform as a Service (PaaS), and Infrastructure as a Service (IaaS), and present our perspectives on the adoption of cloud computing in bioinformatics.

155 citations


Journal ArticleDOI
TL;DR: To make the development of open scientific software more rewarding and the experience of using software more positive, the following ten rules are intended to serve as a guide for any computational scientist.
Abstract: Open-source software development has had significant impact, not only on society, but also on scientific research. Papers describing software published as open source are amongst the most widely cited publications (e.g., BLAST [1], [2] and Clustal-W [3]), suggesting many scientific studies may not have been possible without some kind of open software to collect observations, analyze data, or present results. It is surprising, therefore, that so few papers are accompanied by open software, given the benefits that this may bring. Publication of the source code you write not only can increase your impact [4], but also is essential if others are to be able to reproduce your results. Reproducibility is a tenet of computational science [5], and critical for pipelines employed in data-driven biological research. Publishing the source for the software you created as well as input data and results allows others to better understand your methodology, and why it produces, or fails to produce, expected results. Public release might not always be possible, perhaps due to intellectual property policies at your or your collaborators' institutes; and it is important to make sure you know the regulations that apply to you. Open licensing models can be incredibly flexible and do not always prevent commercial software release [5]. Simply releasing the source under an open license, however, is not sufficient if you wish your code to remain useful beyond its publication [6]. The sustainability of software after publication is probably the biggest problem faced by researchers who develop it, and it is here that participating in open development from the outset can make the biggest impact. Grant-based funding is often exhausted shortly after new software is released, and without support, in-house maintenance of the software and the systems it depends on becomes a struggle. As a consequence, the software will cease to work or become unavailable for download fairly quickly [7], which may contravene archival policies stipulated by your journal or funding body. A collaborative and open project allows you to spread the resource and maintenance load to minimize these risks, and significantly contributes to the sustainability of your software. If you have the choice, embracing an open approach to development has tremendous benefits. It allows you to build on the work of other scientists, and enables others to build on your own efforts. To make the development of open scientific software more rewarding and the experience of using software more positive, the following ten rules are intended to serve as a guide for any computational scientist.

133 citations


Journal ArticleDOI
TL;DR: In this paper, the authors compared global IT outsourcing with cloud computing along with the evolution of traditional IT services and found that cloud computing is a model for provisioning and consuming IT capabilities on a need and pay by use basis.
Abstract: Purpose – Many organizations are outsourcing their information technology (IT) related services to a third party vendor for quite some time. However, the IT services industry including outsourcing is going through rapid changes with the increasing adoption of Cloud computing. The purpose of this paper is to compare global IT outsourcing with Cloud computing along with the evolution of traditional IT services.Design/methodology/approach – Cloud computing is a model for provisioning and consuming IT capabilities on a need and pay by use basis. This helps in shifting the cost structure from capital expenditure to operating expenditure and also helps the IT systems to be more agile. This innovative model of acquiring IT related services has made organizations revisit their infrastructure and platform services strategy and optimize their IT spending while improving overall agility. This paper compares global IT outsourcing with Cloud computing along with the evolution of traditional IT services.Findings – The ...

121 citations


Book ChapterDOI
04 Sep 2012
TL;DR: This chapter discusses various elements of Clouds which contribute to the total energy consumption and how it is addressed in the literature and the implication of these solutions for future research directions to enable green Cloud computing.
Abstract: Cloud computing is a highly scalable and cost-effective infrastructure for running HPC, enterprise and Web applications. However, the growing demand of Cloud infrastructure has drastically increased the energy consumption of data centers, which has become a critical issue. High energy consumption not only translates to high operational cost, which reduces the profit margin of Cloud providers, but also leads to high carbon emissions which is not environmentally friendly. Hence, energy-efficient solutions are required to minimize the impact of Cloud computing on the environment. In order to design such solutions, deep analysis of Cloud is required with respect to their power efficiency. Thus, in this chapter, we discuss various elements of Clouds which contribute to the total energy consumption and how it is addressed in the literature. We also discuss the implication of these solutions for future research directions to enable green Cloud computing. The chapter also explains the role of Cloud users in achieving this goal.

120 citations


Proceedings ArticleDOI
16 Apr 2012
TL;DR: Simulation results show that the proposed ILP is able to find low-cost solutions for short deadlines, while the proposed heuristics are effective when deadlines are larger.
Abstract: Cloud computing is being used to avoid maintenance costs and upfront investment, while providing elasticity to the available computational power in a pay-per-use basis. Customers can make use of the cloud as a software (SaaS), platform (PaaS), or infrastructure (IaaS) provider. When one customer utilizes an environment provided by a SaaS cloud, she is unaware of any details about the computational infrastructure where her requests are being processed. Therefore, such infrastructure can be composed of computational resources from a datacenter owned by the SaaS or its resources can be leased from a cloud infrastructure provider. In this paper we present an integer linear program (ILP) formulation for the problem of scheduling SaaS customer's workflows into multiple IaaS providers where SLA exists at two levels. In addition, we present heuristics to solve the relaxed version of the presented ILP. Simulation results show that the proposed ILP is able to find low-cost solutions for short deadlines, while the proposed heuristics are effective when deadlines are larger.

118 citations


Proceedings ArticleDOI
24 Jun 2012
TL;DR: This paper presents a federated multi-cloud PaaS infrastructure based on an open service model, shows how it can be deployed on top of thirteen existing IaaS/PaaS, and reports on three distributed SaaS applications developed with and deployed on this infrastructure.
Abstract: Cloud platforms are increasingly being used for hosting a broad diversity of services from traditional e-commerce applications to interactive web-based Ides. How-ever, we observe that the proliferation of offers by cloud providers raises several challenges. Developers will not only have to deploy applications for a specific cloud, but will also have to consider migrating services from one cloud to another, and to manage distributed applications spanning multiple clouds. In this paper, we present our federated multi-cloud PaaS infrastructure for addressing these challenges. This infrastructure is based on three foundations: i) an open service model used to design and implement both our multi-cloud PaaSand the SaaS applications running on top of it, ii) a configurable architecture of the federated PaaS, and iii) some infrastructure services for managing both our multi-cloud PaaS and the SaaS applications. We then show how this multi-cloud PaaS can be deployed on top of thirteen existing IaaS/PaaS. We finally report on three distributed SaaS applications developed with and deployed on our federated multi-cloud PaaS infrastructure.

Book ChapterDOI
18 Jun 2012
TL;DR: The learnings from studying software companies applying an innovation experiment system approach to product development are presented, illustrated with three cases from Intuit, the case study company.
Abstract: Traditional software development focuses on specifying and freezing requirements early in the, typically yearly, product development lifecycle. The requirements are defined based on product management's best understanding. The adoption of SaaS and cloud computing has shown a different approach to managing requirements, adding frequent and rigorous experimentation to the development process with the intent of minimizing R&D investment between customer proof points. This offers several benefits including increased customer satisfaction, improved and quantified business goals and the transformation to a continuous rather than waterfall development process. In this paper, we present our learnings from studying software companies applying an innovation experiment system approach to product development. The approach is illustrated with three cases from Intuit, the case study company.

Journal ArticleDOI
TL;DR: This paper proposes a new QoS-based workflow scheduling algorithm based on a novel concept called Partial Critical Paths (PCP), which tries to minimize the cost of workflow execution while meeting a user-defined deadline.

Journal ArticleDOI
01 Jun 2012
TL;DR: A service management framework implementation that supports on demand cloud provisioning and a novel monitoring framework that meets the demands of Cloud based applications are defined.
Abstract: Cloud computing is a promising paradigm for the provisioning of IT services. Cloud computing infrastructures, such as those offered by the RESERVOIR project, aim to facilitate the deployment, management and execution of services across multiple physical locations in a seamless manner. In order for service providers to meet their quality of service objectives, it is important to examine how software architectures can be described to take full advantage of the capabilities introduced by such platforms. When dealing with software systems involving numerous loosely coupled components, architectural constraints need to be made explicit to ensure continuous operation when allocating and migrating services from one host in the Cloud to another. In addition, the need for optimising resources and minimising over-provisioning requires service providers to control the dynamic adjustment of capacity throughout the entire service lifecycle. We discuss the implications for software architecture definitions of distributed applications that are to be deployed on Clouds. In particular, we identify novel primitives to support service elasticity, co-location and other requirements, propose language abstractions for these primitives and define their behavioural semantics precisely by establishing constraints on the relationship between architecture definitions and Cloud management infrastructures using a model denotational approach in order to derive appropriate service management cycles. Using these primitives and semantic definition as a basis, we define a service management framework implementation that supports on demand cloud provisioning and present a novel monitoring framework that meets the demands of Cloud based applications.

Patent
24 Jan 2012
TL;DR: In this article, a flow tagging technique includes tagging a data flow at a plurality of points in the data flow, such as a socket and a proxy manager API, to map network service usage activities to the appropriate initiating applications.
Abstract: A flow tagging technique includes tagging a data flow at a plurality of points in the data flow. For example, the data flow can be tagged at a socket and at a proxy manager API. By tagging the data flow at multiple points, it becomes possible to map network service usage activities to the appropriate initiating applications.

Proceedings Article
01 Jan 2012
TL;DR: This paper defines multi-tenancy and differentiates it from several related concepts and provides an overview of important architectural concerns and there mutual influences.
Abstract: Multi-tenant applications serve different customers with one application instance. This architectural style leverages sharing and economies of scale to provide cost efficient hosting. As multi-tenancy is a new concept, a common definition of the word and related concepts is not yet established and the architectural concerns are not fully understood. This paper provides an overview of important architectural concerns and there mutual influences. Beside that, it defines multi-tenancy and differentiates it from several related concepts.

DOI
03 Jun 2012
TL;DR: In this article, the authors present an approach for mapping software design to power consumption and present empirical results of the approach on different software implementations, comparing the power profiles of software using design patterns against software not using design pattern as a way to explore how high-level design decisions affect an application's energy usage.
Abstract: As the use of computers has grown, so too has concern about the amount of power they consume. Data centers, for example, are limited in scalability as they struggle with soaring energy costs from many large companies relying on fast, reliable, and round-the-clock computing services. On large-scale computing clusters, like data centers, even a small drop in power consumption can have large effects. Across computing contexts, reducing power consumed by computers has become a major focus. In this paper, we present a new approach for mapping software design to power consumption and present empirical results of the approach on different software implementations. In particular, we compare the power profiles of software using design patterns against software not using design patterns as a way to explore how high-level design decisions affect an application's energy usage. We show how mappings between software design and power consumption profiles can provide software designers and developers with useful information about the power behavior of the software they are developing. The goal is for software engineers to use this information in designing and developing more energy efficient solutions.

Journal ArticleDOI
TL;DR: In this article, an extensive survey of security and privacy issues in a cloud computing environment is presented, which aims to elaborate and analyze the numerous unresolved issues threatening the cloud computing adoption and diffusion affecting the various stake-holders associated with it.
Abstract: Computing holds the potential to eliminate the requirements for setting up of high-cost computing infrastructure for IT-based solutions and services that the industry uses. It promises to provide a flexible IT architecture, accessible through internet from lightweight portable devices. This would allow multi-fold increase in the capacity and capabilities of the existing and new software. In a cloud computing environment, the entire data resides over a set of networked resources, enabling the data to be accessed through virtual machines. Since these data-centres may be located in any part of the world beyond the reach and control of users, there are multifarious security and privacy challenges that need to be understood and addressed. Also, one can never deny the possibility of a server breakdown that has been witnessed, rather quite often in the recent times. There are various issues that need to be addressed with respect to security and privacy in a cloud computing environment. This extensive survey paper aims to elaborate and analyze the numerous unresolved issues threatening the cloud computing adoption and diffusion affecting the various stake-holders associated with it. Keywordsas a Service (SaaS), Platform as a Service (PaaS), Infrastructure as a Service (IaaS), Interoperability, Denial of Service (DoS), Distributed Denial of Service (DDoS), Mobile Cloud Computing (MCC), Optical Character Recognition (OCR), Community of Interest (COI).

Proceedings ArticleDOI
22 Jun 2012
TL;DR: The core concept of secured cloud computing is proposed, which is a cloud computing based on separate encryption and decryption services from the storage service and how they can be avoided.
Abstract: The concept of cloud computing is a very vast concept which is very efficient and effective security services. The cloud computing methodology is a conceptual based technology which is used widely now a day. But in data privacy protection and data retrieval control is one of the most challenging research work in cloud computing, because of users secrete data which is to be stored by user. An enterprise usually store data in internal storage and then tries to protect the data from other outside source. They also provide authentication at certain specific level. Cloud computing offers an innovative business model for organizations to adopt IT services without upfront investment. Despite the potential gains achieved from the cloud computing, the organizations are slow in accepting it due to security issues and challenges associated with it. Security is one of the major issues which hamper the growth of cloud. The idea of handing over important data to another company is worrisome; such that the consumers need to be vigilant in understanding the risks of data breaches in this new environment. This paper introduces a detailed analysis of the cloud computing security issues and challenges focusing on the cloud computing types and the service delivery types. This paper mainly proposes the core concept of secured cloud computing. It suggests the cloud computing based on separate encryption and decryption services from the storage service. Due to this increasing demand for more clouds there is an ever growing threat of security becoming a major issue. This paper shall look at ways in which security threats can be a danger to cloud computing and how they can be avoided.

Proceedings ArticleDOI
TL;DR: In this article, the authors identify open issues in autonomic resource provisioning and presents innovative management techniques for supporting SaaS applications hosted on clouds and present a conceptual architecture and early results evidencing the benefits of autonomic management of clouds.
Abstract: As Clouds are complex, large-scale, and heterogeneous distributed systems, management of their resources is a challenging task. They need automated and integrated intelligent strategies for provisioning of resources to offer services that are secure, reliable, and cost-efficient. Hence, effective management of services becomes fundamental in software platforms that constitute the fabric of computing Clouds. In this direction, this paper identifies open issues in autonomic resource provisioning and presents innovative management techniques for supporting SaaS applications hosted on Clouds. We present a conceptual architecture and early results evidencing the benefits of autonomic management of Clouds.

Proceedings ArticleDOI
12 Aug 2012
TL;DR: To foster experiments as a service in IR, this work presents a Web framework for experiments that addresses the outlined challenges and possesses a unique set of compelling features in comparison to existing solutions.
Abstract: With its close ties to the Web, the IR community is destined to leverage the dissemination and collaboration capabilities that the Web provides today. Especially with the advent of the software as a service principle, an IR community is conceivable that publishes experiments executable by anyone over the Web. A review of recent SIGIR papers shows that we are far away from this vision of collaboration. The benefits of publishing IR experiments as a service are striking for the community as a whole, and include potential to boost research profiles and reputation. However, the additional work must be kept to a minimum and sensitive data must be kept private for this paradigm to become an accepted practice. To foster experiments as a service in IR, we present a Web framework for experiments that addresses the outlined challenges and possesses a unique set of compelling features in comparison to existing solutions. We also describe how our reference implementation is already used officially as an evaluation platform for an established international plagiarism detection competition.

Proceedings ArticleDOI
24 Jun 2012
TL;DR: This paper introduces a novel QoS-driven approach for helping SaaS developers select the services for composing multi-tenant SAAS, which achievesSaaS providers' optimisation goals while fulfilling the end-users' different levels of QoS constraints.
Abstract: Cloud-based software applications (Software as a Service - SaaS) for multi-tenant provisioning have become a major development paradigm in Web engineering. Instead of serving a single end-user, a multi-tenant SaaS provides multiple end-users with the same functionality but with potentially different quality-of-service (QoS) values. The service selection for such a SaaS is a complex decision-making process which involves a number of stakeholders with different QoS requirements. SaaS developers need to compose services with different QoS values to meet end-users' different multidimensional QoS constraints for the SaaS. Furthermore, they also need to satisfy SaaS providers' optimisation goals for the SaaS, such as least resource cost and best system performance. Existing QoS-aware service selection approaches are oriented at a single tenant. They do not consider the characteristics of multi-tenant SaaS and hence are ineffective and inefficient when applied to compose multi-tenant SaaS. In this paper, we introduce a novel QoS-driven approach for helping SaaS developers select the services for composing multi-tenant SaaS, which achieves SaaS providers' optimisation goals while fulfilling the end-users' different levels of QoS constraints. The proposed approach is evaluated using an example SaaS synthetically generated based on a dataset of real-world Web services. Experimental results show that our approach significantly outperforms existing approaches in terms of both effectiveness and performance.

Patent
14 Sep 2012
TL;DR: In this paper, an application monitor and an application manager may be included with a multicomponent software application in a single installation package, and some of these services are provided through coordinated efforts of a system resource manager, a VM manager, an application Monitor and an Application Resource Manager.
Abstract: A virtualized computer platform is established and maintained by virtualization software on one or more physical computers. A multicomponent software application may execute on the virtualized computer platform, with different components of the application executing in different virtual machines, which are supported by the virtualization software. The virtualization software may also provide the provision of one or more services that may be beneficial to the operation of the multicomponent software application, such as automated provisioning, resource allocation, VM distribution, performance monitoring, resource management, high availability, backup, disaster recovery, alarms, security, etc. In some embodiments of the invention, some of these services are provided through coordinated efforts of a system resource manager, a VM manager, an application monitor and an application resource manager. In some of these embodiments, an application monitor and an application manager may be included with a multicomponent software application in a single installation package.

Proceedings ArticleDOI
01 Mar 2012
TL;DR: This paper introduces a comber approach for security services called filtering tree, which has five filters to detect and resolve XML and HTTP DDoS attack.
Abstract: Cloud computing is an internet based pay as use service which provides three layered services (Software as a Service, Platform as a Service and Infrastructure as a Service) to its consumers on demand. These on demand service facilities provide to its consumers in multitenant environment but as facility increases complexity and security problems also increase. Here all the resources are at one place in data centers. Cloud uses public and private APIs (Application Programming Interface) to provide services to its consumers in multitenant environment. In this environment Distributed Denial of Service attack (DDoS), especially HTTP, XML or REST based DDoS attacks may be very dangerous and may provide very harmful effects for availability of services and all consumers will get affected at the same time. One other reason is that because the cloud computing users make their request in XML then send this request using HTTP protocol and build their system interface with REST protocol such as Amazon EC2 or Microsoft Azure. So the threaten coming from distributed REST attacks are more and easy to implement by the attacker, but to security expert very difficult to resolve. So to resolve these attacks this paper introduces a comber approach for security services called filtering tree. This filtering tree has five filters to detect and resolve XML and HTTP DDoS attack.

Proceedings ArticleDOI
01 Nov 2012
TL;DR: This paper identifies open issues in autonomic resource provisioning and presents innovative management techniques for supporting SaaS applications hosted on Clouds and early results evidencing the benefits of autonomic management of Clouds are presented.
Abstract: As Clouds are complex, large-scale, and heterogeneous distributed systems, management of their resources is a challenging task. They need automated and integrated intelligent strategies for provisioning of resources to offer services that are secure, reliable, and cost-efficient. Hence, effective management of services becomes fundamental in software platforms that constitute the fabric of computing Clouds. In this direction, this paper identifies open issues in autonomic resource provisioning and presents innovative management techniques for supporting SaaS applications hosted on Clouds. We present a conceptual architecture and early results evidencing the benefits of autonomic management of Clouds.

Patent
06 Aug 2012
TL;DR: In this article, an Internet-based interface is provided as a single portal for monitoring and managing the use of SaaS applications or cloud computing services, where objects and the state of these objects including all associated attributes related to the applications or Cloud computing services are stored in databases associated with the Internet based interface.
Abstract: An apparatus, system, method and program providing a multi-tenant software as a service (SaaS) application or cloud computing service that manages and monitors the use of other SaaS applications or cloud computing services via a common connection and database framework. An Internet-based interface is provided as a single portal for monitoring and managing the use of SaaS applications or cloud computing services. Objects and the state of these objects including all associated attributes related to the SaaS applications or cloud computing services are stored in databases associated with the Internet-based interface. The Internet-based interface also provides a social networking infrastructure and an application exchange infrastructure that allows sharing of information related to the SaaS applications or cloud computing services.

Patent
10 Jan 2012
TL;DR: A software-based method and system to provide a secure user interface on multiple and diverse electronic computing devices with a customized and secure dashboard feature is presented in this paper, which can be used in management and operations that use computer based software, data management, creative processes and communication systems.
Abstract: A software-based method and system to provide a secure user interface on multiple and diverse electronic computing devices with a customized and secure dashboard feature. The systems and methods simultaneously integrate internally generated software utilities of an enterprise with externally accessed software operating in a ‘cloud computing’ environment. The systems and methods can be used in management and operations that use computer based software, data management, creative processes and communication systems. The systems and methods reduce the requirement for additional programming to integrate or interchange equivalent and independently developed software for use within an enterprise. The systems and methods permit social network communications between members of an enterprise and an external community. The security features of the user interface portal permit collaborations between parties in an external community and enterprise members that can develop new processes that remain proprietary to the enterprise and parties of an external community.

Proceedings ArticleDOI
25 Jun 2012
TL;DR: This paper proposes three different types of novel metrics for quantifying the performance isolation of cloud-based systems and a simulation-based case study applying these metrics in the context of a Softwareas-a-Service (SaaS) scenario where different customers (tenants) share one single application instance.
Abstract: The cloud computing paradigm enables the provision of costefficient IT-services by leveraging economies of scale and sharing data center resources efficiently among multiple independent applications and customers. However, the sharing of resources leads to possible interference between users and performance problems are one of the major obstacles for potential cloud customers. Consequently, it is one of the primary goals of cloud service providers to have different customers and their hosted applications isolated as much as possible in terms of the performance they observe.To make different offerings, comparable with regards to their performance isolation capabilities, a representative metric is needed to quantify the level of performance isolation in cloud environments. Such a metric should allow to measure externally by running benchmarks from the outside treating the cloud as a black box. In this paper, we propose three different types of novel metrics for quantifying the performance isolation of cloud-based systems and a simulation-based case study applying these metrics in the context of a Softwareas-a-Service (SaaS) scenario where different customers (tenants) share one single application instance. We consider four different approaches to achieve performance isolation and evaluate them based on the proposed metrics. The results demonstrate the effectiveness and practical usability of the proposed metrics in quantifying the performance isolation of cloud environments.

Journal ArticleDOI
TL;DR: The paper presents an efficient cloud resource provisioning approach that includes two sub-algorithms at different levels: interaction between the SAAS user and SaaS provider at the application layer and interaction Between the Saas provider and cloud resource provider atThe resource layer.
Abstract: The paper presents an efficient cloud resource provisioning approach. The Software as a Service (SaaS) provider leases resources from cloud providers and also leases software as services to SaaS users. The SaaS providers aim at minimizing the payment of using VMs from cloud providers, and want to maximize the profit earned through serving the SaaS users' requests. The SaaS providers also guarantee meeting quality of service (QoS) requirements of the SaaS users. The cloud provider is to maximize the profit without exceeding the upper bound of energy consumption of cloud provider for provisioning virtual machines (VMs) to the SaaS provider. The SaaS users purpose to obtain the optimized QoS to accomplish their jobs with a limited budget and deadline. The proposed optimal cloud resource provisioning algorithm includes two sub-algorithms at different levels: interaction between the SaaS user and SaaS provider at the application layer and interaction between the SaaS provider and cloud resource provider at the resource layer. Simulations are conducted to compare the performance of proposed cloud resource provisioning algorithm with related work.

Journal ArticleDOI
TL;DR: It is found that the lock-in strategy is actually counterproductive in competing against open-source software, and giving customers the freedom of choice may end up benefiting the proprietary software vendor.
Abstract: Open-source software poses a serious challenge to proprietary software vendors. “Lock in customers” seems a tempting strategy for proprietary software vendors, who attempt to lock in customers by creating switching costs. This paper examines whether such a lock-in strategy will indeed benefit proprietary software vendors facing competition from open-source software, who can credibly commit future prices. Developing a two-period duopoly model in which software products are differentiated and customers are heterogeneous, we find that the lock-in strategy is actually counterproductive in competing against open-source software. In fact, giving customers the freedom of choice may end up benefiting the proprietary software vendor. In terms of the broader effect, we find that lock-in reduces overall social welfare, but certain customers may actually be better off with it. Finally, we show that the lock-in strategy works differently for different types of customers in the software market (i.e., foresighted versus myopic customers). This suggests that customer behavior could significantly alter the equilibrium strategy of software vendors.