移动云计算

在延伸云到网络边缘（终端）的趋势下,移动云计算正在成为一个新兴的云服务模型。它包括许多与用户密切相关移动设备。它们直接参与到很多云的工作中,使得云边界直接延伸到了整个物理网络系统中。在这篇文章中,我们将介绍什么是移动云计算,包括其范围,目前的发展和研究的挑战。     

Cloud computing — The business perspective

The evolution of cloud computing over the past few years is potentially one of the major advances in the history of computing. However, if cloud computing is to achieve its potential, there needs to be a clear understanding of the various issues involved, both from the perspectives of the providers and the consumers of the technology. While a lot of research is currently taking place in the technology itself, there is an equally urgent need for understanding the business-related issues surrounding cloud computing. In this article, we identify the strengths, weaknesses, opportunities and threats for the cloud computing industry. We then identify the various issues that will affect the different stakeholders of cloud computing. We also issue a set of recommendations for the practitioners who will provide and manage this technology. For IS researchers, we outline the different areas of research that need attention so that we are in a position to advice the industry in the years to come. Finally, we outline some of the key issues facing governmental agencies who, due to the unique nature of the technology, will have to become intimately involved in the regulation of cloud computing.     

Challenges in migrating legacy software systems to the cloud — an empirical study

Moving existing legacy systems to cloud platforms is a difficult and high cost process that may involve technical and non-technical resources and challenges. There is evidence that the lack of understanding and preparedness of cloud computing migration underpin many migration failures in achieving organisations’ goals. The main goal of this article is to identify the most important challenging activities for moving legacy systems to cloud platforms from a perspective of reengineering process. Through a combination of a bottom-up and a top-down analysis, a set of common activities is derived from the extant cloud computing literature. These are expressed as a model and are validated using a population of 104 shortlisted and randomly selected domain experts from different industry sectors. We used a Web-based survey questionnaire to collect data and analysed them using SPSS Sample T-Test. The results of this study highlight the most important and critical challenges that should be addressed by various roles within a legacy to cloud migration endeavour. The study provides an overall understanding of this process including common occurring activities, concerns and recommendations. In addition, the findings of this study constitute a practical guide to conduct this transition. This guide is platform agnostic and independent from any specific migration scenario, cloud platform, or an application domain.     

无服务器计算技术研究综述

随着云计算的发展以及传统行业的转型，不断提高的技术要求与日益旺盛的市场需求使传统的应用软件开发模式面临挑战。同时，人们正在探索新一代的更经济、更有潜力的云服务模式。无服务器计算依托容器技术，提供了高并发、高兼容的特性，为开发者隐藏了底层服务器的细节，同时采取了更经济的按调用次数或时间计费的服务运营模式，引起了广泛的关注。首先，介绍无服务器计算的概念，并介绍其系统架构与技术特性。然后，介绍无服务器计算在科研、开源社区与工业届的研究现状。随后，列举无服务器计算在众多应用领域的实施案例。最后，阐述无服务器计算技术当前面临的挑战。     

A user-space file system for on-demand legacy desktop software

Some user-level virtualization technologies have been used to convert legacy software (like the existing Windows desktop applications) into the on-demand software without any modification. To give the client a friendly and compatible method to access on-demand legacy software across the Internet, this paper presents a clientend file system for this usage case. It is a Windows user-space file system based on the cloud storage (where the on-demand software is stored), which converts the local file system acce...     

IC cloud: Enabling compositional cloud

Cloud computing has attracted great interest from both academic and industrial communities. Different paradigms, architectures and applications based on the concept of cloud have emerged. Although many of them have been quite successful, efforts are mainly focusing on the study and implementation of particular setups. However, a generic and more flexible solution for cloud construction is missing. In this paper, we present a composition-based approach for cloud computing (compositional cloud) using Imperial College Cloud (IC Cloud) as a demonstration example. Instead of studying a specific cloud computing system, our approach aims to enable a generic framework where various cloud computing architectures and implementation strategies can be systematically studied. With our approach, cloud computing providers/adopters are able to design and compose their own systems in a quick and flexible manner. Cloud computing systems will no longer be in fixed shapes but will be dynamic and adjustable according to the requirements of different application domains.     

云计算时代的平台战略

随着Google的崛起,云计算概念悄然进入大家的视野,计算技术发展的重点已经狄信息处理逐步过渡到了信息服务,打造信息服务平台已经变成云计算时代的主旋律。文章简单介绍了云计算的基本概念,云计算的主要类型,重点分析和研究了云计算时代平台战略的主要组成和关键技术．提出了平台战略的核心思想。     

Cloud based management and control system for smart communities: A practical case study

In this study, the implementation of cloud based smart community management and control system was undertaken. SmartComunity.in is a flexible platform to manage and control the affairs of a condominium or society with thorough participation, visibility and transparency. Our research is the first attempt to study one such real life system of cloud based control and management in a smart housing community in India. There is a dearth of exploratory studies that explain the diffusion and adoption of cloud computing in different contexts and from a multiple stakeholder perspective. So, the main contribution of our research is to understand the framework of cloud computing based smart community services in India and the emerging cloud computing ecosystems. This research has wide ranging implications on the future of Internet of Things, and can be extended to elderly health and support, energy efficient systems and smart cities.     

基于可信第三方实现多云平台的交互和选择

随着云计算商业模式的成功推进,形成了三大主流的云计算服务模式:平台即服务、软件即服务和基础架构即服务。传统行业的供应商纷纷加入云计算的队伍。但由于激烈的竞争环境,使得云计算的标准化道路举步维艰,致使跨平台的交互和移植难以实现。同时,由于对不同的云平台没有形成统一可信的评价标准,使得众多的平台服务让用户无从选择。本文通过具体分析各种应用场景对跨平台服务的需求,得出构建"跨平台即服务"模式的必要性和必然性,提出利用可信第三方来实现"跨平台即服务"模式,给出跨平台的数据交互和移植行为在可信第三方监控下的规范化流程,并提出以可信第三方为中心的云平台安全和信誉评价标准,为企业选择合适的云平台提供参考。     

面向DaaS的隐私保护机制研究综述

DaaS是基于云基础设施对外提供数据库服务的云服务模式, 能有效地解决个人和企业处理海量数据所带来的存储、管理压力, 但隐私泄露极大地阻碍了DaaS的发展, 如何增强现有DaaS模式的隐私保护成为亟需解决的问题。首先通过文献分析的方法剖析了DaaS的服务框架及其隐私泄露模型, 接着对DaaS中实现委托数据的机密性、对机密数据查询过程中的隐私保护及查询结果的验证、委托数据完整性验证过程中隐私保护三个方面的发展现状进行了综合分析。通过分析得出, 现有的隐私保护方法对DaaS中数据更新和查询效率方面的支持及其实用性都存在不同程度的缺陷, 如何设计高效的机密性算法和保护隐私的数据查询及查询结果验证仍是未来研究的重点。最后展望了未来的研究方向。     

A semantic interoperability framework for software as a service systems in cloud computing environments

In cloud computing environments in software as a service (SaaS) level, interoperability refers to the ability of SaaS systems on one cloud provider to communicate with SaaS systems on another cloud provider. One of the most important barriers to the adoption of SaaS systems in cloud computing environments is interoperability. A common tactic for enabling interoperability is the use of an interoperability framework or model. During the past few years, in cloud SaaS level, various interoperability frameworks and models have been developed to provide interoperability between systems. The syntactic interoperability of SaaS systems have already been intensively researched. However, not enough consideration has been given to semantic interoperability issues. Achieving semantic interoperability is a challenge within the world of SaaS in cloud computing environments. Therefore, a semantic interoperability framework for SaaS systems in cloud computing environments is needed. We develop a semantic interoperability framework for cloud SaaS systems. The capabilities and value of service oriented architecture for semantic interoperability within cloud SaaS systems have been studied and demonstrated. This paper is accomplished through a number of steps (research methodology). It begins with a study on related works in the literature. Then, problem statement and research objectives are explained. In the next step, semantic interoperability requirements for SaaS systems in cloud computing environments that are needed to support are analyzed. The details of the proposed semantic interoperability framework for SaaS systems in cloud computing environments are presented. It includes the design of the proposed semantic interoperability framework. Finally, the evaluation methods of the semantic interoperability framework are elaborated. In order to evaluate the effectiveness of the proposed semantic interoperability framework for SaaS systems in cloud computing environments, extensive experimentation and statistical analysis have been performed. The experiments and statistical analysis specify that the proposed semantic interoperability framework for cloud SaaS systems is able to establish semantic interoperability between cloud SaaS systems in a more efficient way. It is concluded that using the proposed framework, there is a significant improvement in the effectiveness of semantic interoperability of SaaS systems in cloud computing environments.     

云存储应用的现状、挑战、展望、创新及探讨

云存储是基于网络宽带下的数据存储服务,它将改变个人和企业的数据存储方式。针对云存储应用的现状及挑战,文章对其未来进行了展望和探讨,并对云存储应用进行了归纳,列举了当前知名云存储产品的特点及运营状况。同时根据云存储应用的现状,重点探讨了云存储应用所面临的挑战,对云存储应用的前景进行了展望,然后详述了云存储行业的数据迁移服务Backup Box。最后,重点提出了对云存储行业的四点感悟。     

私有云平台服务能力检测方法

针对现阶段使用私有云评测方法缺失所导致搭建私有云供需不匹配的问题,提出了一种自适应、可扩展的私有云系统能力检测方法,可对基础设施即服务（IaaS）云计算系统能力进行评测。首先,通过私有云应用程序接口动态扩展虚拟机数量;然后,通过性能特征模型选取虚拟机所需配置的硬件信息和操作系统类别,并根据用户的需求差异使用不同的负载模型,形成相应的模拟运行环境;最后,使用云计算服务等级协议（SLA）作为测试标准来衡量私有云服务能力。使用所提方法对Openstack开源私有云平台的能力进行了评测,实验结果表明,所提方法可以准确得出私有云服务能力,结果和用户实测一致。该方法负载生成成本更低,测试效率更高。并将该方法与Openstack自带的组件Rally进行对比,拓展性和负载动态模拟有很大的改进。     

云计算环境中SaaS的接入控制和调度策略研究

SaaS是一种基于网络的软件应用模式,是服务提供商将应用软件统一部署在自己的服务器上,用户根据自己的实际需要,通过互联网向服务提供商订购并支付自己所需的服务。在未来,SaaS模式是占主导地位的云服务模型。文中阐述SaaS的基本概念,介绍了SaaS的参考结构以及服务流程,分析概括了不同类型的服务要求的接人控制策略,总结了不同性能要求作业的调度策略,最后结合已有的云计算环境下的SaaS接入控制和调度策略研究成果,展望了未来的研究方向和亟待解决的关键问题。     

Legacy information systems: issues and directions

A legacy information system represents a massive, long-term business investment. Unfortunately, such systems are often brittle, slow and non-extensible. Capturing legacy system data in a way that can support organizations into the future is an important but relatively new research area. The authors offer an overview of existing research and present two promising methodologies for legacy information system migration     

Cloudow:一种基于用户层虚拟化的软件即服务模式运行系统

"软件即服务(SaaS)"是一种通过网络发布与使用软件的新模式,在很大程度上消除了用户购买、维护与升级应用程序的需要,被认为是软件未来的主流应用模式之一.本文提出了一种新的支持现有Windows桌面软件的SaaS模式并实现了其原型系统Cloudow:用户可以在任意的联网兼容计算机上按需运行现有的Windows软件(无需安装),且软件的个性化配置可以被保留以便下次使用时恢复.Cloudow使用用户层虚拟化技术解决了软件无需安装便能运行的问题,并通过用户层文件系统设计实现了软件在网络环境下的透明使用.与现有的基于远程虚拟机计算或者基于Web应用的SaaS模式相比,Cloudow能够直接支持现有软件的服务端存储/客户端运行模式,无需修改代码,较好地兼顾了软件兼容性与性能.同时,为尽可能降低Internet环境所带来的远程数据访问延迟,Cloudow大量采用了元数据/数据/文件预取与缓存策略,显著提高了实际部署中的应用性能;测试表明,因为采用了这些优化策略,对于很多常用的Windows桌面应用而言,在Cloudow下额外运行时间开销平均为12%到20%.     

软件授权技术的研究

软件授权是软件保护技术的延伸与发展。首先对软件保护技术进行了简单的分析和概括。在此基础上重点介绍了软件授权技术,分析了最新发展的云授权和软件即服务（SaaS）技术的特点以及需要解决的问题。最后对虚拟化技术的应用给软件授权带来的新问题进行了探讨。通过对各种问题引发原因的分析,得出SaaS作为一种创新的商业模式,只要能保证使用者的安全性,SaaS将会解决软件授权目前面临的许多问题。目的是对软件授权技术进行全面的分析与研究,指出软件授权技术面临的新问题以及今后的发展方向。     

ContainerCloudSim: An environment for modeling and simulation of containers in cloud data centers

Containers are increasingly gaining popularity and becoming one of the major deployment models in cloud environments. To evaluate the performance of scheduling and allocation policies in containerized cloud data centers, there is a need for evaluation environments that support scalable and repeatable experiments. Simulation techniques provide repeatable and controllable environments, and hence, they serve as a powerful tool for such purpose. This paper introduces ContainerCloudSim, which provides support for modeling and simulation of containerized cloud computing environments. We developed a simulation architecture for containerized clouds and implemented it as an extension of CloudSim. We described a number of use cases to demonstrate how one can plug in and compare their container scheduling and provisioning policies in terms of energy efficiency and SLA compliance. Our system is highly scalable as it supports simulation of large number of containers, given that there are more containers than virtual machines in a data center. Copyright © 2016 John Wiley & Sons, Ltd.     

基于云计算的工商办公自动化系统的设计与实现

办公自动化系统是为适应现代无纸化及网络化办公的趋势,更好地服务于现代办公操作,基于B/S模式而开发的一套应用于工商系统的办公自动化系统.系统在设计与实现上基于云服务模式,将系统构架分为基础设施层(IaaS)、系统平台层(PaaS)、应用服务层(SaaS).基于云服务平台的设计,能够提升系统的可靠性和数据存储安全性,实现硬件资源共享和动态调整,实现应用弹性部署,为各机关提供个性化定制服务,降低运维成本、实现节能减排,并提升技术的先进性,并奠定业务的可扩展基础.     

基于云计算的网络教育培训系统研究与实现

针对电网企业网络教育培训系统集中部署产生的访问峰值问题,提出基于云计算建设动态可扩展应用系统的设计方案,并给出系统架构,包括动态集群扩展、基于订阅-发布模式的共享消息总线的系统集成、系统数据解耦等关键技术。通过搭建实验环境,模拟大并发压力下动态调配资源支撑业务需求的场景,结果证明,基于云计算的网络教育培训系统能够满足大并发访问压力下的动态资源需求,保证用户的访问体验。