云计算：面向IT业与科学研究的分布式互联网计算（Cloud.Computing.Distributed.Intern.pdf

本帖最后由 post2007 于 2011-10-24 21:02 编辑

Cloud Computing Distributed Internet Computing for IT and Scientific Research
云计算：面向IT业与科学研究的分布式互联网计算


One vision of 21st century computing is that users will access Internet services over lightweight portable devices rather than through some  descendant  of  the  traditional desktop PC. Because users won't have (or be interested in) powerful machines,who will supply the computing power?The answer to this question lies with cloud computing.
21世纪互联网计算的一个景象，是用户将通过轻便的便携式设备而不是传统台式PC机的某种派生设备来接入互联网业务。由于用户不会拥有（或不感兴趣）计算功能强大的机器，那么谁会提供这种计算能力？对此问题的回答是云计算。

Cloud computing is a recent trend in IT that moves computing and data away from desktop and portable PCs into large data centers. It refers  to applications delivered as services over the Internet as well as to the actual cloud infrastructure 一namely,the hardware and systems software in data centers that provide these services.
云计算是近来的发展趋势，是一种将互联网计算与数据存储从台式电脑与便携式PC移植到大数据中心的IT技术。它系指互连网上各种业务的交付使用和真实的云基础设施，即提供这些业务的数据中心的硬件与系统软件。

The key driving forces behind cloud computing are the ubiquity of broadband and wireless networking, falling storage costs, and progressive improvements in Internet computing software.Cloud-service clients will be able to add more  capacity  at peak demand,reduce costs, experiment with new services, and remove unneeded capacity,whereas service providers will increase utilization via multiplexing, and allow for larger investments in software and hardware.
云计算后面重要的推动力量，是无处不在的宽带与无线联网，下跌的存储成本与互联网计算软件持续不断的改进。云计算业务代理将添加更多的峰值需求容量，降低成本，体验新的业务并且剔除不需要的功能，业务供应商将通过多路复用增加网络的利用率，并且会对软硬件有大量的各种投资。

Currently, the main technical underpinnings of cloud computing infrastructures and services include virtualization,service一oriented software, grid computing technologies, management of large facilities, and power efficiency. Consumers purchase such services in the form of  infrastructure一as一a-service (IaaS),platform一as一a一service  (PaaS), or software一as一a一service (SaaS) and sell value-added services (such as utility services)to users. Within the cloud, the laws of probability give service providers great leverage through statistical multiplexing of varying workloads and easier management一a single software installation can cover many users' needs.
目前，云计算体系架构与业务的主要技术支撑包括虚拟技术，面向业务的软件、网格计算技术、大联网设施的管理与能量利用效率技术。消费者将会按基础设施即业务(IaaS)、平台即业务(PaaS)、或软件即业务(SaaS)的形式购买这样的业务，并且对用户出售增值业务（诸如业务使用）。在云内部，概率定理将通过可变网络负荷统计意义上的多路复用，给业务供应商提供大的杠杆作用并且使管理简易可行——安装单个软件即可满足众多的用户需求。