云计算同时带来巨大的新商业机会,所以被称为继大型机、个人电脑和互联网之后的第四次IT革命在全球IT界,云计算正在引起一场深刻的革命。“云计算”一词由美国谷歌公司于2006年首次提出,是指通过统一灵活调用各种网络资源,将计算、存储和网络等IT资源进行整合、抽象后,以按需、易扩展的方式通过互联网提供给用户。云计算有两个显著特点:一是I CT(信 Cloud computing brings huge new business opportunities at the same time, so it is called the fourth IT revolution following the mainframe, PC and Internet. Cloud computing is causing a profound revolution in the global IT community. The term “cloud computing” was first proposed by Google in 2006 in the United States. It refers to the integration of IT resources such as computing, storage and networking by unifying and flexibly invoking various network resources. After abstracting, the term “cloud computing” is easily extensible The way to provide users through the Internet. Cloud computing has two salient features: First, I CT (letter