二十世纪末的网络主要是为了实现静态应用和电子邮件应用而设计的,往往只是针对某一特殊的应用需求。而目前随着承载业务的变化和交换技术的发展,网络应用呈现出动态的、可预测的新特点,如云网络。云网 The late twentieth-century network was designed primarily for static applications and e-mail applications, often targeting only a specific application. At present, with the change of bearer services and the development of exchange technologies, network applications present new dynamic and predictable features such as cloud networks. Cloud network