Date Added: Jul 2011
A cloud computing infrastructure typically consists of a number of sites that house servers and are connected to the Internet. Its operation critically depends both on cyber components, including servers and routers, and physical components, including fiber and power routes. Both types of components are subject to attacks of different kinds and frequencies, which must be accounted for the initial provisioning and subsequent operation of the infrastructure. The cyber and physical components may be individually attacked and defended, and the infrastructure is required to provide an aggregate computational capacity C.