Survivability of Information System

All information systems cannot be made secure and completely reliable especially when faced with major accidents, environmental disturbances, and deliberate information warfare attacks. From points of view of communication, this paper concentrates on using mathematical method to measure the survivability of an information system after a few communication links of this information system are destroyed by physical attacks. In addition to survivability of information system, survivability of components of information system, for example, survivability of one node, survivability between two nodes, survivability of information subsystem, survivability between two independent information subsystems, are also dealt with in this paper