Framework Of The Survivability Of Network Systems And Network Survivability Quantitative Assessment

Over the years, with the rapid development of Internet technologies, network infrastructure, network activity undergoes a profound change. Inevitable malicious attacks in the more open network paradigm, as well as the unexpected failures to network components, have a significant impact to the network operation. In such circumstances, it is impossible to build a network system that has absolute security. People shifted their attentions from absolute secure to limited fault and intrusion tolerance. Network survivability emphasizes a network system to provide essential services and fulfill their missions in the presence of attacks, failures or accidents and recover full services in a timely manner.This thesis firstly studies the survivability of network and its relevant areas, introduces the researching work's history and development, classification, key technology and current situation et al.Then, a framework of survivable network system is proposed. The framework based on component redundancy and method redundancy, IDS and adaptation are organized into the framework.Quantification of a network's survivability is important. Semi-Markov-Process method is used to evaluate the survivability. Recognition, resistance, recovery, availability, integrity and confidentiality are proposed to be the survivability quantification index parameters. Considering different threats result in network's different reactions, intrusion scenario model and fault/accident scenario model are built and their survivability is quantified.SMP method is used to quantify the framework proposed before, and proved the principle that using redundancy, adaptation and randomness to build survivable network is effective. Finally, practicability and effectiveness of SMP method is discussed.