Network defense strategies for maximization of network survivability

The Internet has brought about several threats of information security to individuals and cooperates. It is difficult to keep a network completely safe because cyber attackers can launch attacks through networks without limitations of time and space. As a result, it is an important and critical issue be able to efficiently evaluate network survivability. In this paper, an innovative metric called the Degree of Disconnectivity (DOD) is proposed, which is used to evaluate the damage level of the network. A network attack-defense scenario is also considered in this problem, in which the attack and defense actions are composed by many rounds with each round containing two stages. In the first stage, defenders deploy limited resources on the nodes resulting in attackers needing to increase attack costs to compromise the nodes. In the second stage, the attacker uses his limited budget to launch attacks, trying to maximize the damage of the network. The Lagrangean Relaxation Method is applied to obtain optimal solutions for the problem.