Improving System Reliability Against Rational Attacks Under Given Resources

System reliability has always been a challenging issue for many systems. In order to achieve high reliability, redundancy and voting schemes are often used to tolerate unintentional component failures. For unintentional failures caused by, for instance, normal wear-outs, hardware failures, or software bugs, etc., adding more redundancies often improves a system's reliability. However, when attack-caused failures exist, the number of redundant components and the number of participating voting entities may not be positively proportional to system reliability. In this paper, we study system reliability and system defense strategies when the system is under rational attacks. In particular, we analyze how defense and attack strategies may impact system reliability when both the defender and attacker are given a fixed amount of resources that can only be used for adding camouflaging components or enhancing existing components' cyber protection by defenders, or selecting a subset of components to attack by attackers, respectively. We also present an algorithm to decide the optimal defense strategy in fighting against rational attacks.