Optimal resource allocation for protecting system availability against random cyber attacks

Distributed systems usually provide services with varying criticalities. Failures of core services lead to catastrophic consequences to the system. Maintaining system core services´ availability with limited resources has become a challenging issue, especially when system operates in an adversary environment and face malicious under attack. This paper discusses the attacker-defender problem and analyzes how to allocate resources to maximize system availability, especially the core services availability. In our model, the defender seeks to maintain maximum system availability for a given period of time, and does so by distributing defensive resources to component protection enhancement, creation of redundant components, and camouflaged components deployment. We assume that the attacker has no knowledge about the system configuration, and hence randomly attacks different nodes in the system. We formulate this attacker-defender problem as a defender´s optimization problem and present an algorithm that optimally allocates system resource to achieve maximum system availability.