Critical infrastructure protection under imperfect attacker perception

This paper considers the problem of allocating nite resources among the elements of a critical infrastructure system in order to protect it from antagonistic attacks. Previous studies have assumed that the attacker has complete information about the utilities associated with attacks on each element. In reality, it is likely that the attacker's perception of the system is not as precise as the defender's, due to geographical separation from the system, secrecy, surveillance, complex system properties etc. As a result, the attacker's actions may not be those anticipated under the assumption of complete information. We present a modeling framework that incorporates imperfect attacker perception by introducing random observation errors in a previously studied baseline model. We analyze how the perceptive ability a ects attack probabilities and the defender's disutility and optimal resource allocation. We show e.g. that the optimal resource allocation may di er signi cantly from the baseline model, that a less perceptive attacker may cause greater disutility for the defender, and that increasing the investment in an element can increase the expected disutility even in a zero-sum situation.