Least Effort Strategies for Cybersecurity

Abstract

Cybersecurity is an issue of increasing concern since the events of September 11th. Many questions have been raised concerning the security of the Internet and the rest of the US's information infrastructure. This paper begins to examine the issue by analyzing the Internet's autonomous system (AS) map. Using the AS map, malicious infections are simulated and different defense strategies are considered in a cost benefit framework. The results show that protecting the most connected nodes provides significant gains in security and that after the small minority of most connected nodes are protected there are diminishing returns for further protection. Although if parts of the small minority are not protected, such as non-US networks, protection levels are significantly decreased.