How do you defend a network?

• 成果类型: Article
• 署名作者: Dziubinski, Marcin; Goyal, Sanjeev
• 署名单位: University of Warsaw; University of Cambridge; University of Cambridge
• 刊物名称: THEORETICAL ECONOMICS
• ISSN/ISSBN: 1933-6837
• DOI: 10.3982/TE2088
• 发表日期: 2017-01-01
• 页码: 331-376
• 关键词: infrastructure; costs of conflict; windmill graph; attack; DEFENSE

摘要

Modern economies rely heavily on their infrastructure networks. These networks face threats ranging from natural disasters to human attacks. As networks are pervasive, the investments needed to protect them are very large; this motivates the study of targeted defense. What are the key nodes to defend to maximize functionality of the network? What are the incentives of individual nodes to protect themselves in a networked environment and how do these incentives correspond to collective welfare? We first provide a characterization of optimal attack and defense in terms of two classical concepts in graph theory: separators and transversals. This characterization permits a systematic study of the intensity of conflict (the resources spent on attack and defense) and helps us identify a new class of networkswindmill graphsthat minimize conflict. We then study security choices by individual nodes. Our analysis identifies the externalities and shows that the welfare costs of decentralized defense in networks can be very large.