The topology of covert conflict

TL;DR

This paper develops an evolutionary game theory framework to analyze how different attack and defense strategies impact network topology, revealing that complex defenses like delegation and clique structures are more effective against sophisticated attacks.

Contribution

It extends static network attack analysis to a dynamic, strategic setting, introducing a game-theoretic model that evaluates various defense mechanisms against different attack strategies.

Findings

Clique-based defenses are highly effective against vertex-order attacks.

Centrality-based attacks outperform vertex-order attacks against clique defenses.

Complex strategies like delegation combined with clique defenses resist centrality attacks better.

Abstract

Often an attacker tries to disconnect a network by destroying nodes or edges, while the defender counters using various resilience mechanisms. Examples include a music industry body attempting to close down a peer-to-peer file-sharing network; medics attempting to halt the spread of an infectious disease by selective vaccination; and a police agency trying to decapitate a terrorist organisation. Albert, Jeong and Barabasi famously analysed the static case, and showed that vertex-order attacks are effective against scale-free networks. We extend this work to the dynamic case by developing a framework based on evolutionary game theory to explore the interaction of attack and defence strategies. We show, first, that naive defences don't work against vertex-order attack; second, that defences based on simple redundancy don't work much better, but that defences based on cliques work well; third, that attacks based on centrality work better against clique defences than vertex-order attacks do; and fourth, that defences based on complex strategies such as delegation plus clique resist centrality attacks better than simple clique defences. Our models thus build a bridge between network analysis and evolutionary game theory, and provide a framework for analysing defence and attack in networks where topology matters. They suggest definitions of efficiency of attack and defence, and may even explain the evolution of insurgent organisations from networks of cells to a more virtual leadership that facilitates operations rather than directing them. Finally, we draw some conclusions and present possible directions for future research.