Enhancing network robustness for malicious attacks

TL;DR

This paper introduces a new link-robustness measure and a hybrid algorithm to improve network resilience against combined node and link failures, demonstrating enhanced robustness in realistic attack scenarios.

Contribution

It proposes a link-robustness index and a hybrid optimization algorithm to enhance network robustness against both node and link failures, addressing limitations of previous node-focused methods.

Findings

Hybrid algorithm improves robustness against mixed attacks

Link-robustness index differs from node-robustness

Enhanced robustness with economical link modifications

Abstract

In a recent work [Proc. Natl. Acad. Sci. USA 108, 3838 (2011)], the authors proposed a simple measure for network robustness under malicious attacks on nodes. With a greedy algorithm, they found the optimal structure with respect to this quantity is an onion structure in which high-degree nodes form a core surrounded by rings of nodes with decreasing degree. However, in real networks the failure can also occur in links such as dysfunctional power cables and blocked airlines. Accordingly, complementary to the node-robustness measurement ($R_{n}$), we propose a link-robustness index ($R_{l}$). We show that solely enhancing $R_{n}$ cannot guarantee the improvement of $R_{l}$. Moreover, the structure of $R_{l}$-optimized network is found to be entirely different from that of onion network. In order to design robust networks resistant to more realistic attack condition, we propose a hybrid greedy algorithm which takes both the $R_{n}$ and $R_{l}$ into account. We validate the robustness of our generated networks against malicious attacks mixed with both nodes and links failure. Finally, some economical constraints for swapping the links in real networks are considered and significant improvement in both aspects of robustness are still achieved.