Cascading failures of social networks under attacks

Although cascading failures have occurred on many real-world networks, to our best knowledge, no one has clearly identified this issue on a social network. In this paper, we identify this potential issue on social networks, and develop a theoretical model to analyze related issues. Note that highly-influential “super” users play critical roles on a social network. When they are suddenly unavailable, a large portion of the social network may be seriously disrupted. The proposed model captures this dynamic process and helps us better understand related issues. Furthermore, we evaluate the proposed model under four attack strategies based on real social network datasets collected on Twitter and Sina Weibo. We also analyze the connectivity, the persistent time, and the cascade effect of a social network under these attacks. Our results show that social network service providers have to pay closer attention to super users to avoid dramatic failures.