The spreading of dangerous malware in inter-dependent networks of electronics devices has raised deep concern, because from the ICT networks infections may propagate to other Critical Infrastructures producing the well-known domino effect. Researchers are attempting to develop a high level analysis of malware propagation, discarding software details, in order to generalize to the maximum extent the defensive strategies. It has been suggested that the maximum eigenvalue could act as a threshold for the malware's spreading. In this paper we study the Italian Internet Autonomous System simulating the diffusion of a worm, verifying the theoretical threshold and showing how to choose in a sub-optimal way the set of most influential nodes to protect with respect to the spectral paradigm. Our algorithm is fast and outperforms measures as degree, closeness, betweenness, and dynamical importance. © 2013 Springer-Verlag.

cited By 0; Conference of 6th International Workshop on Critical Information Infrastructures Security, CRITIS 2011 ; Conference Date: 8 September 2011 Through 9 September 2011; Conference Code:100143