Instability of scale-free networks under node-breaking avalanches, Europhys

PACS. 89.75.Fb – Structures and organization in complex systems. Abstract. – The instability introduced in a large scale-free network by the triggering of node-breaking avalanches is analyzed using the fiber-bundle model as conceptual framework. We found, by measuring the size of the giant component, the avalanche size distribution and other quantities, the existence of an abrupt transition. This test of strength for complex networks like Internet is more stringent than others recently considered like the random removal of nodes, analyzed within the framework of percolation theory. Finally, we discuss the possible implications of our results and their relevance in forecasting cascading failures in scale-free networks. The recent months have witnessed a great effort devoted to the unraveling of the proper-ties of complex networks [1, 2]. These properties include the rules followed in the process of formation of the net, the resulting connectivity distribution of the networks and their robust-ness under unfavorable circumstances like the presence of acting damaging agents, etc. [3–5]. This general interest is mainly due to the fact that the subject of complex networks has a considerable impact on many branches of science and technology and also in sociology [6–11]