Scale-free networks need not be fragile

We report on computational experiments testing the robustness of scale-free networks. The stylized fact that such networks are robust under random failure but sensitive to targeted attack originates from experiments on instances generated by preferential attachment. We find that these are not representative but rather outliers: they are significantly more fragile under targeted attack than random scale-free networks with the exact same degree sequence. To show that they are, however, not extreme in this respect, we also present two generators producing scale-free networks with the same degree sequence that are even more fragile than the corresponding preferential-attachment networks or more robust than even random graphs. Additionally, we present a new result on Hamiltonian realizability of scaling degree sequences.