Abstract: The robustness of real networks to deliberate attacks has always been an important issue in network science. By considering the actual Internet, the power function of node degree is used to define the initial load of nodes, and the cascading model under local load redistribution is constructed. The effects of two different attack strategies on network robustness are compared, and the influence of important network parameters on network robustness under intentional attack is studied. Through the numerical simulation experiment, the following conclusions are drawn: 1) When the initial load parameter is greater than a certain threshold, attacking high load nodes does harm to the network more than attacking low load nodes， but when the initial load parameter is less than the threshold, attacking low load nodes can destroy the network more effectively； 2) The smaller the initial load parameter, the larger the capacity parameter of a node, the stronger the robustness of the network. The research results of this paper can provide reference for the control and defense of cascading failures on the Internet.

Key words: cascading failures, Internet, threshold, intentional attacks