Research On The Robustness Of Complex Networks Based On Different Deliberate Attack Strategies

Many infrastructures can be abstracted into complex networks,which would be completely paralyzed since a series of "domino" cascading failures when one of functional components of infrastructure network viciously damaged.Therefore,the robustness of infrastructure networks is rather important.In this study,the effects of cascading failures caused by several different deliberate attack strategy on the robustness of infrastructure networks were investigated.The main research contents are described as follows:In the past,the nodes with high degree of centrality index are preferentially attacked;however,the influence of nodes marked with low degree of centrality index in topology structure in the network is usually ignored.Although the number of such nodes is relatively small,the whole network would be fragmented when these nodes are attacked.In order to precise understanding the impact of failure of this kind of special nodes on whole network,collect impact(CI)attack strategy has been proposed.In which,a sphere of radius r is built around each node in the network,and the sum of the effects of all nodes set on the boundaries of the spheres on the central node is calculated.The central node with the highest sum of effects is selected as attacked node in three systems,including common facility networks,typical scale-free networks and random networks,respectively.The simulation results showed that compared with the degree attack strategy,betweenness attack strategy and K-Shell attack strategy,the three actual facility networks and scale-free networks are more prone to cascading failure when attacked by CI attack strategy.Furthermore,it is found that these attack strategies have the same effect on the cascading failure of random network.The internal topology of complex network would be changed after attacking,resulting in the corresponding variation of node degree value and other indicators in the network.To analyse the influence of changes of internal network topology on robustness of infrastructure networks,a dynamic model has been utilized.In this model,the degree index value of remaining nodes in the network would be re-calculated before each attacking.The variations of degree index,neighbor nodes contact ratio index,half local centricity index,local characteristic index and index were simulated and recorded.Besides,the influence of different deliberately objects on the network robustness also has been studied.The simulation results showed that compared with common attack modes,different deliberate attack algorithms in dynamic attack mode have better attack effects.Beijing metro network,Hangzhou metro network,IEEE57 power network and BA scale-free network are less robustuess to the above six attack strategies than WS small world network and North American aviation network.In addition,The attack algorithm based on the coincidence degree of neighbor nodes is easier to cause the cascading failure of the network.