Abstract
Network robustness and network reliability are important issues in the design of Internet Service Provider's topologies. In this paper, we examine the structural characteristics of network topologies that affect robustness and reliability according to various routing strategies. We examine the interplay between the structural characteristics of network topologies and routing strategies on network robustness and reliability according to resource capacity over-provisioning strategies when the network breakdowns subject to practical constraints (router technology) and economic considerations (link costs). We study the robustness of the Internet connectivity under node intentional harmful attack using two attack strategies: static degree-based and static load-based. We find that the robustness of network topologies is affected by the variation of the interplay between their structural characteristics and the routing strategies. In our proposed approach, we show that highly-heterogeneous topologies have less robustness compared with lightly-heterogeneous topologies. The observations from the robustness study provide us useful insights for proposing multiple efficient preventive resource capacity over-provisioning strategies for mitigation of intentional attacks. The proposed strategies utilize the structural properties by calculating the excess traffic in case of single global cascading failure for each node and measure its influence on the other nodes as well as locally. The results show that our proposed strategies can significantly enhance the robustness and increase the resilience of network topology according to the specific used routing method. Due to our proposed approach results, we also show that highly-heterogeneous topologies have high resilience compared with lightly-heterogeneous topologies.