TMSE: A topology modification strategy to enhance the robustness of scale-free wireless sensor networks

Scale-free wireless sensor networks (WSNs) are tolerant to random attacks but vulnerable to malicious attacks. With the increase of cyber-attacks, improving the survivability and robustness is critical to scale-free WSNs. This paper introduces a scale-free topology evolution mechanism (SFTEM) for WSNs, and the evolution model considers the fault probability of nodes as well as the communication range. Then, a new topology modification strategy for enhancing the robustness of scale-free WSNs is presented, namely TMSE. Different from previous works, we consider different types of malicious attack into the algorithm design, making the TMSE more resistant to realistic attacks. Besides, TMSE consists of two operations, in which the high degree operation (HDO) changes the network connections among high degree nodes base on the probability of being attacked, and the degree associativity operation (DAO) transforms the network topology into the onion-like structure using its degree-degree correlation. Meanwhile, all the nodes modified by TMSE maintain the node degree, thus the final topology preserves scale-free properties. Simulation results demonstrate that the network topology generated by SFTEM has the scale-free characteristics, and its robustness can be effectively improved by TMSE, compared to the existing algorithms.