Critical nodes identification: A non-cooperative method for unknown topology information in ad hoc networks

The foundation of ad hoc networks lies in the guarantee of continuous connectivity. However, critical nodes, whose failure can easily destroy network connectivity, will influence the ad hoc network connectivity significantly. To protect the network efficiently, critical nodes should be identified accurately and rapidly. Unlike existing critical node identification methods for unknown topology that identify critical nodes according to historical information, this paper develops a critical node identification method to relax the prior topology information condition about critical nodes. Specifically, we first deduce a theorem about the minimum communication range for a node through the number of nodes and deployment ranges, and prove the universality of the theorem in a realistic two-dimensional scenario. After that, we analyze the relationship between communication range and degree value for each node and prove that the greater number of nodes within the communication range of a node, the greater degree value of nodes with high probability. Moreover, we develop a novel strategy to improve the accuracy of critical node identification without topology information. Finally, simulation results indicate the proposed strategy can achieve high accuracy and low redundancy while ensuring low time consumption in the scenarios with unknown topology information in ad hoc networks.