Increasing base-station anonymity in wireless sensor networks

Nodes in a wireless sensor network (WSN) probe their surroundings and report their findings to a base-station over multi-hop paths. Given the important role of the base-station, an adversary who likes to disrupt the network operation would eagerly look for where the base-station could be and target it with attacks in order to inflict maximum damage. Unfortunately, the continuous flow of traffic towards the base-station creates a pronounced pattern of wireless links that may expose the base-station position and thus make the network more vulnerable.This paper investigates means for boosting the anonymity of the base-station. First, we adapt three models – entropy based model, GSAT test and evidence theory model, to quantify anonymity of the base-station. Then, two novel approaches for boosting the anonymity of the base-station are proposed. One is for the base-station to disguise itself by transmitting some of the data packets it receives with varying intensity. The goal is to create a perception that the base-station node is just another sensor node sending some information and thus confuse the adversary. The second approach is for the base-station to relocate itself to a more concealed position within the network. Relocating the base-station completely scraps/nullifies the adversary’s efforts to track it down and forces him to start his search from scratch. This paper investigates the problem of base-station relocation with respect to when to relocate, where to relocate and how to relocate. These approaches are validated through simulation. Our results show that the proposed measures not only safeguard base-station but also increases the lifetime of the WSN due to uniform energy depletion of sensor nodes.