Analysis of Range-Free Anchor-Free Localization in a WSN under Wormhole Attack

Localization is a fundamental problem in wireless sensor networks. Currently, most localization protocols assume a benign environment. This paper studies how a localization protocol can be affected by attacks, especially those like wormhole attacks that don't need to capture the keys used in the network, and how Such an attack can be detected and defended in distributed scheme,. By applying several localization algorithms, this paper first shows that, wormhole attacks are a serious threat to all these algorithms, based oil simulation in NS-2. The paper first evaluates the, effects of wormhole attacks oil several Range-Free Anchor-Free (RFAF) localization algorithms based on hop-counting and connectivity techniques. Then, the paper presents an RFAF localization algorithm called Wormhole-resilient Geographic Distributed Localization (WGDL), which embeds a wormhole detecting/recovering mechanism: if this mechanism detects wormhole attacks in location computation, then it will restore the localization by freezing the wormhole affected area. Simulations show that the proposed detection method is effective oil different, network placements, and that the mechanism has both a low False Toleration Rate (FTR) and a low False Detection Rate (FDR) in detecting wormhole attacks.