KGPT: Wireless Key Generation Based on Power Tuning for Static Internet-of-Things

Wireless key generation is an emerging key sharing solution for Internet-of-Things (IoT) devices, which heavily relies on wireless signal fluctuations. However, most IoT devices have remained static ever since being deployed, where their stable wireless signals seriously deteriorate the effectiveness of key generation. In this article, we proposea new wireless Key Generation approach based on Power Tuning (KGPT) for statice IoT. Unlike the existing methods, KGPT does not require any additional helpers or any hardware modifications, thus, suiting practical static IoT deployments. We analyze the possibility of eavesdropping on the existing wireless key generation. We propose three power tuning strategies to generate wireless signal fluctuations for key generation in static IoT while defending against eavesdropping. In a static IoT scenario, we conduct experimental evaluations to first verify the eavesdropping on multi-antenna wireless key generation and then demonstrate the effectiveness of the proposed KGPT in producing sufficient signal fluctuations for key generation. Results show that KGPT can achieve a correlation value up to 0.97 for legitimate links while resisting the correlation of eavesdropping links down below 0.4.