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arXiv · 2407.19871

Fast Private Location-based Information Retrieval Over the Torus

Joon Soo Yoo·Mi Yeon Hong·Ji Won Heo·Kang Hoon Lee·Ji Won Yoon
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Abstract

Location-based services offer immense utility, but also pose significant privacy risks. In response, we propose LocPIR, a novel framework using homomorphic encryption (HE), specifically the TFHE scheme, to preserve user location privacy when retrieving data from public clouds. Our system employs TFHE's expertise in non-polynomial evaluations, crucial for comparison operations. LocPIR showcases minimal client-server interaction, reduced memory overhead, and efficient throughput. Performance tests confirm its computational speed, making it a viable solution for practical scenarios, demonstrated via application to a COVID-19 alert model. Thus, LocPIR effectively addresses privacy concerns in location-based services, enabling secure data sharing from the public cloud.

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Joon Soo Yoo, Mi Yeon Hong, Ji Won Heo, Kang Hoon Lee, Ji Won Yoon. 2024-07-29. Fast Private Location-based Information Retrieval Over the Torus. https://arxiv.org/abs/2407.19871

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