Sillcom: A Communication-Efficient Privacy-Preserving Scheme for Indoor Localization

This paper presents Sillcom, a high-performance secure indoor localization scheme designed to minimize both communication and computational costs while preserving participants’ privacy. Unlike existing privacy-preserving indoor localization techniques, which suffer from high computational overhead and excessive communication, Sillcom integrates replicated secret sharing and function secret sharing in an outsourcing model to achieve significantly lower online communication overhead. A multi-branch tree structure and multi-thread parallelism further optimize both the offline and online phases. Experimental results demonstrate that Silcom outperforms the state-of-the-art online-efficient scheme FAPRIL, reducing online communication by a factor of 15 and end-to-end query time by 75%.