Paper 2025/210
Practical Keyword Private Information Retrieval from Key-to-Index Mappings
Abstract
This paper introduces practical schemes for keyword Private Information Retrieval (keyword PIR), enabling private queries on public databases using keywords. Unlike standard index-based PIR, keyword PIR presents greater challenges, since the query's position within the database is unknown and the domain of keywords is vast. Our key insight is to construct an efficient and compact key-to-index mapping, thereby reducing the keyword PIR problem to standard PIR. To achieve this, we propose three constructions incorporating several new techniques. The high-level approach involves (1) encoding the server's key-value database into an indexable database with a key-to-index mapping and (2) invoking standard PIR on the encoded database to retrieve specific positions based on the mapping. We conduct comprehensive experiments, with results showing substantial improvements over the state-of-the-art keyword PIR, ChalametPIR (CCS'24), i.e., a
Metadata
- Available format(s)
-
PDF
- Category
- Cryptographic protocols
- Publication info
- Published elsewhere. Minor revision. USENIX Security 2025
- Keywords
- keyword PIR
- Contact author(s)
-
menghao303 @ gmail com
weiran lwr @ alibaba-inc com
plq270998 @ alibaba-inc com
zhangcong @ mail tsinghua edu cn
pfwu @ smu edu sg
zongchao zl @ taobao com
hongweili @ uestc edu cn
robertdeng @ smu edu sg - History
- 2025-02-12: approved
- 2025-02-12: received
- See all versions
- Short URL
- https://ia.cr/2025/210
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2025/210, author = {Meng Hao and Weiran Liu and Liqiang Peng and Cong Zhang and Pengfei Wu and Lei Zhang and Hongwei Li and Robert H. Deng}, title = {Practical Keyword Private Information Retrieval from Key-to-Index Mappings}, howpublished = {Cryptology {ePrint} Archive, Paper 2025/210}, year = {2025}, url = {https://eprint.iacr.org/2025/210} }