{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,21]],"date-time":"2026-05-21T21:32:25Z","timestamp":1779399145116,"version":"3.53.1"},"reference-count":41,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2025,2,21]],"date-time":"2025-02-21T00:00:00Z","timestamp":1740096000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Key R&amp;D Program","award":["2020YFA0712303"],"award-info":[{"award-number":["2020YFA0712303"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cryptography"],"abstract":"<jats:p>Private information retrieval (PIR) enables a client to retrieve a specific element from a server\u2019s database without disclosing the index that was queried. This work introduces three improvements to the efficient single-server PIR protocol Spiral. We found that performing a modulus switching towards expanded ciphertexts can improve the server throughput. Secondly, we apply two techniques called the composite NTT algorithm and approximate decomposition to Spiral to further improve it. We conduct comprehensive experiments to evaluate the concrete performance of our protocol, and the results confirm an approximately 1.7 times faster overall throughput than Spiral.<\/jats:p>","DOI":"10.3390\/cryptography9010013","type":"journal-article","created":{"date-parts":[[2025,2,21]],"date-time":"2025-02-21T06:39:07Z","timestamp":1740119947000},"page":"13","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Faster Spiral: Low-Communication, High-Rate Private Information Retrieval"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0009-0003-1098-1519","authenticated-orcid":false,"given":"Ming","family":"Luo","sequence":"first","affiliation":[{"name":"Key Laboratory of Cyberspace Security Defense, Institute of Information Engineering, School of Cyber Security, University of Chinese Academy of Sciences, Beijing 100085, China"},{"name":"School of Cyber Security, University of Chinese Academy of Sciences, Beijing 101408, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mingsheng","family":"Wang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Cyberspace Security Defense, Institute of Information Engineering, School of Cyber Security, University of Chinese Academy of Sciences, Beijing 100085, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,2,21]]},"reference":[{"key":"ref_1","unstructured":"Chor, B., Goldreich, O., Kushilevitz, E., and Sudan, M. 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