Information-Theoretic Authenticated PIR: From PIR-RV To APIR

Computer Science > Cryptography and Security [Submitted on 24 Apr 2026] Information-Theoretic Authenticated PIR: From PIR-RV To APIR Pengzhen Ke, Yuxuan Qin, Liang Feng Zhang Private Information Retrieval (PIR) allows clients to retrieve database entries without leaking retrieval indices, yet malicious servers seriously compromise retrieval correctness. Existing Authenticated PIR (APIR) schemes resist selective-failure attacks but rely on computational hardness assumptions. In contrast, information-theoretic PIR with Result Verification (itPIR-RV) achieves integrity without computational assumptions, yet only provides relaxed query privacy with no defense against selective-failure attacks. This paper focuses on unconditionally secure information-theoretic APIR (itAPIR) constructions. We propose the rigorous information-theoretic security definition for itAPIR with statistical privacy against selective-failure attacks and integrity as core properties, formalize the hierarchical relation between itAPIR and itPIR-RV as a relaxed variant with identical integrity but basic query privacy, and prove a conversion theorem that valid itPIR-RV schemes can be directly upgraded to secure itAPIR with no extra overhead. Our work bridges the theoretical gap, simplifies itAPIR design, and enables quantum-resistant PIR in malicious server environments. Comments: 6 pages, 1 table, accepted by ISIT 2026 Subjects: Cryptography and Security (cs.CR) Cite as: arXiv:2604.22505 [cs.CR]   (or arXiv:2604.22505v1 [cs.CR] for this version)   https://doi.org/10.48550/arXiv.2604.22505 Focus to learn more Submission history From: Pengzhen Ke [view email] [v1] Fri, 24 Apr 2026 12:33:20 UTC (84 KB) Access Paper: HTML (experimental) view license Current browse context: cs.CR < prev   |   next > new | recent | 2026-04 Change to browse by: cs References & Citations NASA ADS Google Scholar Semantic Scholar Export BibTeX Citation Bookmark Bibliographic Tools Bibliographic and Citation Tools Bibliographic Explorer Toggle Bibliographic Explorer (What is the Explorer?) Connected Papers Toggle Connected Papers (What is Connected Papers?) Litmaps Toggle Litmaps (What is Litmaps?) scite.ai Toggle scite Smart Citations (What are Smart Citations?) Code, Data, Media Demos Related Papers About arXivLabs Which authors of this paper are endorsers? | Disable MathJax (What is MathJax?)