aiqbench analysis
This research demonstrates a fundamental limitation in quantum cryptography by proving that any protocol secure for the user inherently lacks non-trivial security guarantees for the database owner. The authors provide an explicit attack on cheat-sensitive symmetric private information retrieval, effectively ruling out universal protection against dishonest participants in this specific cryptographic setting. This finding reshapes the theoretical boundaries of what is achievable with current and future quantum protocols for privacy-preserving data access.
Impossibility of Quantum Private Queries
arXiv:2501.12842v5 Announce Type: replace Abstract: Symmetric private information retrieval is a cryptographic task allowing a user to query a database and obtain exactly one entry without revealing to the owner of the database which element was accessed. The task is a variant of general two-party protocols called one-sided secure function evaluation and is closely related to oblivious transfer. Under the name quantum private queries, quantum protocols have been proposed to solve this problem in a cheat-sensitive way: In such protocols, it is not impossible for dishonest participants to cheat, but they risk detection [V. Giovannetti, S. Lloyd, and L. Maccone, Phys. Rev. Lett. 100, 230502 (2008)]. We give an explicit attack against any cheat-sensitive symmetric private information retrieval protocol, showing that any protocol that is secure for the user cannot have non-trivial security guarantees for the owner of the database.
Abstract:Symmetric private information retrieval is a cryptographic task allowing a user to query a database and obtain exactly one entry without revealing to the owner of the database which element was accessed. The task is a variant of general two-party protocols called one-sided secure function evaluation and is closely related to oblivious transfer. Under the name quantum private queries, quantum protocols have been proposed to solve this problem in a cheat-sensitive way: In such protocols, it is not impossible for dishonest participants to cheat, but they risk detection [V. Giovannetti, S. Lloyd, and L. Maccone, Phys. Rev. Lett. 100, 230502 (2008)]. We give an explicit attack against any cheat-sensitive symmetric private information retrieval protocol, showing that any protocol that is secure for the user cannot have non-trivial security guarantees for the owner of the database.
v2,v3,v4: Minor changes. v5: Updated to the journal-published version; scientific content unchanged, with only minor editorial and stylistic changes. Building on the present proof techniques, arXiv:2405.12121 shows lower bounds for quantum secure function evaluation reductions
Quantum Physics (quant-ph); Cryptography and Security (cs.CR)
arXiv:2501.12842 [quant-ph]
(or arXiv:2501.12842v5 [quant-ph] for this version)
Phys. Rev. Research 8, L022036 (2026)
https://doi.org/10.1103/2pd6-j1xf DOI(s) linking to related resources
Full text under the publisher's open licence · 197 words
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