Comment on “flexible protocol for quantum private query based on B92 protocol”
In a recent paper (Quantum Inf Process 13:805–813, 2014), a flexible quantum private query (QPQ) protocol based on B92 protocol is presented. Here we point out that the B92-based QPQ protocol is insecure in database security when the channel has loss, that is, the user (Alice) will know more records in Bob’s database compared with she has bought.
KeywordsQuantum private query Database security Non-orthogonal projection measurement
This work is supported by NSFC (Grant Nos. 61402058, 61572086), the Fund for Middle and Young Academic Leaders of CUIT (Grant No. J201511), the Science and Technology Support Project of Sichuan Province of China (Grant No. 2013GZX0137), the Fund for Young Persons Project of Sichuan Province of China (Grant No. 12ZB017) and the Foundation of Cyberspace Security Key Laboratory of Sichuan Higher Education Institutions (Grant No. szjj2014-074).
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