BLIND SECRET KEY ISSUING SYSTEM, BLIND DATA RETRIEVAL SYSTEM, METHOD OF THE SAME, KEY GENERATING SERVER, DECRYPTION DEVICE AND PROGRAM

摘要

PROBLEM TO BE SOLVED: To provide a blind secret key issuing technique and a blind data retrieval technique to which privacy safety is added.;SOLUTION: A decryption device 4 of a blind inner product encryption system includes: a first calculation part which calculates (αg,βg,(αv_1,ig)_i=1,...,n,(βv_2,ig)_i=1,...,n,(v_3,ig)_i=1,...,n) and transmits it to a decryption device; a zero knowledge certification device which performs 5-round zero knowledge certification to a key generating server 2; and a second calculation part which calculates sk_v→:=α^-1k₁^*+β^-1k₂^*+k₃^*=(1,δγv^→,0²ⁿ,η^→,0)_B* to make sk_v→ become a secret key to a secret predicate vector v^→. The key generating server includes the first calculation part which calculates k₁^*,k₂^*,k₃^* and transmits it to the decryption device.;SELECTED DRAWING: Figure 1;COPYRIGHT: (C)2016,JPO&INPIT