ANONYMOUS SEARCH SYSTEM, ANONYMOUS SEARCH METHOD, AND ANONYMOUS SEARCH PROGRAM

摘要

A management device (500) stores an encryption tag (C(D)) and encrypted data in association with each other. Upon acquiring a search keyword (s) for searching for encrypted data stored in the management device (500) a search device (400) calculates unambiguously determined deterministic information (t) from the search keyword (s) and generates a search query (Q(s)) by executing probabilistic encryption on the search keyword (s) using the deterministic information (t). The search device (400) transmits the search query (Q(s)) to the management device (500). After receiving the search query (Q(s)) from the search device (400) the management device (500) determines whether the search keyword (s) obtained by decrypting the search query (Q(s)) matches a relevant keyword obtained by decrypting the encryption tag (c) stored in the management device (500).