| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To reduce the amount of communication of data to be exchanged in oblivious keyword search between an information provider and a user, and to verify whether information providing is performed properly by following the procedure. <P>SOLUTION: By applying a system based on discrete logarithm problem on an elliptic curve whose key length size can be set to 160 bit or so, the amount of communication is reduced to one-third in comparison with the conventional RSA signature system. Also, by applying Weil pairing or Tate pairing defined on the elliptic curve for illegality prevention for the information provider, it can be verified whether the information providing is performed properly by following the procedure. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
