| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To solve the problem in a conventional service providing system wherein high cost is needed for a device for generating a group key. <P>SOLUTION: This service providing system using a group signature system comprises a group key seller device 10 which generates a group key; a service agent device 20 which issues use permission information to a member who uses a predetermined service by use of the group key generated by the group key seller device 10 and determines validity of the member who uses the predetermined service; a user device 40 which generates group signature data based on the use permission information to receive provision of the predetermined service; and a service providing agent device 30 which requests to confirm validity of the member based on the group signature data to the service agent device 20, and provides the predetermined service to the member based on the answer result of the confirmation request. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
