SERVICE PROVIDING SYSTEM, OUTSOURCING BUSINESS DEVICE, SERVICE PROVIDING METHOD, AND PROGRAM

摘要

A client is enabled to receive member services, at the time of asking an outsourcing business for the services, while keeping the member information secret from the outsourcing business, and without any communication with the user. At the time of using the services, a user device (3) transmits group signature data to an outsourcing business device (2). The outsourcing business device (2) verifies the group signature data by using the public information of a client device (1). When the verification is satisfied to confirm that the user device (3) is a member of the client device (1), the outsourcing business device (2) provides services for the user device (3). ® KIPO & WIPO 2008