| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To enable to precisely specify a user of an ID after update even when an encryption key is updated at generation of ID by encryption processing. <P>SOLUTION: An update information generation device receives a connection request to a service offer server from a user terminal, generates service use identification information using present encryption key, and transmits it to the service offer server. When the service offer server does not maintain received service use identification information, the service offer server notifies to the update information generation device that the server does not maintain the service use identification information. When the update information generation device receives the notice, the device generates service use identification information using an encryption key whose generation is older than the generation of present encryption key, transmits the information to the service offer server in order; and when the service offer server maintains the received service use identification information, the device updates the coincided service use identification information to the service use identification information generated by present encryption key. <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
