Abstract: An authentication system having a user apparatus that performs authentication using first authentication data and a second authentication server that performs authentication using second authentication data is provided. The user apparatus acquires the second authentication data from a user and requests authentication of the user by sending the acquired second authentication data to the second authentication server. The second authentication server performs authentication of the user on a basis of the second authentication data received from the user apparatus and sends the user apparatus a result of the authentication and when the authentication is successful, first authentication data stored being associated with the user. The user apparatus acquires a result of authentication based on the first authentication data received from the second authentication server and performs login processing when the acquired result of the authentication based on the first authentication data indicates success.

Abstract: To identify a storage medium storing an electronic file, as a location of the electronic file, and to detect a location move of a file stemming from a replacement of a storage medium, a file management system 100 includes a log acquisition unit 110: detecting an event having occurred on a file stored in a storage medium; checking, with a table, pieces of information of logical paths of locations of the file before and after the event; identifying pieces of medium identification information of storage media in which the file is located before and after the event are identified; and then storing the pieces of medium identification information in a terminal log database as location information of the file.

Abstract: Recipient machine sends a contents request message with recipient's public key to entitlement granter machine. On the entitlement granter machine, digital rights data relevant to the contents request is encrypted with the recipient's public key. Encrypted digital rights data with the entitlement granter's digital signature thereon is returned to recipient machine. On the recipient machine, encrypted digital rights data is decrypted with the recipient's secret key. The recipient machine sends a message containing digital rights data thus decrypted, recipient's public key, and the above encrypted data to contents distributor machine.