An authentication device includes a user authentication certificate generation unit that issues to another device user authentication information on which information about a user is recorded; and a right transfer certificate/token generation unit that issues right transfer information and a token corresponding to the right transfer information to another device on the basis of information about a user to whom the right is transferred and a condition under which the right is transferred. A service proxy access device includes a token request unit that requests the issuing of the right transfer information and the token in order to access another device; and a user proxy access unit that accesses another service using the token. The service providing device includes a user authentication certificate request unit that acquires user authentication information from the authentication device using the token.