To provide a system for providing content or an application capable of restricting a terminal device in which the content or the application is able to be used to a single terminal device among one authorized terminal device and one or more unauthorized terminal devices. According to a generation rule, a new authentication symbol string is generated based on at least a part of an authentication symbol string stored in a first authentication symbol string storage unit (100). In a case where the new authentication symbol string belongs to a type of an authentication symbol string that is able to be generated, according to the above mentioned generation rule, based on at least a part of an authentication symbol string stored in a second authentication symbol string storage unit (200) so as to be correlated to terminal identification information, use of content or an application in a terminal device (10) is permitted, and the authentication symbol string stored in the first authentication symbol string storage unit (100) and the authentication symbol string stored in the second authentication symbol string storage unit (200) so as to be correlated to the terminal identification information are updated to the above mentioned new authentication symbol string.