Patent ID: 8196190

Claim:
An authentication server that performs user account maintenance and user authentication, the authentication server comprising: a storage unit configured to store a user authentication table in which user account information is registered; a processor; and a memory configured to store at least one program executable by the processor, the at least one program comprising program code that, when executed by the processor, implements: a save unit configured to, in response to a request for user authentication, save information of a device that requests the user authentication in an authentication requesters list in association with account information of a user that requested the user authentication; and a deletion unit configured to, in response to a user account information deletion request, delete account information of a user targeted for deletion from the user authentication table and issue a deletion request to delete information related to the user targeted for deletion to a device whose information is saved in the authentication requesters list in association with the account information of the user targeted for deletion.