US Patent 7984489 Device registration system and device registration apparatus

When a PC transmits a content request to a device registration apparatus in which a permitted number of devices have already been registered, an expiration time management unit judges whether any registration information registered in a registration list management unit has an exceeded registration expiration time. If registration information with an exceeded registration expiration time is registered in the registration list management unit, the registration list management unit deletes this registration information, and newly registers registration information of the PC.