a service providing apparatus provides services in response to requests from a terminal equipment that is coupled thereto via a network . the apparatus includes a first interface part for a first function and used for connection to the terminal equipment , a second interface part for a second function and shared by the terminal equipment and processes of the service providing apparatus , and a shared function providing part interposed between the first and second interface parts for providing shared functions that are used when the terminal equipment that is connected to the service providing apparatus using the first interface part uses the second function .