System comprising a server for providing a service to an image forming apparatus, and authentication thereof

A communication system configured to perform data communication with a service providing apparatus on an Internet, the communication system comprising:

• an image processing apparatus:
• a server on the Internet;
• and
• an information processing terminal device comprising:
• a terminal-side storage;
• a first network interface;
• a user interface;
• and
• a first controller configured to:
• accept, via the user interface, an input of an instruction to perform a preparation process to connect the image processing apparatus with the service providing apparatus;
• in response to accepting the input of the instruction to perform the preparation process via the user interface, transmit transmission request information via the first network interface, the transmission request information being for requesting transmission of authentication information, the authentication information representing authorization to perform data communication with the service providing apparatus;
• receive the authentication information via the first network interface;
• store the received authentication information into the terminal-side storage;
• and
• transmit the authentication information stored in the terminal-side storage, to the image processing apparatus via the first network interface,
• wherein the image processing apparatus comprises:
• an image processor;
• a second network interface;
• an operation interface;
• and
• a second controller configured to:
• accept, via the operation interface, an input of an instruction to perform data communication with the service providing apparatus;
• in response to accepting the input of the instruction to perform data communication with the service providing apparatus, transmit communication request information to the server via the second network interface, the communication request information being for requesting the server to perform data communication with the service providing apparatus;
• receive acquisition instruction information from the server via the second network interface, the acquisition instruction information being for instructing the image processing apparatus to receive the authentication information;
• receive the authentication information from the information processing terminal device via the second network interface;
• transmit the received authentication information to the server via the second network interface;
• and
• perform data communication with the service providing apparatus via the second network interface, and
• wherein the server comprises:
• a third network interface configured to communicate with an external device via the Internet;
• and
• a third controller configured to:
• in response to receiving the communication request information from the image processing apparatus via the third network interface, transmit the acquisition instruction information to the image processing apparatus via the third network interface.