According to one embodiment, a plurality of output devices includes a communication unit, a storage unit, an intensity transmission unit, a comparison unit, and a control unit. The communication unit communicates with another output device. The storage unit stores an intensity of a host output device. The intensity transmission unit transmits the intensity of the host output device which is stored in the storage unit to the other output device through the communication unit. The comparison unit compares an intensity received from the other output device through the communication unit with the intensity of the host output device which is stored in the storage unit. The control unit controls so as to perform output based on output data when the intensity of the host output device is higher than the intensity received from the other output device as a result of the comparison performed by the comparison unit.

A communication system including an image processing apparatus configured to, in response to receiving acquisition instruction information from a server via indirect communication, receive authentication information from an information processing terminal device via near-field wireless communication, transmit the received authentication information to the server via the indirect communication, and in response to receiving communication instruction information, which indicates a method for data communication with a service providing apparatus, from the server via the indirect communication, perform data communication with the service providing apparatus in accordance with the received communication instruction information.

A management system includes an image forming apparatus and a management server. The management server manages the image forming apparatus. The image forming apparatus is configured to switch a constant connection with the management server by a protocol for the constant connection between enabling and disabling. The management server is configured to operate the image forming apparatus via the constant connection.

An image-forming apparatus includes a controller, a storage, and a communicator. The controller establishes a connection with a terminal device through the communicator by QUIC, stores, in the storage, identification information for identifying the connection and key information to be used for encryption of transmission/reception information transmitted and received to and from the terminal device, performs communication of the transmission/reception information with the terminal device through HTTP/3, and establishes, when the connection with the terminal device is disconnected, a connection with the terminal device using the identification information and the key information so that the communication of the transmission/reception information with the terminal device is resumed.

A communication system including an image processing apparatus configured to, in response to receiving acquisition instruction information from a server via indirect communication, receive authentication information from an information processing terminal device via near-field wireless communication, transmit the received authentication information to the server via the indirect communication, and in response to receiving communication instruction information, which indicates a method for data communication with a service providing apparatus, from the server via the indirect communication, perform data communication with the service providing apparatus in accordance with the received communication instruction information.

A management system includes an image forming apparatus and a management server. The management server manages the image forming apparatus. The image forming apparatus is configured to switch a constant connection with the management server by a protocol for the constant connection between enabling and disabling. The management server is configured to operate the image forming apparatus via the constant connection.

An image-forming apparatus includes a controller, a storage, and a communicator. The controller establishes a connection with a terminal device through the communicator by QUIC, stores, in the storage, identification information for identifying the connection and key information to be used for encryption of transmission/reception information transmitted and received to and from the terminal device, performs communication of the transmission/reception information with the terminal device through HTTP/3, and establishes, when the connection with the terminal device is disconnected, a connection with the terminal device using the identification information and the key information so that the communication of the transmission/reception information with the terminal device is resumed.

An image processing device includes an image processing unit, a UI unit, a VPN processing unit, and a housing. The image processing unit includes a printer and/or a scanner. The UI unit is the target of an input action performed by the user. The VPN processing unit connects to a VPN using authentication information obtained through the UI unit. The image processing unit, the UT unit, and the VPN processing unit are provided to the housing.

An image processing system includes a control apparatus and an image processing apparatus to which the control apparatus is connected and that accesses a network via the control apparatus, wherein remote maintenance by an information processing apparatus is performed via the network. The image processing apparatus connects to a server apparatus that relays communication between the control apparatus and the information processing apparatus. The control apparatus notifies the image processing apparatus that it will restart in accordance with a restart instruction from the information processing apparatus which is connected to the control apparatus via the server apparatus and which maintains the control apparatus remotely, the restart being instructed by the information processing apparatus to the control apparatus while the remote maintenance of the control apparatus is continuing, and instructs the image processing apparatus to reconnect to the server apparatus, in accordance with completion of the restart of the control apparatus.

An image processing device includes an image processing unit, a UI unit, a VPN processing unit, and a housing. The image processing unit includes a printer and/or a scanner. The UI unit is the target of an input action performed by the user. The VPN processing unit connects to a VPN using authentication information obtained through the UI unit. The image processing unit, the UT unit, and the VPN processing unit are provided to the housing.