摘要:
A network device is provided. The network device includes a communicating unit, which is adapted to communicate with an information processing device via a network to make an operational setting for encrypted communication to be established between the network device and the information processing device, a searching packet receiving unit to receive a searching packet to search for network devices transmitted from the information processing device, a judging unit to judge status of the operational setting for the encrypted communication, a reply packet generating unit to generate a reply packet including information regarding the result of the judgment made by the judging unit in response to the searching packet which is received by the searching packet receiving unit, and a reply packet transmitting unit to transmits the reply packet generated by the reply packet generating unit to the information processing device via the network.
摘要:
Technology is provided, which allows to easily find tampering of event logs created by an information processing device and transmitted to a log management apparatus, without increasing communication load. A printer (i.e. information processing device) creates a hash value from the event log of an event every time the event occurs. The printer generates a digital signature by encrypting the hash value with its own private key. The printer transmits the signature-bound event log obtained by binding the digital signature with the event log to a server (i.e. log management apparatus). The server decrypts the hash value from the event log of the received signature-bound log information using a device public key. The server also generates a new hash value from the event log. The server verifies the coincidence of the decrypted hash value and the new hash value, and authenticates signature-bound event logs for which this coincidence has been verified. The server stores signature-bound event logs that have been authenticated. Every time an event occurs, the printer transmits an event log bound with a digital signature that is created using its private key. Only signature-bound event logs are communicated between the printer and the server. Event log tampering can easily be discovered from the signature-bound event logs. Thus, tampering of event logs can easily be discovered without increasing the communication load between the printer and server.
摘要:
A communication system including a communication control device connecting to an external network, a NAT device connecting to the external network, and a terminal device connecting to an internal network under control of the NAT device, the terminal device including a NAT information identification portion, a NAT information transmitting portion that transmits NAT type information to the communication control device, a type request transmitting portion, a type response receiving portion that receives the NAT type information transmitted from the communication control device in response to the type request signal, and a first communication portion that performs communication with another terminal device using the received NAT type information, the communication control device including a NAT information receiving portion, a storage control portion that stores the received NAT type information in a storage device, a type request receiving portion, and a type response transmitting portion that transmits the stored NAT type information.
摘要:
A second terminal device is used in a system including a connection management server, a first terminal device, and the second terminal device. The second terminal device includes: a local address obtaining unit configured to obtain a first local IP address and first authentication information of the first terminal device from the connection management server, if a first global IP address matches a second global IP address; a determination unit configured to determine, by using of the obtained first authentication information, whether a first particular terminal device with which the second terminal device can communicate by use of the first local IP address is the first terminal device; and a target data communication unit configured to communicate first data with the first terminal device by using the first local IP address, if the first particular terminal device is determined to be the first terminal device.
摘要:
A network device, connectable with a service providing server and an authentication sever via a network, includes an acquisition information storage storing acquisition information for acquiring a certificate corresponding to each of services the service providing server provides, a certificate storage storing certificates acquired from the authentication server, a determining unit that, in response to acceptance of a request for utilizing a service, determines whether a certificate necessary for utilizing the requested service is stored in the certificate storage, and a controller that, when the necessary certificate is not stored, reads out acquisition information for the necessary certificate from the acquisition information storage, makes a certificate acquiring unit acquire the necessary certificate from the authentication server using the acquisition information, and stores the necessary certificate into the certificate storage. When the necessary certificate is stored, the controller makes the certificate acquiring unit acquire the necessary certificate from the certificate storage.
摘要:
A system includes a communication control device, a first communication device and a second communication device. The communication control device acquires first network information that identifies a first internal network to which the first communication device is connected, and second network information that identifies a second internal network. The communication control device decides a first method based on the acquired information. The first method indicates a method of transmission from the first communication device to the second communication device, and of transmission from the second communication device to the first communication device. The communication control device transmits information indicating the first method to the first communication device and the second communication device. The first communication device and the second communication device mutually communicate using the first method, based on the received information indicating the first method.
摘要:
A communication device performs P2P communication with the other communication device by establishing a session through a server, and includes a first transmitting portion, if the communication device operates as a called device requested to establish the session, upon the receiving a session start message from the other communication device, transmits to the other communication device a response message including information on a port for directly receiving data from the other communication device; a session establishing portion establishes the session by transmitting a control message to a port specified by information in the session start message or a response message received from the other communication device; a command accepting portion accepts a user's command permitting to receive from the other communication device; and a starting portion starts transmitting and receiving of data to and from the other communication device, upon the accepting of the command.
摘要:
A communication system includes a first communication terminal, a second communication terminal that has not established communication with the first communication terminal, and a third communication terminal that has established communication with the first communication terminal. The second communication terminal transmits to the first communication terminal a request packet that requests establishment of communication, and receives from the first communication terminal a permission packet that permits establishment of communication. The second communication terminal then establishes communication with the first communication terminal and performs communication with the first communication terminal. A second receiving device receives the request packet from the third communication terminal, after the first receiving device has received the permission packet from the first communication terminal; The second communication terminal transmits the permission packet to the third communication terminal, and establishes communication with the third communication terminal and performs communication with the third communication terminal.
摘要:
The first telephone server may be configured so as to be capable of communicating with a second telephone server with which a first wireless telephone device is registered. The first telephone server may be configured to receive authentication information sent from the first wireless telephone device located within a wireless communication area of the first telephone server. The first telephone server may be configured to send a first command including the authentication information to the second telephone server. The first telephone server may be configured to receive a first response sent in response to the first command from the second telephone server. The first telephone server may be configured to receive a call request, sent from the first wireless telephone device to a second wireless telephone device, by using a wireless communication. The first telephone server may be configured to send the call request to the second wireless telephone device by using the wireless communication without utilizing the second telephone server on a condition that the first response is a positive response and the second wireless telephone device is located within the wireless communication area. The first telephone server may be configured to receive, by means of wireless communication, a second response sent in response to the first command from the second wireless telephone device. The first telephone server may be configured to send the second response to the first wireless telephone device by using the wireless communication.
摘要:
A printing system has a printer and a terminal device. The printer has a first data receiving unit to receive print data and layout data request that requests the terminal device to transmit layout data representing an arrangement of objects, a layout data generating unit to generate the layout data based on the print data, and a second data transmitting unit to transmit the layout data to the terminal device. The terminal device has a first data transmitting unit to transmit the print data and the layout data request to the printer, a second data receiving unit to receive the layout data from the printer, a preview image generating unit to generate preview image data representing a printing result with the use of the layout data, and a display unit to display a preview image represented by the preview image data on a display unit.