Abstract: A control device is a control device in a control system in which the control device connected via a network to a server in which an appliance and a user's smartphone assigned to control the appliance are stored in association with each other receives an instruction from the user's smartphone and controls an operating condition of an appliance. The control device determines whether a signal received from a different terminal satisfies a predetermined criterion. If the control device determines that the signal satisfies the predetermined criterion, the control device cuts off all communications via the network.

Abstract: An HEMS controller receives a certificate revocation list distributed from a certificate authority server and listing serial numbers of revoked electronic certificates. The serial number of the electronic certificate includes a first identifying part that indicates a value for identifying a type of a participation node maintaining the electronic certificate and a second identifying part that indicates a value for identifying an individual participation node. In the case the certificate revocation list includes a serial number in which the second identifying part is a predetermined value, the HEMS controller determines that the electronic certificate of a participation node that meets the type indicated by the first identifying part of the serial number is invalid.

Abstract: A first controller generates a first group key, executes first mutual authentication with devices within a group, and shares the first group key with the devices that have succeeded in first mutual authentication. When a second controller joins the group, the first controller decides a coordinator that manages a group key used in common in the group. The first controller executes second mutual authentication with the coordinator, and shares the first group key with the coordinator when the second mutual authentication is successful. The coordinator performs encrypted communication within the group using the first group key, generates a second group key when valid time of the first group key is equal to or smaller than a predetermined value, executes third mutual authentication with the devices and a third controller, and updates the first group key of the devices and the third controller that have succeeded in the third authentication.

Abstract: An authentication method for a group of devices connected to a network includes selecting the first controller as a coordinator, the coordinator being configured to manage a group key to be used in common in the group. The method includes generating the group key, and performing first mutual authentication and second mutual authentication. The method also includes sharing the group key with each device for which the first mutual authentication has been successful, and sharing the group key with each second controller for which the second mutual authentication has been successful. The method further includes encrypting transmission data by using the group key to generate encrypted data, generating, authentication data by using the group key, and simultaneously broadcasting a message to each device for which the first mutual authentication has been successful and each second controller for which the second mutual authentication has been successful.

Abstract: A first controller generates a first group key, executes first mutual authentication with devices within a group, and shares a first group key with devices that have succeeded in authentication. At least one controller within the group decides a coordinator that manages a group key used in common in the group, from controllers including a second controller newly joined in the group. The first controller executes second mutual authentication with the coordinator, and shares the first group key with the coordinator. The coordinator performs encrypted communication within the group using the first group key. The coordinator generates a second group key when valid time of the first group key is equal to or smaller than a predetermined value, executes third mutual authentication with the devices and controllers within the group, and updates the group key of the devices and controllers that have succeeded in authentication to the second group key.

Abstract: At least one controller in a group selects a coordinator that manages a group key to be used in common in the group from among controllers in the group in accordance with an attribute of the controllers. The selected coordinator generates a group key, performs mutual authentication with devices and the controllers in the group, and shares the generated group key with devices and controllers that have been successfully authenticated. The coordinator then generates encrypted data and authentication data by using the group key and simultaneously broadcasts a message including the encrypted data and the authentication data.

Abstract: A first device according to one embodiment includes, but is not limited to, receiver circuitry, determinator circuitry, and transmitter circuitry. The receiver circuitry is configured and/or programmed to receive from a second device, first information for controlling a third device. The determinator circuitry is configured and/or programmed to determine whether or not the first information is to be transmitted to the third device, based on whether or not the first information is associated with second information stored in the first device. The second information includes at least a first operation command for controlling a first operation of the third device. The transmitter circuitry is configured and/or programmed to, in a case that the first information is determined to be transmitted to the third device, transmit the first information to the third device.

Abstract: A new controller (supporting device authentication) is a controller which performs encrypted communication with a device which has succeeded in mutual authentication using an electronic certificate, and the controller includes: a determining unit that determines whether or not a communication target device with which communication is to be performed is an authentication support device that supports the mutual authentication; a functional restriction unit that, when the communication target device is determined not to be the authentication support device by the determining unit, imposes a functional restriction on one or more functions of the communication target device which are operable by the new controller (supporting device authentication); and a communication unit which performs communication in plain text with the communication target device with the functional restriction imposed by the functional restriction unit.

Abstract: A first device according to one embodiment includes, but is not limited to, receiver circuitry, determinator circuitry, and transmitter circuitry. The receiver circuitry is configured and/or programmed to receive from a second device, first information for controlling a third device. The determinator circuitry is configured and/or programmed to determine whether or not the first information is to be transmitted to the third device, based on whether or not the first information is associated with second information stored in the first device. The second information includes at least a first operation command for controlling a first operation of the third device. The transmitter circuitry is configured and/or programmed to, in a case that the first information is determined to be transmitted to the third device, transmit the first information to the third device.

Abstract: A first device according to one embodiment includes, but is not limited to, receiver circuitry, determinator circuitry, and transmitter circuitry. The receiver circuitry is configured and/or programmed to receive from a second device, first information for controlling a third device. The determinator circuitry is configured and/or programmed to determine whether or not the first information is to be transmitted to the third device, based on the first information received and second information stored in the first device. The second information regards at least a first parameter of the third device that the second device is authorized to control. The transmitter circuitry is configured and/or programmed to, in a case that the first information is determined to be transmitted to the third device, transmit the first information to the third device.

Abstract: In a communication system including: a control apparatus which controls pairing for communication according to kinds of pairing methods; and devices each of which performs pairing for communication according to one or more predetermined kinds of pairing methods, and performs encryption communication with the control apparatus by pairing with the control apparatus, wherein the control apparatus includes: a kind obtaining unit which obtains, from each device, the predetermined kinds of pairing methods for the device; a combination determining unit which determines, for each device, a combination of a same kind of pairing methods included in both the plurality of kinds of pairing methods for the control apparatus and the predetermined kinds of pairing methods obtained by the kind obtaining unit; and a display unit which displays, to a user, the combination of the same kind of pairing methods determined by the combination determining unit according to a predetermined condition.

Abstract: A communication device according to the present invention aims to restart data transmission/reception between communication devices in a short amount of time, without performing key sharing again, even when a communication device of a transmitting side is rebooted. The communication device includes a volatile memory storing a count value, a generator generating data including a count value, a communicator transmitting data to another communication device, a storage instructor, each time the communicator transmits data, updating the volatile memory with a count value, and a nonvolatile memory. A count value is incremented each time the communicator transmits data, the storage instructor causes the nonvolatile memory to store a count value at certain intervals, and the generator, when the communication device is rebooted, includes in data a sum of a certain value and a count value stored in the nonvolatile memory.

Abstract: A communication system, including: a NW management device which (i) forms a network together with an authenticated target device, and (ii) manages the network by delivering a session key for use in communication in the network to the authenticated target device; and a device authenticated by the NW management device, wherein the NW management device: determines whether or not to permit the device to be an alternative management device which manages the network in replace of the NW management device when communication is impossible in the network; shares, with the device, authentication information about the authenticated target device, when permitting the device to be the alternative management device; and the device shares the authentication information with the NW management device, and starts managing the network using the authentication information as the alternative management device when determining that the NW management device cannot communicate in the network.

Abstract: At least one controller in a group selects a coordinator that manages a group key to be used in common in the group from among controllers in the group in accordance with an attribute of the controllers. The selected coordinator generates a group key, performs mutual authentication with devices and the controllers in the group, and shares the generated group key with devices and controllers that have been successfully authenticated. The coordinator then generates encrypted data and authentication data by using the group key and simultaneously broadcasts a message including the encrypted data and the authentication data.

Abstract: A wireless communication device has an aim of specifying, when transmitting data to another communication device, an antenna among antennas that can transmit data at a low transmission power. The wireless communication device switches between a first antenna and a second antenna upon transmission of a request signal to the other communication device, and increases or decreases transmission power for transmitting the request signal when switching between the first antenna and the second antenna.

Abstract: In a communication system including: a control apparatus which controls pairing for communication according kinds of pairing methods; and devices each of which performs pairing for communication according to one or more predetermined kinds of pairing methods, and performs encryption communication with the control apparatus by pairing with the control apparatus, wherein the control apparatus includes: a kind obtaining unit which obtains, from each device, the predetermined kinds of pairing methods for the device; a combination determining unit which determines, for each device, a combination of a same kind of pairing methods included in both the plurality of kinds of pairing methods for the control apparatus and the predetermined kinds of pairing methods obtained by the kind obtaining unit; and a display unit which displays, to a user, the combination of the same kind of pairing methods determined by the combination determining unit according to a predetermined condition.

Abstract: A first controller generates a first group key, executes first mutual authentication with devices within a group, and shares a first group key with devices that have succeeded in authentication. At least one controller within the group decides a coordinator that manages a group key used in common in the group, from controllers including one or more controllers and a second controller newly joined in the group, in accordance with attributes of the controllers. The first controller executes second mutual authentication with the coordinator, and shares the first group key with the coordinator in a case where the authentication is successful. The coordinator performs encrypted communication within the group using the first group key.

Abstract: A wireless communication device has an aim of specifying, when transmitting data to another communication device, an antenna among antennas that can transmit data at a low transmission power. The wireless communication device switches between a first antenna and a second antenna upon transmission of a request signal to the other communication device, and increases or decreases transmission power for transmitting the request signal when switching between the first antenna and the second antenna.

Abstract: A communication device according to the present invention aims to restart data transmission/reception between communication devices in a short amount of time, without performing key sharing again, even when a communication device of a transmitting side is rebooted. The communication device includes a volatile memory storing a count value, a generator generating data including a count value, a communicator transmitting data to another communication device, a storage instructor, each time the communicator transmits data, updating the volatile memory with a count value, and a nonvolatile memory. A count value is incremented each time the communicator transmits data, the storage instructor causes the nonvolatile memory to store a count value at certain intervals, and the generator, when the communication device is rebooted, includes in data a sum of a certain value and a count value stored in the nonvolatile memory.

Abstract: In a power line communication system, a control device sets an intra-breaker communication period during which communication is performed between communication terminals connected to a single breaker, and an inter-breaker communication priority period during which communication is performed between communication terminals connected to different breakers from each other. The control device operates filters so that the filters allow signals that travel via breakers to pass through the filters during the inter-breaker communication priority period, and so that the filters block signals that travel via breakers from passing through the filters during the intra-breaker communication period.