Abstract: A localization system includes an animal transceiver and a floor transceiver circuit. The animal transceiver is configured to be fixed to an animal to transceive a radio frequency signal. The floor transceiver circuit is arranged on a floor surface and configured to determine a position of the animal transceiver within the floor surface on the basis of the radio frequency signal received from the animal transceiver. An animal cage includes a cage configured to accommodate an animal, and the localization system.

Abstract: A system for measuring the attenuation of electromagnetic shielding of an infrastructure as a function of the frequency, including a transmitter of a white noise signal with a constant power over a frequency band between a minimum frequency and a maximum frequency, a signal receiver, the transmitter and the receiver being capable of sending a signal and receiving a signal across the infrastructure, the receiver including a filter module capable of applying sliding filter on the received signal between the minimum frequency and the maximum frequency, and a double synchronous detection module capable of double synchronous detection on a signal output by the filter module.

Abstract: A method, apparatus and user terminal for measuring with a discovery signal are disclosed in the present document. The method includes: when measuring reference signal receiving quality (RSRQ) based on a discovery signal, performing a received signal strength indication (RSSI) measurement in a sub-frame where a discovery signal is located and/or a sub-frame without the discovery signal; and acquiring the RSRQ according to the measured RSSI. With the present document, the RSSI measurement is performed based on the sub-frame where the discovery signal is located and/or the sub-frame without the discovery signal, which can reduce the measurement deviation caused by the situation that there is no data in a data channel after a cell is closed, and increase the RSRQ measurement accuracy.

Abstract: A method for locating a terrestrial transmitting source of an unknown signal that is transmitted via satellite to a terrestrial receiver, wherein the method includes comparing a power fluctuation of the unknown signal with a power fluctuation of at least one known signal allocated to a terrestrial transmitting source and determining a degree of similarity between the power fluctuation of the unknown signal and the power fluctuation of the at least one known signal.

Abstract: A vehicle message broadcasting method includes determining whether a transmission power set for broadcasting a message by a communication device using a first wireless communication scheme is to be adjusted, the first wireless communication scheme being used to transmit a safety message (SM), broadcasting a safety message (SM) using the first wireless communication scheme with a transmission power based on a result of the determining, broadcasting at least one additional message including information included in the SM and/or information related to the SM using a second wireless communication scheme having a wider coverage than a coverage of the first wireless communication scheme.

Abstract: There are provided a terminal apparatus, a base station apparatus, and a communication system capable of reporting efficient reception quality information when the reception quality information is transmitted in the communication system having a terminal apparatus having different reception functions. The terminal apparatus includes: a reception unit that receives information related to a network assisted interference cancellation and removal function, a channel state information request, and information related to a channel state information reporting configuration; and a transmission unit that transmits a channel state information report feedback including a predetermined number of channel state information values in accordance with the information related to the channel state information reporting configuration and the channel state information request.

Abstract: A method and apparatus for multiplexing reference signals in a predetermined number of Code Division Multiplexing (CDM) groups to balance power across Orthogonal Frequency Division Multiplexing (OFDM) symbols are disclosed. In a wireless communication system, orthogonal sequences used for spreading the reference signals are allocated such that the order of orthogonal sequences allocated to a subcarrier of one CDM group has a predetermined offset with respect to the order of orthogonal sequences allocated to a subcarrier of another CDM group, adjacent to the subcarrier of the one CDM group.

Abstract: A satellite communications system can use a spread-spectrum waveform and format, a synchronization scheme, and/or a power management algorithm. This approach can provide benefits such as allowing every terminal to communicate with every other terminal, link margin permitting. This gives the network a mesh topology although it can be configured in a star topology for highly asymmetric applications. A further understanding of the nature and the advantages of particular embodiments disclosed herein may be realized by reference of the remaining portions of the specification and the attached drawings.

Abstract: To provide an optical communication device, an optical communication system, an optical communication method, and a program with which the confidentiality of information included in an optical signal can be ensured even when the optical signal is transmitted to a device which is not the original transmission destination device. An optical communication device equipped with: a reception unit that receives a wavelength-multiplexed optical signal; a demultiplexing unit that demultiplexes the wavelength-multiplexed optical signal into first demultiplexed light that includes a first wavelength and second demultiplexed light that includes a second wavelength; a processing unit capable of performing a prescribed process on a signal possessed by the first demultiplexed light; and a multiplexing unit that multiplexes the first demultiplexed light on which the prescribed process had been performed and the second demultiplexed light, and then outputs the resulting multiplexed light.

Abstract: A data transmission control method, passive optical network (PON) equipment and apparatus, and a PON are presented. The method includes obtaining, by first PON equipment, data transmission information between the first PON equipment and second PON equipment; determining a target line rate between the first PON equipment and the second PON equipment according to the data transmission information; and transmitting data on a line between the first PON equipment and the second PON equipment according to the target line rate. The equipment includes an obtaining unit, a determining unit, and a communications unit. In the embodiments of the present disclosure, energy consumption of an optical network unit (ONU) can be reduced when service traffic of the ONU is light.

Abstract: A system and method that enforces one or more policy rules on user-allocated bandwidth portions of the overall system bandwidth, for example in an optical fiber transmission system. The policy rules may limit, for example, the range of optical wavelengths, the acceptable range on the output-power-spectral density and/or the total per-band optical power within the user-allocated bandwidth that a user may provide on the system. The system may include one or more user control units that receives respective user output signals and applies all policy rules. The resulting optical output(s) of the UCU(s) may be provided an optical transmission path for transmission to a receiving terminal. In the receiving terminal, one or more UCU(s) may apply receiver policy rules, for instance by limiting the range of wavelengths transmitted to a receive subsystem.

Abstract: This disclosure describes methods, apparatus, and systems related to a modulation and coding scheme (MCS) system. The device may determine a wireless communications channel with a first device in accordance with a wireless communications standard. The device may generate a header in accordance with a communication standard, the header including, at least in part, a modulation and coding scheme (MCS) index value. The device may determine a code rate associated with the MCS index value based at least in part on the wireless communications channel. The device may cause to send the header to the first device over the wireless communications channel based at least in part on the MCS index value.

Abstract: The invention relates to a method for periodic transmission of real time data in a computer system, particularly a distributed computer system, which computer system is comprised of node computers (201-208), particularly an appreciable number of node computers (201-208), and distributor units (211-215), particularly an appreciable number of distributor units (211-215), wherein the node computers (201-208) and the distributor units (211-215) have access to a global time, and wherein real time data are transmitted by means of time-triggered real time messages, wherein selected distributor units (212, 213, 214, 215) form a central structure of distributor units; and wherein during a periodic communication round (PCR), in the error-free case, at least two copies of each real time message to be sent are transmitted via at least two independent routes through the central structure, by executing a satisfying or an optimal time plan, from a start distributor unit in the central structure to a target distributor un

Abstract: Disclosed are a broadcast signal transmitter, a broadcast signal receiver, and a method for transceiving a broadcast signal in the broadcast signal transmitter/receiver. A method for transmitting a broadcast signal comprises the following steps: signaling in-band signaling information to at least one of a service component physical layer pipe (PLP) including at least one service component of a broadcast service, a first information PLP including first service information applied to one broadcast service and a second information PLP including second service information applied commonly to a variety of broadcast services; performing the FEC encoding on data included in each PLP; performing time-interleaving on the FEC encoded data; generating a transmission frame including the time-interleaved data; and modulating the transmission frame and transmitting a broadcast signal including the modulated transmission frame.

Abstract: Embodiments of the present invention provide a decoding method and apparatus. The method includes: receiving K user signals by using N subcarriers, where one user signal is carried on at least two subcarriers of the N subcarriers, one subcarrier carries at least two user signals of the K user signals, and 2?N<K; determining, from the N subcarriers, at least two target subcarriers that carry a target user signal, and performing initialization calculation on the target subcarriers, to obtain initialization calculation results; and determining, in a logarithm domain, a probability of each codeword in a codebook of the target user signal according to the initialization calculation results, to decode the target user signal. According to this method, decoding can be performed in the logarithm domain with low complexity.

Abstract: A method for detecting a format of data in a wireless local area network and a device using the same are provided. The device receives a physical layer protocol data unit (PPDU) that includes a first field and a second field. The device determines a first format of the PPDU based on at least one of the first field and the second field and determines a second format of the PPDU based on a modulation phase of the PPDU.

Abstract: A receiver, transmitter and method for enabling a replay using a packetized link protocol are provided. In one embodiment, the method includes: (1) transmitting a stream of packets including an untagged packet and (2) using synchronized counters to determine a sequence ID of the untagged packet, which is a corrupt/lost packet that needs to be retransmitted.

Abstract: A method in a wireless network node for handling the configuration of bundle sizes in communications involving the transmission and/or reception of more than one bundle in a transmission and/or reception attempt, comprises the step of initiating the use of a first bundle size for communicating with a wireless device during an initial transmission and/or an initial reception, the first bundle size comprising a first number of repetitions. The method comprises initiating the use of at least a second bundle size for communicating with the wireless device during at least one retransmission and/or subsequent reception associated, respectively, with the initial transmission and/or initial reception, wherein the at least second bundle size comprises a smaller number of repetitions compared to the first bundle size.

Abstract: Provided is a terminal device with which deterioration in hybrid automatic repeat request (HARQ) retransmission performance can be inhibited by continuing a downlink (DL) HARQ process for DL data before and after changing the uplink link-DL configuration. In this device, a decoder stores, in a retransmission buffer, DL data transmitted from a base station, and decodes the DL data, and a wireless transmitter transmits a response signal generated using a DL-data-error detection result. A soft buffer is partitioned into a plurality of regions for each retransmission process on the basis of the highest values among retransmission process numbers respectively stated in a plurality of configuration patterns which can be set in the terminal.

Abstract: Longer pilot sequences can be supported by transmitting pilot values of a given pilot sequence over different orthogonal frequency division multiplexed (OFDM) symbols of an uplink frame. The pilot values may be contiguous, or non-contiguous, with one another in the time domain. Consecutive pilot values in a pilot sequence may be transmitted in different OFDM symbols of the frame. For example, odd pilot values (e.g., P1, P3, P5 . . . ) in a pilot sequence may be transmitted over a different OFDM symbol than even pilot values (e.g., P2, P4, P6 . . . ) in the pilot sequence. Alternatively, a leading subset of pilot values in a pilot sequence is transmitted over a different OFDM symbol than a trailing subset of pilot values in the pilot sequence.

Abstract: Provides are a method and an apparatus for transmitting a feedback frame in a wireless local area network (WLAN) system. Specifically, a station (STA) receives, from an access point (AP), a null data packet announcement (NDPA) frame indicating transmission of a null data packet (NDP). The STA receives the NDP from the AP. The STA transmits, to the AP, a feedback frame including channel state information determined based on the NDP. The channel state information indicates a feedback subcarrier in each subcarrier group. The subcarrier group is generated based on grouping information using subcarriers in a frequency band excluding a guard subcarrier and a DC subcarrier. The feedback subcarrier is included in a subcarrier with an odd-numbered subcarrier index. The feedback subcarrier corresponds to a subcarrier with an even-numbered subcarrier index that is adjacent to the subcarrier with the odd-numbered subcarrier when the subcarrier with the odd-numbered subcarrier is a null subcarrier.

Abstract: A millimeter radio wave communication system. In a method for operating a base station (BS) in an analog/digital mixed BF system, an analog BF direction is determined. A digital BF precoder is determined for the determined analog BF direction. Digital BF precoding is performed using the digital BF precoder with respect to the determined analog BF direction. A DownLink Reference Signal (DL RS) is transmitted in the analog BF direction on which the digital BF precoding has been performed.

Abstract: In embodiments, apparatuses, methods, and storage media may be described for distinguishing, by a user equipment (UE), a reference signal (RS) transmitted by a cell that may have a same identifier (ID) as another cell in a network. In embodiments, a muting pattern, a time offset, or a virtual cell identifier (VCID) may be used to generate an RS sequence or RS resource allocation.

Abstract: Methods and apparatus for enabling interference coordination in a communication network. A base station includes a plurality of antenna ports. Each antenna port is configured to transmit a reference signal, and each antenna port is associated with a respective cell. The base station determines a set of cells where transmissions of reference signals is to be performed from a reduced set of the plurality of antenna ports. The base station determines a subset of antenna ports in at least one cell of the determined set of cells to enable interference coordination in the network, and transmits the reference signal from the subset of antenna ports.

Abstract: Methods and apparatus are disclosed for enabling a narrowband MTC device to operate in a legacy LTE system having a wider system bandwidth. The physical downlink control channel for a narrow-band MTC device, also referred to as low-complexity physical downlink control channel (LC-PDCCH), has reduced bandwidth resource and can support no more than 6 physical resource blocks. The present application discloses how to allocate physical resource blocks (PRBs) for LC-PDCCH and physical downlink shared channel (PDSCH). The PRB allocation methods disclosed herein allow the MTC devices to derive the frequency location of the PDSCH PRBs from the frequency location of the LC-PDCCH PRBs and to soft-combine LC-PDCCH transmissions and PDSCH transmissions for performance improvement.

Abstract: A virtual gateway software application may comprise a graphical user interface, and be configured to receive immediate command instructions for local connected devices from each of: a user, via the graphical user interface; a remote server on the Internet; and a physical network bridge of at least one of the connected devices via a wireless LAN or a short-range communication protocol. The application may relay the immediate command instructions to one or more of the connected devices via the wireless LAN or the short-range communication protocol while the device on which the application resides is within the particular building environment. It may store delayed command instructions for the local connected devices from each of: the user, via the graphical user interface; and the remote server on the Internet; and relay one or more of the delayed command instructions from the mobile communication device to one or more of the connected devices via the wireless LAN or the short-range protocol.

Abstract: Embodiments of a transmission signaling structure for HEW are defined to carry packet information to configure OFDMA receivers for demodulation of a specific portion of the packet and/or to configure receivers for transmission using specific OFDMA and MU-MIMO resources. In some embodiments, the specific portion of the packet comprises one or more minimum bandwidth units of one or more 20 MHz channels. Each 20 MHz bandwidth structure may comprise several minimum bandwidth units to allow each 20 MHz channel to have a have smaller granularity than 20 MHz.

Abstract: Embodiments of the present invention relate to the field of communications technologies, and provide an interference cancellation apparatus and method, which can avoid being limited by a dynamic range of an ADC/DAC and can cancel a second-type self-interference component effectively. The interference cancellation apparatus includes a main receive antenna, a divider, a first-type interference canceller, a down converter, a filter, a coupler, a digital down-conversion unit, a second-type interference reconstructor, and a local-frequency signal generator. The present invention is used for interference cancellation.

Abstract: The present disclosure discloses a method and device for transmitting ACK/NACK indication information. A network-side device configures at least two carriers for a UE; transmits PDCCH information to the UE; selects one of at least two timing relationships as a first timing relationship; determines a corresponding third uplink subframe and first carrier; indicate related information corresponding to the third uplink subframe and the first carrier to the UE; in the third uplink subframe of the first carrier, determines a first channel resource, and indicates the first channel resource to the UE; and receives an ACK/NACK fed back by the UE on the allocated resource.

Abstract: A self-promoting mesh network node is described that renders manual designation of new mesh network nodes unnecessary. When joining a new mesh network, the self-promoting mesh network node broadcasts a series of up to three different types of signals and scans for a mesh network address received in response thereto. Upon receipt of a mesh network address, the self-promoting mesh network node adopts the address and sends a join message to the mesh network router or node that provided the address. Once part of a mesh network, the self-promoting mesh network node will send a promotion permission request to the mesh network router if it receives a coordinator promotion request from a new node attempting to join the network.

Abstract: A configurable sensor trap is described that comprises a plurality of translation modules stored in a memory, each of which is dynamically associable with one or more of a plurality of pins of a processor. The translation modules allow the configurable sensor trap to be quickly configured to translate sensor data from any of a variety of incoming signal formats into a desired output signal format before the data is transmitted to the cloud.

Abstract: The present invention relates to a method and an apparatus for receiving, in a wireless communication system supporting carrier aggregation and usage change of a radio resource, a signal of a terminal which does not support simultaneous reception and transmission of aggregated cells. Specifically, the method comprises the steps of: receiving downlink control information for a secondary cell on a specific radio resource corresponding to a special subframe of a primary cell and a downlink subframe of the secondary cell; and determining validity of the downlink control information according to an uplink-downlink setting of the primary cell, wherein the downlink control information is determined to be invalid if the primary cell is in non-fallback mode, and determined to be valid if the primary cell is a time division duplex (TDD) uplink-downlink setting according to fallback mode and the secondary cell is cross-carrier scheduled according to the primary cell.

Abstract: Methods, systems, and devices for wireless communication are described. A wireless device may identify an uplink/downlink (UL/DL) configuration that defines subframe configuration options for each subframe of a frame. For example, the UL/DL configuration may establish parameters for time division duplexing (TDD) operation between a base station and a user equipment (UE). The wireless device (e.g., the UE or base station) may determine a constraint for a subframe of the frame based on the UL/DL configuration and then determine an adaptive subframe configuration based on the constraint. The adaptive subframe configuration may include one or several downlink symbol periods and one or several uplink symbol periods.

Abstract: A technology is described for increasing signal booster while maintaining network protections. A distance from the signal booster to one or more base stations can be estimated. A base station coupling loss (BSCL) value can be calculated based on the estimated distance. A gain and/or a noise power of an uplink signal of the frequency band can be adjusted based on the BSCL value while maintaining network protections.

Abstract: Techniques for duplex communication and power transfer across an isolator are provided. In an example, a first transceiver coupled to a firs-t side of an isolator can include a transmit modulator configured to receive first data and timing signals, to provide control signals to oscillate an output of the transceiver to transmit power and to order each half-cycle of an oscillation cycle of the output to transmit the first data. A second transceiver coupled to a second side of the isolator can include a receive detection circuit configured to compare a received oscillation cycle with a plurality of thresholds and to provide a plurality of comparator outputs indicative of reception of the positive half-cycle and the negative half-cycle, and a receive decoder configured to identify the order of half-cycles and to provide an output indicative of logic level of the first data.

Abstract: A method for transmitting uplink control information by a user equipment (UE) in a wireless communication system using time division duplex (TDD), the UE being configured with a first component carrier (CC) and a second CC having different uplink-downlink configurations, the method comprising: determining hybrid automatic repeat request acknowledgement (HARQ-ACK) information for the first CC based on min (M1, W); determining HARQ-ACK information for the second CC based on min (M2, W); and transmitting bit information corresponding to the HARQ-ACK information for the first and second CCs through a physical uplink shared channel (PUSCH) in an uplink subframe, wherein min (A, B) represents a smallest number from A and B, W represents an uplink downlink assignment index (UL DAI) value indicated by an uplink grant for the PUSCH, M1 represents a number of downlink subframes corresponding to the uplink subframe on the first CC, and M2 represents a number of downlink subframes corresponding to the uplink subframe on

Abstract: Embodiments of a dual-mode radio system are disclosed. In one embodiment, the radio system includes a first radio unit including a transmitter, a receiver, an antenna, and switching circuitry adapted to couple either an output of the transmitter of the first radio unit or an input of the receiver of the first radio unit to the antenna of the first radio unit. In addition, the radio system includes a second radio unit including an antenna and either a transmitter having an output coupled to the antenna of the second radio unit, a receiver having an input coupled to the antenna of the second radio unit, or both a transmitter having an output selectively coupled to the antenna of the second radio unit and a receiver having an input selectively coupled to the antenna of the second radio unit. The radio system has both a full-duplex mode and a half-duplex mode.

Abstract: A computing apparatus outputs ?1 and ?2 corresponding to a ciphertext x, a capability providing apparatus uses ?1 to correctly compute f(?1) with a probability greater than a certain probability and sets the result of the computation as z1, uses ?2 to correctly compute f(?2) with a probability greater than a certain probability and sets the result of the computation as z2, the computing apparatus generates a computation result u=f(x)bx1 from z1, generates a computation result v=f(x)ax2 from z2, and outputs ub?va? if the computation results u and v satisfy a particular relation, where G and H are groups, f(x) is a function for obtaining an element of the group G for x?H, X1 and X2 are random variables having values in the group G, x1 is a realization of the random variable X1, and x2 is a realization of the random variable X2.

Abstract: Embodiments of the invention disclose a data transmitting method, a server and a client.

Abstract: The invention prevents intercepted keys from being used in unauthorized whitebox descrambler modules for the decryption of a ciphertext. Hereto a receiver with a personalized whitebox descrambler is proposed, whereby a part of the descrambling operation of the personalized descrambler is performed in a preprocessing module external to the descrambler.

Abstract: Embodiments of the present invention disclose a method, system, and computer program product for bluesalt security. A computer receives a confidential data configuration wherein specific sensor are assigned to specific confidential information. The assigned sensors are measured for values as a system administrator enters a password corresponding to the confidential information. The measured values are converted into a salt and concatenated with the password to generate a primary key. The primary key is used to encrypt the confidential information, then the primary key is encrypted using a secondary key comprised of a second password with a second set of sensor information as the salt. The encrypted key is saved securely while the secondary key is destroyed. In order to decrypt the confidential information, a user must replicate the password and sensor values to generate the primary or secondary key.

Abstract: Embodiments of the present invention disclose a method, system, and computer program product for bluesalt security. A computer receives a confidential data configuration wherein specific sensor are assigned to specific confidential information. The assigned sensors are measured for values as a system administrator enters a password corresponding to the confidential information. The measured values are converted into a salt and concatenated with the password to generate a primary key. The primary key is used to encrypt the confidential information, then the primary key is encrypted using a secondary key comprised of a second password with a second set of sensor information as the salt. The encrypted key is saved securely while the secondary key is destroyed. In order to decrypt the confidential information, a user must replicate the password and sensor values to generate the primary or secondary key.

Abstract: A system, apparatus, method, and machine readable medium are described for authentication with asymmetric cryptography. For example, a method in accordance with one embodiment comprises: generating a challenge at a server; encrypting the challenge at the server using a public encryption key; transmitting the encrypted challenge to a connected device having a first connection over a network with the server; providing the encrypted challenge from the connected device to a user device; decrypting the encrypted challenge using a private encryption key corresponding to the public encryption key to determine the challenge; converting the challenge to a converted challenge, the converted challenge having a different format than the original challenge; receiving the converted challenge at the connected device and providing the converted challenge from the connected device to the server; and validating the converted challenge at the server to authenticate the user.

Abstract: In accordance with embodiments of the present disclosure, an information handling system may include a processor, an information handling resource communicatively coupled to the processor, and a management controller communicatively coupled to the processor and the information handling resource and configured to provide out-of-band management of the information handling system. The management controller may further configured to receive a message indicating that an existing private key associated with the information handling resource is compromised, the message including a replacement public key for replacing an existing public key associated with the information handling resource and associated with the existing private key and responsive to the message, cause the existing public key associated with the information handling resource to be replaced with the replacement public key.

Abstract: The present invention concerns a method for encrypted data synchronization, wherein the method comprises providing at least one data entity (100) comprising data content (110), accompanying metadata (120) including an entity key (140) usable for encrypting the data content (110), and synchronization metadata (130) usable for synchronizing the at least one data entity (100) between at least two first devices (400), wherein at least the entity key (140) of the accompanying metadata (120) and the synchronization metadata (130) are encrypted using a second key.

Abstract: A wireless communications device is constituted from a control station and a slave station that perform encryption communication using an encryption key and changes the encryption key in a predetermined procedure, during a call, and the device includes a controller that operates in such a manner that audio is reduced, if the procedure in which the encryption key is changed is not correctly executed, in a case where a change of the encryption key is made.

Abstract: A first device may receive a toll-free data request that includes an application signature. The toll-free data request may request that a first entity be billed for data usage by a second device associated with a second entity, and may be received from an application. The first device may decrypt the application signature to obtain a device identifier and an application identifier. The first device may validate the application signature based on the device identifier and the application identifier. The first device may selectively cause the first entity or the second entity to be billed for data usage associated with the toll-free data request based on a result of validating the application signature.

Abstract: Systems and methods for managing digital identities. In some embodiments, a method is provided, comprising acts of: using a plurality of measurements taken from a user to generate an identifier for the user, the identifier comprising a cryptographic proof of the plurality of measurements; instantiating a digital identity representation associated with the identifier for the user, the digital identity representation comprising program code that implements rules for attestation; generating an electronic signature over the digital identity representation; and publishing the digital identity representation and the electronic signature to a distributed ledger system.

Abstract: The present invention generally relates to one or more line replacement units (“LRUs”) for an airplane. The LRUs can include airline modifiable information (“AMI”) that includes more than one public key certificates, wherein each of the more than one public key certificates uniquely identifies the airplane for ground communication based, at least in part, on a public key or a private key associated with the one or more public/private key pairs generated by a cryptographic key generator.

Abstract: Provided is a vehicle system constituted by a master ECU and a general ECU. The general ECU attaches a digital signature to transmission data including the data (for example, a digest value of a program) and transmits the transmission data to the master ECU. The master ECU verifies the digital signature and the data and, when both the digital signature and the data are valid, determines that the general ECU is valid. The master ECU attaches a digital signature to transmission data including the data of the master ECU and a session key and transmits the transmission data to the general ECU. The general ECU verifies the digital signature and the data and, when both the digital signature and the data are valid, the general ECU uses the session key included in the transmission data as a common key when performing subsequent communications.