JP4788204B2 - Cryptographic communication system and breaker device - Google Patents

Description

  The present invention relates to an encryption communication system in which a plurality of communication terminal devices are communicably connected to each other using an encrypted communication signal via a conductor line shared for power supply voltage supply and communication. And it is related with the encryption key setting method utilized for such an encryption communication system, a communication terminal device, and a breaker apparatus.

  Power lines are installed in various places such as dwellings and office buildings to supply power. In recent years, power line carrier communication using this power line as a transmission line is being established. In this power line carrier communication, since communication between devices is realized using an existing power line, devices can be networked without newly introducing and constructing a dedicated communication line. For example, a communication system is known that performs power line carrier communication using a control terminal such as a wall switch to turn on and off (close / open) a load terminal such as a lighting fixture or an air conditioner (see, for example, Patent Document 1). .)

In such a communication system, a power line is used as a communication path, and since the power line is connected to another dwelling unit or office beyond the user's dwelling unit or office, a communication signal transmitted or received by the communication system used by the user. Is transmitted to another dwelling unit or office via the power line, and there is a high possibility that information is leaked to the outside. Therefore, information leakage is prevented by encrypting the communication signal.
JP 2004-208472 A

  By the way, when the communication signal is encrypted as described above, it is necessary to distribute and set the encryption key used for encryption and decryption of the communication signal in advance to each communication terminal device. However, when the encryption key is distributed by communication, the encryption key is also distributed to the next house or another office via the power line, which causes a disadvantage that information leakage occurs. Also, if the encryption key is distributed by broadcasting, the distribution destination of the encryption key cannot be limited to a specific communication terminal device. For example, the encryption key is set only for the communication terminal device in a specific room in the house. There was an inconvenience that there was no degree of freedom.

  The present invention has been made in view of such problems, and is an encryption communication system, an encryption key setting method, a communication terminal device, and a breaker that can easily set an encryption key only to a desired communication terminal device. An object is to provide an apparatus.

The cryptographic communication system according to the present invention is a cryptographic communication in which a plurality of communication terminal devices are communicably connected to each other using an encrypted communication signal via a conductor line shared for power supply voltage supply and communication. a system, wherein the plurality of communication terminals, the encryption keys used: a communication unit that performs communication with another communication terminal through the conductor wire, to encrypt and decrypt the previous SL communication signal A distribution instruction receiving unit for receiving a distribution instruction for instructing distribution, and when a distribution instruction for instructing distribution of the encryption key is received by the distribution instruction receiving unit, the communication unit transmits the encryption key to another communication terminal. and encryption key distribution process section for transmitting to the device, before SL and setting instruction receiving section for receiving a setting instruction to set the encryption key, preset predetermined after the encryption key has been received by the communication unit If the setting indicated by the setting instruction receiving section in Chi hours is accepted, an encryption key setting unit that sets an encryption key that is the received as an encryption key for the encryption and compounding of the communication signal, the When the setting instruction is received by the setting instruction receiving unit within a predetermined time after the encryption key is received by the communication unit, the fact that the encryption key has been received is notified. A reception notification unit that does not perform the notification when the setting instruction is not received by the setting instruction reception unit within the predetermined time after the encryption key is received by the communication unit; and the setting instruction reception unit A confirmation instruction accepting unit for accepting a confirmation instruction for instructing confirmation of the setting instruction accepted by the encryption key setting unit by the reception notification unit. When the confirmation instruction is received by the confirmation instruction receiving unit within the waiting time after the notification that the reception has been performed, the received encryption key is encrypted with the communication signal. If the confirmation instruction is not received by the confirmation instruction receiving unit within the waiting time, the encryption key is set. Do not do .

Also, in the cryptographic communication system according to the present invention, a plurality of communication terminal devices are communicably connected to each other using an encrypted communication signal via a conductor line shared for supply of power supply voltage and communication. a cryptographic communication system, wherein the plurality of communication terminal devices, used a communication unit for performing communication with another communication terminal through the conductor wire, to encrypt and decrypt the previous SL communication signal A distribution instruction receiving unit that receives a distribution instruction for instructing distribution of an encryption key; and when the distribution instruction for instructing distribution of the encryption key is received by the distribution instruction receiving unit, and encryption key distribution process section for transmitting to the communication terminal device, before SL and setting instruction receiving section for receiving a setting instruction to set the encryption key, the encryption key is preset after being received by the communication unit If the setting instruction is accepted by the setting instruction receiving section within a constant latency, and encryption key setting unit that sets an encryption key that is the received as an encryption key for the encryption and compounding of the communication signal The plurality of communication terminal devices include an operation reception unit that receives an operation instruction, and the operation reception unit receives the operation instruction when the communication unit receives the operation instruction without receiving the encryption key. When the operation instruction is received within a predetermined waiting time after the encryption key is received, the operation instruction is used as the setting instruction. It functions as the setting instruction receiving unit that receives .

Also, in the cryptographic communication system according to the present invention, a plurality of communication terminal devices are communicably connected to each other using an encrypted communication signal via a conductor line shared for supply of power supply voltage and communication. a cryptographic communication system, the plurality of communication terminal devices, e Bei a communication unit that performs communication with another communication terminal through the conductor lines, one communication among the plurality of communication terminals The terminal device includes at least a distribution instruction receiving unit that receives a distribution instruction that instructs distribution of an encryption key used for encryption and decryption of the communication signal, and a distribution that instructs distribution of the encryption key by the distribution instruction receiving unit. If the instruction is accepted, and a the encryption key distribution processing unit to transmit to another communication terminal device by an encryption key the communication unit, the other communication terminal device, at least, set the encryption key When the setting instruction is received by the setting instruction receiving unit within a predetermined waiting time after the encryption key is received by the communication unit, and a setting instruction receiving unit that receives a setting instruction that instructs An encryption key setting unit that sets the received encryption key as an encryption key for encryption and decryption of the communication signal, and the setting instruction receiving unit detects the presence or absence of a power supply voltage on the conductor wire. When the power supply voltage is not detected within a predetermined waiting time set in advance after the encryption key is received, the setting instruction is accepted .

Also, in the cryptographic communication system according to the present invention, a plurality of communication terminal devices are communicably connected to each other using an encrypted communication signal via a conductor line shared for supply of power supply voltage and communication. In the cryptographic communication system, the plurality of communication terminal devices include a communication unit that performs communication with another communication terminal device via the conductor wire, and at least one communication among the plurality of communication terminal devices. The terminal device has a distribution instruction receiving unit that receives a distribution instruction for instructing distribution of an encryption key used for encryption and decryption of the communication signal, and a distribution instruction for instructing distribution of the encryption key by the distribution instruction receiving unit. An encryption key distribution processing unit that, when accepted, causes the communication unit to transmit the encryption key to another communication terminal device, and other communication terminal devices other than the one communication terminal device include the encryption key A setting instruction accepting unit for accepting a setting instruction for instructing the setting; and the setting instruction accepting unit accepts the setting instruction within a predetermined waiting time after the encryption key is received by the communication unit. An encryption key setting unit configured to set the received encryption key as an encryption key for encryption and decryption of the communication signal, and the setting instruction receiving unit includes a power supply voltage on the conductor wire. When the power supply voltage is not detected within a predetermined waiting time set after the encryption key is received, the setting instruction is accepted.

Also, in the cryptographic communication system according to the present invention, a plurality of communication terminal devices are communicably connected to each other using an encrypted communication signal via a conductor line shared for supply of power supply voltage and communication. An encryption communication system, wherein the plurality of communication terminal devices include a communication unit that communicates with another communication terminal device via the conductor wire, and an encryption used for encryption and decryption of the communication signal. A distribution instruction receiving unit for receiving a distribution instruction for instructing key distribution; and when the distribution instruction for instructing distribution of the encryption key is received by the distribution instruction receiving unit, the communication unit transmits the encryption key to another communication An encryption key distribution processing unit to be transmitted to the terminal device, a setting instruction receiving unit for receiving a setting instruction for instructing the setting of the encryption key, and preset after the encryption key is received by the communication unit An encryption key setting unit configured to set the received encryption key as an encryption key for encryption and decryption of the communication signal when the setting instruction is received by the setting instruction receiving unit within a predetermined waiting time; The setting instruction receiving unit detects the presence or absence of a power supply voltage in the conductor wire, and when the power supply voltage is not detected within a predetermined waiting time set in advance after the encryption key is received The setting instruction is accepted.

  And a breaker device having a switch for opening and closing a connection between the external power supply that supplies the power supply voltage to the conductor wire and the conductor wire, and the encryption key distribution processing unit sends the encryption key to the communication unit. It is preferable to turn off the switch after a predetermined time elapses after transmission to another communication terminal device.

  The plurality of communication terminal devices preferably further include a setting notification unit that notifies that the encryption key has been set when the encryption key is set by the encryption key setting unit. .

Further, the breaker device according to the present invention is an encryption in which a plurality of communication terminal devices are communicably connected to each other using an encrypted communication signal via a conductor line shared for supply of power supply voltage and communication. A breaker device having a switch for opening and closing a connection between an external power supply for supplying the power supply voltage to the conductor wire in the communication system and the conductor wire,
A communication unit that performs communication with the plurality of communication terminal devices via the conductor wire;
A distribution instruction receiving unit for receiving a distribution instruction for instructing distribution of an encryption key used for encryption and decryption of the communication signal;
An encryption key distribution processing unit for transmitting the encryption key to the plurality of communication terminal devices by the communication unit when a distribution instruction for instructing distribution of the encryption key is received by the distribution instruction receiving unit;
The encryption key distribution processing unit transmits the encryption key to the plurality of communication terminal devices by the communication unit, and then turns off the switch to set the encryption key after a predetermined time has elapsed .

  In the encryption communication system, the encryption key setting method, and the communication terminal device configured as described above, when a distribution instruction for instructing distribution of the encryption key is received by one of the plurality of communication terminal devices, the encryption key is received. It is transmitted to other communication terminal devices. Then, when a setting instruction for setting the encryption key is received within a predetermined time after the encryption key is received by another communication terminal device, the received encryption key is used to encrypt the communication signal. Set as an encryption key for encryption and decryption, after the user issues a distribution instruction to one communication terminal device, the user sets the encryption key within a predetermined time. By giving the instruction, it is possible to easily set the encryption key only to the desired communication terminal device.

  Further, according to the breaker device having such a configuration, when the distribution instruction for instructing the distribution of the encryption key is received by the distribution instruction receiving unit, the encryption key is transmitted to the plurality of communication terminal devices via the conductor line. It is possible to easily set the encryption key only to the communication terminal device to which the power supply voltage is supplied via the switch.

  Embodiments according to the present invention will be described below with reference to the drawings. In addition, the structure which attached | subjected the same code | symbol in each figure shows that it is the same structure, The description is abbreviate | omitted.

(First embodiment)
FIG. 1 is a block diagram for explaining an example of the configuration of a communication terminal apparatus according to the first embodiment of the present invention and an encryption communication system using the same. In the cryptographic communication system 1 shown in FIG. 1, a plurality of communication terminal apparatuses 2-1 to 2-5 are connected to be communicable via a power line 3 (conductor line). Hereinafter, in this specification, when referring generically, it shows with the reference symbol which abbreviate | omitted the suffix, and when referring to an individual structure, it shows with the reference symbol which attached the suffix.

  In the dwelling unit A, communication terminal devices 2-1, 2-2, 2-3 are provided, and the communication terminal devices 2-1, 2-2, 2-3 are connected via the power line 3 so that they can communicate. . And the power line 3 is connected to the distribution line supported by the outdoor utility pole 5 via the breaker 4-1 accommodated in the distribution board 41, and the commercial power supplied from the distribution line is connected to the power line 3 through the power line 3. Are supplied to the communication terminal devices 2-1, 2-2, 2-3.

  Moreover, the communication terminal apparatus 2-4 and 2-5 are provided in the dwelling unit B, and the communication terminal apparatuses 2-4 and 2-5 are connected via the power line 3 so that communication is possible. The power line 3 is connected to a distribution line supported by the outdoor power pole 5 via a breaker (not shown) housed in the distribution board 42, and commercial power supplied from the distribution line is connected to the power line 3. Via the communication terminals 2-4 and 2-5.

  And since electric power is supplied to both dwelling units A and B via the power line 3 from a distribution line, as a result, the communication terminal device 2-1, 2-2, 2-3 provided in the dwelling unit A And communication signals are in communication with the communication terminal devices 2-4 and 2-5 provided in the dwelling unit B. Therefore, in the cryptographic communication system 1, the communication terminal devices 2-1, 2-2, 2-3 provided in the dwelling unit A and the communication terminal devices 2-4, 2-5 provided in the dwelling unit B are mutually connected. Different encryption keys are set, and the communication terminal devices 2-1, 2-2, 2-3 of the dwelling unit A and the communication terminal devices 2-4, 2-5 provided in the dwelling unit B use different encryption keys. By performing encrypted communication, information is prevented from leaking between dwelling unit A and dwelling unit B.

  Ciphers are not only commonly known as ciphers such as DES (Data Encryption Standard), AES (Advanced Encryption Standard), etc., but also simply such as those that perform EOR (exclusive OR) of data and encryption key. Some calculation may be performed using the data and the encryption key.

  FIG. 2 is a block diagram showing an example of the configuration of the communication terminal device 2 shown in FIG. 1 includes a control unit 20, a communication unit 21, a storage unit 22, a timer 23, a power supply voltage detection unit 24, a push button switch 25 (operation receiving unit), an LED (Light Emitting Diode) 26, two A secondary battery 27 and a power plug 31 are provided.

  The power plug 31 is a plug that is connected to, for example, a household outlet. When the user connects the power plug 31 to an outlet provided in a dwelling unit, the power plug 31 is connected to the power line 3. . The power plug 31 connects the communication unit 21, the power supply voltage detection unit 24, the secondary battery 27, and the power line 3.

  The communication unit 21 is a communication interface circuit that performs power line carrier communication. The communication unit 21 converts data from the control unit 20 into a communication signal according to the protocol of the power line carrier communication method, and transmits it to another communication terminal device 2 connected to the power line 3. It is a circuit that converts a communication signal transmitted from another communication terminal device 2 via the power line 3 into data in a format that can be processed by the control unit 20. As a protocol of the power line carrier communication system, various systems such as a simple control protocol (SCP) or an ECHONET power line A system or a power line B system can be used.

  The power supply voltage detection unit 24 is a circuit unit that detects the presence or absence of a commercial power supply voltage supplied from the power line 3 to the power supply voltage detection unit 24 through the power plug 31, and is configured using, for example, a comparator or an AD converter. For example, when the voltage is equal to or lower than a predetermined voltage set in advance, it is determined that the power supply voltage has disappeared, and a power interruption signal indicating that the power supply voltage has disappeared is output to the control unit 20.

  The secondary battery 27 is configured using, for example, a secondary battery such as a nickel hydride secondary battery or a lithium ion secondary battery, and is charged by the power supply voltage supplied from the power plug 31. A power supply voltage for operation is supplied to each part. Note that the secondary battery 27 has a time required for the control unit 20 to store the encryption key in the storage unit 22 when the power supply voltage supplied from the power plug 31 stops, for example, about 100 msec. What is necessary is just to be able to maintain the power supply voltage supplied to each part, and a capacitor | condenser may be used instead of a secondary battery.

  The storage unit 22 includes, for example, a volatile storage element such as a RAM (Random Access Memory) and a nonvolatile storage element such as a ROM (Read Only Memory) or a rewritable EEPROM (Electrically Erasable and Programmable Read Only Memory). It is configured using. The timer 23 is a timer circuit configured using, for example, a general-purpose timer IC (Integrated Circuit).

  The push button switch 25 is, for example, a so-called tact switch that is turned on when the user presses the button and turns off when the user releases the hand, and outputs a signal indicating the on / off to the control unit 20. The LED 26 is turned on or off according to a control signal from the control unit 20.

  The control unit 20 includes, for example, a CPU (Central Processing Unit) and its peripheral circuits, and executes a predetermined control program stored in advance in the storage unit 22 to thereby execute an encryption key generation unit 201, It functions as an encryption key distribution processing unit 202 and an encryption key setting unit 203.

  Next, the operation of the communication terminal apparatus 2 configured as described above and the cryptographic communication system 1 using the same will be described. 3 and 4 are flowcharts illustrating an example of the operation of the communication terminal device 2. For simplicity of explanation, an example in which the communication terminal device 2-1 distributes an encryption key to other communication terminal devices 2 will be described. First, the communication unit 21 enters a reception standby state (step S1), and if an encryption key is not received (NO in step S2), the state of the push button switch 25 is confirmed by the encryption key distribution processing unit 202 (step S3). If the push button switch 25 is off (NO in step S4), the process proceeds to step S1 again. If the push button switch 25 is on (YES in step S4), the encryption key distribution premode for confirming encryption distribution is performed. The process proceeds to step S5 to perform the operation.

  In this case, when the push button switch 25 is turned on without receiving the encryption key by the communication unit 21, the push button switch 25 functions as a distribution instruction receiving unit, and the ON operation is a distribution for instructing the distribution of the encryption key. It is accepted as an instruction.

  In step S2, if the encryption key is not received for a predetermined time, for example, 10 minutes, the process may proceed to step S3. As a result, even if the encryption key is distributed for the second time or later, if the previous encryption key was distributed for a predetermined time or more, the push button switch 25 is not received by the communication unit 21 without receiving the encryption key. As it is turned on, the process can proceed to step S5 to perform the operation of the encryption key distribution pre-mode.

  In the encryption key distribution pre-mode, if the push button switch 25 is not pressed again within a predetermined monitoring time set in advance, for example, 10 minutes, the encryption key distribution instruction is canceled and the encryption key is not distributed. . Specifically, the encryption key distribution processing unit 202 sets a monitoring time, for example, 10 minutes in the timer 23 and starts the timer 23 (step S5), and enters the encryption pre-mode (waiting for confirmation of the encryption key distribution instruction). The LED 26 is turned on to notify the user that it has become (step S6). In this case, the LED 26 functions as an encryption pre-mode notification unit that notifies that the encryption pre-mode has been entered.

  Next, the state of the push button switch 25 is confirmed by the encryption key distribution processing unit 202 (step S7). If the push button switch 25 is off (NO in step S8), it is confirmed whether or not the timer 23 has timed out. (Step S9) If the time has not expired (NO in Step S9), the monitoring time has not passed yet, so the process proceeds to Step S6 again. If the time has expired (YES in Step S9), the encryption key is distributed. Instead, the process proceeds to step S1 again.

  Thereby, for example, the user recognizes that the encryption key transmitted from the other communication terminal device 2 is received by the communication terminal device 2-1, and sets the encryption key to the communication terminal device 2-1. When the push button switch 25 is turned on as a setting instruction to instruct, since the display by the LED 26 notifies the encryption pre-mode, it can be seen that the user is different from the intended operation. If the user does not press 25, the initial state is returned again due to a time-out, so that it is possible to prevent the user from unintentionally distributing the encryption key.

  Next, when the user confirms the display by the LED 26 and presses the push button switch 25 to cause the communication terminal device 2-1 to distribute the encryption key, the push button switch 25 is turned on in step S8 (YES in step S8). Thus, the process proceeds to step S10 to execute the operation of the encryption key distribution mode for distributing the encryption key. In this case, the push button switch 25 functions as a setting instruction receiving unit, and the ON operation is received as a setting instruction for instructing the setting of the encryption key.

  In the encryption key distribution mode, the encryption key distribution processing unit 202 causes the timer 23 to distribute the encryption key to the timer 23, for example, 10 seconds which is sufficient for another communication terminal device 2 to perform the encryption key reception process. Is set and the timer 23 is started (step S10), an encryption key is generated by the encryption key generation unit 201 and stored in the storage unit 22 (step S11), and the encryption key generated by the encryption key generation unit 201 is It is set as a new encryption key.

  Further, the communication unit 21 broadcasts the encryption key generated by the encryption key generation unit 201 via the power plug 31 and the power line 3, and the other communication terminal devices 2-2-2 connected to the power line 3. -5 is distributed (step S12), until the timer 23 times out, that is, the transmission of the encryption key is continued for 10 seconds (NO in step S13), and when the timer 23 times out after 10 seconds (step S13) YES in S13), the transmission of the encryption key is terminated, and the process proceeds to Step S1 again.

  In this case, the certainty of reception of the encryption key by the other communication terminal apparatuses 2-2 to 2-5 can be improved by continuing the broadcast for a certain period of time. Note that the broadcast of the encryption key is not limited to an example in which the broadcast is continued for a certain period of time. For example, the broadcast of the encryption key may be performed once, may be a predetermined number of times set in advance, or is continued until the user presses the push button switch 25 again. You may do it.

  Next, the operation of the communication terminal apparatus 2-2 in which the encryption key transmitted from the communication terminal apparatus 2-1 is set will be described. First, in the communication terminal device 2-2, the communication unit 21 enters a reception standby state (step S 1), and the communication unit 21 receives the encryption key transmitted from the communication terminal device 2-1 and sets the encryption key. The process proceeds to step S20 shown in FIG. 4 to perform the operation in the encryption key setting mode (YES in step S2).

  In the encryption key setting mode, the reception is performed only when the push button switch 25 is pressed within a predetermined waiting time set in advance after the encryption key is received by the communication unit 21, that is, when a setting instruction is given. The encrypted encryption key is set as an encryption key for encrypting and decrypting the communication signal. Specifically, first, the encryption key received by the communication unit 21 is temporarily stored in the storage unit 22 by the encryption key setting unit 203 (step S20). Then, the encryption key setting unit 203 sets a waiting time, for example, 10 minutes in the timer 23 and starts the timer 23 (step S21), confirms the state of the push button switch 25 (step S22), and push button switch 25. Is off (NO in step S23), and if there is no power interruption signal indicating that the power supply voltage from the power supply voltage detection unit 24 is lost (NO in step S31), it is confirmed whether or not the timer 23 has timed out (step S31). S24) If the time has not expired (NO in step S24), the waiting time has not yet elapsed, so the process proceeds to step S22 again. On the other hand, if the time has expired (YES in step S24), the encryption key is not set again. The process proceeds to step S1.

  When the user depresses the push button switch 25 to set the encryption key in the communication terminal device 2-2 (YES in step S23), the process proceeds to step S25 to perform encryption key setting processing.

  As a result, the user operates the push button switch 25 in the communication terminal device 2-1 to distribute the encryption key to the other communication terminal device 2, and then the communication terminal device 2, for example, the dwelling unit A in which the encryption key is to be set. By depressing the push button switch 25 of the installed communication terminal devices 2-2 and 2-3 and instructing the setting, only the communication terminal device 2 that wants to set the encryption key is transferred to the encryption key setting process. For the communication terminal devices 2 that do not want to set the encryption key, for example, the communication terminal devices 2-4 and 2-5 installed in the dwelling unit B, the encryption key is returned to the initial state (step S1) after a predetermined waiting time has elapsed. Therefore, the encryption key can be easily set only for the desired communication terminal device 2.

  Next, the encryption key setting unit 203 notifies the user that a new encryption key has been received, and the LED 26 blinks, for example, to prompt the user to perform a confirmation operation (step S25). In this case, the LED 26 functions as a reception notification unit.

  Then, the state of the push button switch 25 is confirmed by the encryption key setting unit 203 (step S26). If the push button switch 25 is off (NO in step S27), it is confirmed whether or not the timer 23 has timed out (step S26). If it has not timed out (NO in step S28), since the waiting time has not yet elapsed, the process proceeds to step S25 again. If it has timed out (YES in step S28), the encryption key is not set again. The process proceeds to step S1.

  In this case, if the user does not press the push button switch 25 within a predetermined waiting time after the communication unit 21 receives the encryption key, the LED 26 will not blink, so that the user does not want to set the encryption key. In the terminal device 2, for example, the communication terminal devices 2-4 and 2-5 installed in the dwelling unit B, the LED 26 does not blink, and it is confirmed that the encryption key has been distributed. Can be concealed from others.

  On the other hand, for example, inconvenience occurs in the encryption key generation process in the communication terminal apparatus 2-1 and the process of transmitting the encryption key from the communication terminal apparatus 2-1 to the other communication terminal apparatus 2, and the encryption key is properly transmitted. If the communication terminal apparatus 2-2 has not received the encryption key when the user presses the push button switch 25 to set the encryption key, the push button switch 25 is not distributed. Is accepted as a distribution instruction for instructing the distribution of the encryption key (YES in step S4), and the LED 26 is turned on to notify the user that the encryption pre-mode has been entered (step S6). It is possible to know that the encryption key that should have been distributed to the communication terminal device 2-2, and to avoid erroneous setting of the encryption key.

  Next, when the user depresses the push button switch 25 to instruct the confirmation of the encryption key setting instruction in the blinking state of the LED 26, the push button switch 25 is turned on, the confirmation instruction is accepted, and the process proceeds to step S29 (step S27). YES) In this case, the push button switch 25 functions as a confirmation instruction accepting unit, and the ON operation is accepted as a confirmation instruction that instructs confirmation of the setting instruction.

  In step S29, the encryption key setting unit 203 stores the encryption key temporarily stored in the storage unit 22 as a new encryption key in the storage unit 22, and the encryption key is set (step S29). In order to notify the user that the encryption key has been set, for example, the LED 26 is changed from a blinking state to a lighting state. In this case, the LED 26 functions as a setting notification unit, and the user can confirm from the display of the LED 26 that the encryption key has been set.

  As described above, through the processing of steps S1 to S29, for example, in a dwelling unit or a construction site, the user (constructor) presses the push button switch 25 in one of the communication terminal devices 2, and shifts to the encryption key distribution pre-mode. By confirming that the LED 26 is turned on and pressing the push button switch 25 again, the encryption key can be distributed to other communication terminal devices 2. Then, only for the communication terminal device 2 for which an encryption key is desired to be set, only the desired communication terminal device 2 can be selected by pressing the push button switch 25 again while confirming that the LED 26 has flashed by pressing the push button switch 25. An encryption key can be set easily.

  In addition, after the user distributes the encryption key to the communication terminal device 2-1, the user may turn off the breaker 4-1 instead of pressing the push button switch 25 of the communication terminal device 2-2 or 2-3. . Specifically, when the user turns off the breaker 4-1, the power supply voltage supplied from the power line 3 to the power supply voltage detection unit 24 by the power plug 31 becomes equal to or lower than a predetermined voltage, and the power supply voltage disappears. A signal indicating this is output to the control unit 20. Then, in step S31, the encryption key setting unit 203 detects a signal indicating that the power supply voltage from the power supply voltage detection unit 24 is lost (YES in step S31), and the process proceeds to step S29, where the encryption key setting unit 203, the encryption key temporarily stored in the storage unit 22 is stored in the storage unit 22 as a new encryption key, the encryption key is set (step S29), and the user confirms that the encryption key has been set. For example, the LED 26 is turned on to notify the user.

  Even if the power supply voltage supplied to the communication terminal device 2-2 is interrupted when the breaker 4-1 is turned off, the power supply voltage for operation is supplied to each part in the communication terminal device 2 by the secondary battery 27. The communication terminal device 2-2 does not stop operating without setting the encryption key.

  In this case, the LED 26 functions as a setting notification unit, and the user can confirm from the display of the LED 26 that the encryption key has been set. Further, the power supply voltage detection unit 24 functions as a setting instruction reception unit.

  Thereby, the user does not need to individually press the push button switch 25 of the communication terminal device 2 to set the encryption key, and the dwelling unit connected to the breaker 4-1 is turned off by turning off the breaker 4-1. The communication terminal apparatus 2 in A can be collectively set with the encryption key, and the number of steps for setting the encryption key can be reduced.

  Even if the breaker 4-1 is turned off, only the communication terminal device 2 connected to the power line 3 under the breaker 4-1 can set the encryption key. The encryption key is not set in the communication terminal devices 2-4 and 2-5 installed in the other dwelling units B, and it is suppressed that the encryption key is erroneously set in the communication terminal device 2 of another house. Is done.

  Note that, for example, the communication terminal device 2 may include a microphone device, and the communication terminal device 2 within a range where a sound emitted by a user uttering a voice or hitting a hand may receive the sound as a setting instruction. For example, the communication terminal device 2 may include a light receiving unit, and may receive light as a setting instruction when receiving light with a specific wavelength such as infrared light or light with characteristic modulation.

  As a result, the encryption key is set in a lump for only the communication terminal device 2 within the range where the sound emitted by the user's voice or clapping is reached, or the user uses the dedicated light-emitting device to Thus, it is possible to set the encryption key only in the communication terminal apparatus 2 within the reach of, and to reduce the man-hour for setting the encryption key.

  Moreover, although the example which uses one pushbutton switch 25 as a distribution instruction | indication reception part, a setting instruction | indication reception part, and a confirmation instruction | indication reception part was shown, it separates as a distribution instruction | indication reception part, a setting instruction | indication reception part, and a confirmation instruction | indication reception part. The operation switch may be used. Moreover, although the example which uses LED26 as an encryption pre-mode alerting | reporting part, a reception alerting | reporting part, and a setting alerting | reporting part by the difference in the lighting and blinking operation was shown, for example, an encryption pre-mode alerting part, a reception alerting part, In addition, a separate indicator may be used as the encryption pre-mode notification unit, the reception notification unit, and the setting notification unit. For example, a liquid crystal display may be used instead of the LED 26.

  Moreover, although all the communication terminal apparatuses 2 in the encryption communication system 1 showed the example provided with the same structure, for example, the communication terminal apparatus for exclusive use which distributes an encryption key, and an encryption key are received from another communication terminal apparatus It is also possible to use a communication terminal device that does not distribute only. Also, one communication terminal device 2 may distribute the encryption key and the other communication terminal device may be a communication terminal device that does not distribute the communication key. A configuration using the apparatus 2 may be used. In this case, the dedicated communication terminal device that distributes the encryption key does not need to include the encryption key setting unit 203, and the communication terminal device that does not perform distribution includes the encryption key generation unit 201 and the encryption key distribution processing unit 202. There is no need to prepare.

(Second Embodiment)
Next, a breaker device according to a second embodiment of the present invention and a cryptographic communication system using the same will be described. The cryptographic communication system according to the present embodiment is different from the cryptographic communication system 1 shown in FIG. 1 in that a breaker device 4a is used instead of the breaker 4-1. FIG. 5 is a block diagram showing an example of the configuration of the breaker device 4a. The breaker device 4a shown in FIG. 5 is different from the communication terminal device 2 shown in FIG. 2 in the following points.

  That is, the breaker device 4a further includes a switch SW1 that opens and closes a connection between the power line 3 wired from the distribution line supported by the utility pole 5 and the power line 3 in the dwelling unit A, and does not include the encryption key setting unit 203. . The communication unit 21 is connected to the power line 3 in the dwelling unit A, and performs power line carrier communication with the communication terminal devices 2-1 to 2-3 in the dwelling unit A.

  Except for the differences in the operation of the encryption key distribution processing unit 202a as described later, the rest of the configuration is the same as that of the communication terminal device 2 shown in FIG. The operation of this embodiment will be described below.

  FIG. 6 is a flowchart showing an example of the operation of the breaker device 4a shown in FIG. The flowchart shown in FIG. 6 differs from the flowchart shown in FIG. 3 in that step S2 is not provided, and step S40 is further provided after step S13. Since the operations in steps S1 to S13 are the same as those in steps S1 to S13 shown in FIG.

  In steps S12 and S13, after the communication unit 21 continues to broadcast the encryption key for a time sufficient for the other communication terminal apparatus 2 to receive the encryption key, the encryption key distribution processing unit 202a switches the encryption key in step S40. In order that SW1 is turned off and the power supply to the communication terminal devices 2-1 to 2-3 in the dwelling unit A is detected by the power supply voltage detection unit 24 in the communication terminal devices 2-1 to 2-3, for example. After being shut off for 100 msec, which is a sufficient time, the switch SW1 is turned on (step S40).

  Then, in the communication terminal devices 2-1 to 2-3, the encryption key is set by the processing of steps S31 and S29 in FIG. 4 (step S29), and the user is notified that the encryption key has been set. For example, the LED 26 is turned on.

  Thereby, the user operates the push button switch 25 in the breaker device 4a to automatically distribute the encryption key, and automatically connects the encryption key to the communication terminal device 2 connected under the breaker device 4a in the dwelling unit A. Therefore, it is possible to reduce the man-hours for setting the encryption key. In addition, it is easy to confirm that a new encryption key has been set in the communication terminal devices 2-1 to 2-3 by turning on the LED 26.

  The breaker device 4a only needs to transmit an encryption key to the communication terminal device 2 connected under the circuit of the breaker device 4a, and the switch SW1 need not be turned off and on after the encryption key is transmitted.

It is a block diagram for demonstrating an example of a structure of the communication terminal device which concerns on the 1st Embodiment of this invention, and an encryption communication system using the same. It is a block diagram which shows an example of a structure of the communication terminal device shown in FIG. It is a flowchart which shows an example of operation | movement of the communication terminal device shown in FIG. It is a flowchart which shows an example of operation | movement of the communication terminal device shown in FIG. It is a block diagram which shows an example of a structure of the breaker apparatus which concerns on the 1st Embodiment of this invention. It is a flowchart which shows an example of operation | movement of the breaker apparatus shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Encryption communication system 2 Communication terminal device 3 Power line 4 Breaker 4a Breaker device 5 Utility pole 20 Control part 21 Communication part 22 Storage part 23 Timer 24 Power supply voltage detection part 25 Pushbutton switch 26 LED
27 Secondary Battery 201 Encryption Key Generation Unit 202, 202a Encryption Key Distribution Processing Unit 203 Encryption Key Setting Unit SW1 Switch

Claims (8)

An encryption communication system in which a plurality of communication terminal devices are communicably connected to each other using an encrypted communication signal via a conductor line shared for supply of power supply voltage and communication,
The plurality of communication terminal devices are:
A communication unit that communicates with another communication terminal device via the conductor wire ;
And distributing instruction receiving unit that receives a distribution instruction for instructing the distribution of cryptographic keys used to encrypt and decrypt the previous SL communication signals,
An encryption key distribution processing unit for causing the communication unit to transmit the encryption key to another communication terminal device when a distribution instruction for instructing distribution of the encryption key is received by the distribution instruction receiving unit ;
And the setting instruction acceptance unit that accepts a setting instruction to set before the Symbol encryption key,
When the setting instruction is received by the setting instruction receiving unit within a predetermined waiting time set in advance after the encryption key is received by the communication unit, the received encryption key is encrypted with the communication signal. And an encryption key setting unit that is set as an encryption key for decryption ;
When the setting instruction is received by the setting instruction receiving unit within a predetermined time after the encryption key is received by the communication unit, the fact that the encryption key has been received is notified. A reception notifying unit that does not perform the notification when the setting instruction is not received by the setting instruction receiving unit within the predetermined time after the encryption key is received by the communication unit;
A confirmation instruction accepting unit for accepting a confirmation instruction for instructing confirmation of the setting instruction accepted by the setting instruction acceptance unit;
The encryption key setting unit has received the confirmation instruction by the confirmation instruction reception unit after the notification that the encryption key has been received by the reception notification unit and within the waiting time. In this case, the received encryption key is set as an encryption key for encryption and decryption of the communication signal, and after the notification is performed, and within the waiting time, the confirmation instruction receiving unit If the confirmation instruction is not accepted by the above, the encryption key is not set . An encryption communication system in which a plurality of communication terminal devices are communicably connected to each other using an encrypted communication signal via a conductor line shared for supply of power supply voltage and communication,
The plurality of communication terminal devices are:
A communication unit that communicates with another communication terminal device via the conductor wire ;
And distributing instruction receiving unit that receives a distribution instruction for instructing the distribution of cryptographic keys used to encrypt and decrypt the previous SL communication signals,
An encryption key distribution processing unit for causing the communication unit to transmit the encryption key to another communication terminal device when a distribution instruction for instructing distribution of the encryption key is received by the distribution instruction receiving unit ;
And the setting instruction acceptance unit that accepts a setting instruction to set before the Symbol encryption key,
When the setting instruction is received by the setting instruction receiving unit within a predetermined waiting time set in advance after the encryption key is received by the communication unit, the received encryption key is encrypted with the communication signal. And an encryption key setting unit that is set as an encryption key for decryption ;
The plurality of communication terminal devices include an operation receiving unit that receives an operation instruction,
The operation reception unit
When the operation instruction is received without receiving the encryption key by the communication unit, it functions as the distribution instruction reception unit that receives the operation instruction as the distribution instruction;
The encryption functioning as a setting instruction receiving unit that receives the operation instruction as the setting instruction when the operation instruction is received within a predetermined waiting time set in advance after the encryption key is received. Communications system. An encryption communication system in which a plurality of communication terminal devices are communicably connected to each other using an encrypted communication signal via a conductor line shared for supply of power supply voltage and communication,
Wherein the plurality of communication terminals, Bei example a communication unit for performing communication with another communication terminal through the conductor wire,
One communication terminal device among the plurality of communication terminal devices is at least:
A distribution instruction receiving unit for receiving a distribution instruction for instructing distribution of an encryption key used for encryption and decryption of the communication signal;
An encryption key distribution processing unit that causes the communication unit to transmit the encryption key to another communication terminal device when a distribution instruction for instructing distribution of the encryption key is received by the distribution instruction receiving unit ;
The other communication terminal device is at least:
A setting instruction receiving unit for receiving a setting instruction for instructing the setting of the encryption key;
When the setting instruction is received by the setting instruction receiving unit within a predetermined waiting time set in advance after the encryption key is received by the communication unit, the received encryption key is encrypted with the communication signal. And an encryption key setting unit that is set as an encryption key for decryption ,
The setting instruction receiving unit
Detect the presence or absence of power supply voltage in the conductor wire,
An encryption communication system , wherein the setting instruction is received when the power supply voltage is not detected within a predetermined waiting time set in advance after the encryption key is received . An encryption communication system in which a plurality of communication terminal devices are communicably connected to each other using an encrypted communication signal via a conductor line shared for supply of power supply voltage and communication,
  The plurality of communication terminal devices include a communication unit that performs communication with another communication terminal device via the conductor wire,
  At least one communication terminal device among the plurality of communication terminal devices is:
  A distribution instruction receiving unit for receiving a distribution instruction for instructing distribution of an encryption key used for encryption and decryption of the communication signal;
  An encryption key distribution processing unit that causes the communication unit to transmit the encryption key to another communication terminal device when a distribution instruction for instructing distribution of the encryption key is received by the distribution instruction receiving unit;
  Other communication terminal devices excluding the one communication terminal device are:
  A setting instruction receiving unit for receiving a setting instruction for instructing the setting of the encryption key;
  When the setting instruction is received by the setting instruction receiving unit within a predetermined waiting time set in advance after the encryption key is received by the communication unit, the received encryption key is encrypted with the communication signal. And an encryption key setting unit that is set as an encryption key for decryption,
  The setting instruction receiving unit
  Detect the presence or absence of power supply voltage in the conductor wire,
  Receiving the setting instruction when the power supply voltage is not detected within a predetermined waiting time set in advance after the encryption key is received;
A cryptographic communication system characterized by the above. An encryption communication system in which a plurality of communication terminal devices are communicably connected to each other using an encrypted communication signal via a conductor line shared for supply of power supply voltage and communication,
  The plurality of communication terminal devices are:
  A communication unit that communicates with another communication terminal device via the conductor wire;
  A distribution instruction receiving unit for receiving a distribution instruction for instructing distribution of an encryption key used for encryption and decryption of the communication signal;
  An encryption key distribution processing unit for causing the communication unit to transmit the encryption key to another communication terminal device when a distribution instruction for instructing distribution of the encryption key is received by the distribution instruction receiving unit;
  A setting instruction receiving unit for receiving a setting instruction for instructing the setting of the encryption key;
  When the setting instruction is received by the setting instruction receiving unit within a predetermined waiting time set in advance after the encryption key is received by the communication unit, the received encryption key is encrypted with the communication signal. And an encryption key setting unit that is set as an encryption key for decryption,
  The setting instruction receiving unit
  Detect the presence or absence of power supply voltage in the conductor wire,
  Receiving the setting instruction when the power supply voltage is not detected within a predetermined waiting time set in advance after the encryption key is received;
  A cryptographic communication system characterized by the above. A breaker device having a switch for opening and closing a connection between an external power supply for supplying the power supply voltage to the conductor wire and the conductor wire;
  The encryption key distribution processing unit causes the communication unit to transmit the encryption key to another communication terminal device, and then turns off the switch after a predetermined time has elapsed.
  The cryptographic communication system according to any one of claims 3 to 5, wherein: The plurality of communication terminal devices further include a setting notification unit for notifying that the encryption key is set when the encryption key is set by the encryption key setting unit. The cryptographic communication system according to any one of claims 3 to 6 . The power supply voltage is applied to the conductor wire in an encryption communication system in which a plurality of communication terminal devices are connected to each other using a communication signal encrypted via a conductor wire shared for supply of power supply and communication. A breaker device having a switch for opening and closing a connection between an external power supply and the conductor wire,
A communication unit that performs communication with the plurality of communication terminal devices via the conductor wire;
A distribution instruction receiving unit for receiving a distribution instruction for instructing distribution of an encryption key used for encryption and decryption of the communication signal;
An encryption key distribution processing unit for transmitting the encryption key to the plurality of communication terminal devices by the communication unit when a distribution instruction for instructing distribution of the encryption key is received by the distribution instruction receiving unit;
The encryption key distribution processing unit causes the communication unit to transmit the encryption key to the plurality of communication terminal devices, and then turns off the switch to set the encryption key after a predetermined time has elapsed. Breaker device characterized by.

Images