JP2008072441A - Power-line carrier communication apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power-line carrier communication apparatus capable of automatically setting identification information at a terminal device supporting power line communication in order to impart the identification information to the terminal device easily and at a low cost, even if a communicating modem is not incorporated into an in-home outlet installed at a house. <P>SOLUTION: A power-line carrier communication apparatus (parent modem) 1 is used for power line communication employing a power line 9 as a communicating medium. The apparatus comprises a communication control outlet 25 and a communication control portion 22. A power plug 28 of a terminal device 2A capable of performing power line communication can be connected to the communication control outlet 25. When the power plug 28 is connected to the outlet 25, the communication control portion 22 generates and stores automatically the identification information of the terminal device 2A, and transmits the identification information to the terminal device 2A. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a power line communication device used for power line communication using a power line as a communication medium.

  A power line communication system (hereinafter referred to as a PLC system) is a high-frequency signal (as a communication signal ranging from several kHz to several tens of MHz or more) on a power line through which a commercial current with a frequency of 50 Hz or 60 Hz flows. .) Is superimposed to perform communication. Such a PLC system has attracted attention as a system capable of transmitting and receiving large-capacity data using an existing power line (also called a distribution line or a light line) drawn into each house without using a dedicated communication line. ing.

In order to construct a network such as a LAN using the PLC system, it is necessary that power line communication devices (a PLC modem, a slave modem, an information home appliance, etc.) constituting the network have authentication information of the network. is there. The authentication information includes a network ID (SSID: Service Set Identifier) for specifying the network, an encryption key for encrypting a signal transmitted and received in the network, a house code, and the like.
Since the power line communication device included in the network has such authentication information, it is possible to perform communication by distinguishing data of another network and data of the own network.

Therefore, when a new network is to be constructed or when a new power line communication device is to be added to an existing network, a common authentication in the network is newly established for the power line communication device newly operating in the network. Information needs to be set. And when setting authentication information with respect to a new power line communication apparatus, it becomes a problem how to identify a new power line communication apparatus after distinguishing from other power line communication apparatuses.
That is, when notifying authentication information to a new power line communication apparatus that does not yet have authentication information, it is necessary to prevent unauthorized or unintentional acquisition of authentication information by another power line communication apparatus. For this purpose, it is important to distinguish a power line communication device to be newly added from other power line communication devices having no authentication information.

When the network is configured with the power line communication device, the setting of the SSID, the encryption key, and the house code is generally required manually by the user, so that the setting work is complicated and troublesome.
Therefore, in a home network system that communicates using a power line, a power line communication modem that superimposes a house code assigned to each home in advance on the power line by detecting the insertion of a power plug is built into the home outlet of the house. Thus, there has been proposed a home network system in which a house code is automatically set in each terminal device capable of power line communication with a power plug connected to the outlet (see Patent Document 1).
JP 2003-78456 A

However, in the home network system of Patent Document 1, a power line communication modem for setting a house code is built in a home outlet of a house, so installation work for the communication modem is necessary. Has the disadvantage of increasing.
Also, especially in the case of existing houses, the majority of cases where there is no space for installing a communication modem in the wall of the room, it is necessary to start with construction to secure that space, the installation cost of the modem Becomes enormous.

  In view of such circumstances, the present invention enables automatic setting of identification information in a terminal device capable of power line communication without performing installation work of a communication modem in a home outlet installed in a house. It is an object of the present invention to provide a power line communication apparatus that can easily and inexpensively give identification information to a device.

  The present invention is a power line communication device used for power line communication in which a power line is a communication medium, wherein a communication control outlet to which a power plug can be connected and the power plug of a terminal device capable of power line communication are And a communication control unit that generates and stores identification information of the terminal device and transmits the identification information to the terminal device when connected to an outlet.

According to the power line communication device of the present invention, the power line is provided with the communication control unit that automatically generates, stores, and transmits the identification information based on the connection of the communication control outlet and the power plug to the outlet. The identification information generated by the power line communication device can be automatically set in the terminal device by connecting a power plug of a terminal device (other power line communication device, information home appliance, etc.) capable of communication to an outlet.
For this reason, since identification information can be automatically set in the terminal device without installing a communication modem in a home outlet installed in the house, it is easy and inexpensive to assign identification information to the terminal device. Can do.

  In the power line communication apparatus of the present invention, it is preferable that the communication control outlet can be used as a service outlet for supplying power. In this case, even when the outlet for control communication is not used for automatic setting of authentication information, the power line communication apparatus can be used more effectively because it can also be used as a service outlet for power supply.

On the other hand, if a communication control outlet that automatically sets authentication information is provided just by connecting a power plug, such as the power line communication apparatus of the present invention, a terminal device is connected to the outlet without authorization from the network administrator for authentication. There is concern about so-called impersonation in which information is acquired, and then the authenticated terminal device is connected to a nearby power line to steal information in the network.
Therefore, in the power line communication device of the present invention, the communication control unit erases the storage of the authentication information of the terminal device when the communication with the terminal device for which the provision of the authentication information has been completed is not performed for a certain period of time. It is preferable to have the function of

  In this case, when communication with a terminal device to which authentication information is given is not performed for a certain period, the communication control unit of the power line communication device erases the storage of the authentication information of the terminal device. Even if the authentication information is acquired, if the period until the terminal device is connected to the power line again exceeds the predetermined period, it is no longer possible to communicate with the power line communication device. For this reason, information leakage due to impersonation can be prevented.

In the power line communication device of the present invention, the communication control unit generates and stores identification information of the plurality of terminal devices individually by connecting power plugs of the plurality of terminal devices to the outlet. The identification information is preferably transmitted to the plurality of terminal devices.
In this case, since the communication control unit generates, stores, and transmits identification information for a plurality of terminal devices connected to an outlet, automatic setting of the identification information for the plurality of terminal devices can be performed simultaneously. It is possible to set authentication information for the terminal device more efficiently.

  As described above, according to the present invention, it is possible to automatically set identification information such as a house code in a terminal device without installing a communication modem in an outlet installed in a house. Information can be given easily and inexpensively.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[Home network]
FIG. 1 shows an example of a home network (LAN) constructed using the power line communication device (parent modem) of the present invention.
In this network, power line communication devices 1, 2 and 3 are connected to in-house power lines 9a, 9b and 9c in the houses A, B and C, and independent networks (LANs) are provided in the houses A, B and C, respectively. ) Has been built. In the following, the networks constructed in the houses A, B, and C are referred to as a network A, a network B, and a network C, respectively.

The in-home power lines 9a, 9b, 9c are extended from the transformer 5 installed on the utility pole or the like to the houses A, B, C. The transformer 5 converts a medium voltage into a low voltage (for example, 200 V), and a medium voltage distribution line that distributes a medium voltage (for example, 6 kV) of a three-layer AC to the primary side thereof. 8 is connected, and a power line 9 is connected to the secondary side.
The power line 9 connected to the secondary side of the transformer 5 is a common power line common to a plurality of houses A, B, and C, and the home power lines 9a and 9b of the houses A, B, and C are connected to the common power line 9. , 9c are branched.

Each home power line 9a, 9b, 9c is appropriately provided with a home outlet 10, and the power line communication devices 1, 2, 3 are connected to any one of these outlets 10 so that the networks A, B, C are connected to each other. Has been built. Each power line communication device 1, 2, 3 transmits a PLC signal and receives power supply through power lines 9a, 9b, 9c.
Each of the power line communication devices 1, 2, and 3 constituting each network A, B, and C includes at least one parent modem 1, and this parent modem 1 corresponds to the power line communication device of the present invention.

The parent modem 1 communicates with a terminal device composed of the child modem 2 in the networks A, B, and C, the information home appliance 3 capable of power line communication, and the like by using a PLC signal. The modem 1 serves as an access point (AP) for the child modem 2 and the information home appliance 3 to perform power line communication. For this reason, the child modem 2 and the information home appliance 3 are the end points (EP) of the network system.
The parent modem 1 of this embodiment has a built-in broadband router function and can access an external network such as the Internet. When the parent modem 1 has a broadband router function, the optical fiber 7 or the ADSL termination device 6 is connected to the parent modem 1 via the signal line S1, and is connected to an external network via the termination device 6. Communication is possible.

[Configuration of parent modem and child modem]
FIG. 2 shows a basic configuration for power line communication between the parent modem 1 and the child modem 2.
Both the parent modem 1 and the child modem 2 have the same basic configuration, and a coupling circuit 20 that superimposes a PLC signal on the power line 9 and transmission / reception of the PLC signal transmitted to the power line 9 inside the housing 19. PLC transmission / reception unit 21 that performs modulation / demodulation processing, etc., communication control unit 22 that performs communication control to be described later, memory 23 that stores authentication information, and the like, and an LED that notifies the user of the setting processing state of authentication information Etc., and a display unit 24 composed of the above.

In addition to the basic configuration described above, the parent modem 1 includes a communication control outlet 25 that also functions as a service outlet, and a detection unit 26 that detects the connection of the power plug 28 to the outlet 25.
Each of the parent modem 1 and the child modem 2 includes a power plug 28 at the tip of a power cord 27 extending from the housing 19, and this power plug 28 is connected to the in-home outlet 10 of the houses A, B, and C. By connecting, it is connected to power lines 9a, 9b, 9c which are PLC signal transmission lines and power supply lines. Each of the modems 1 and 2 includes an Ethernet (registered trademark) cable connection port 29, and a PC (personal computer) 30 connected to the port 29 and communication based on the Ethernet (registered trademark). It can be performed.

The communication control unit 22 of each modem 1 and 2 distinguishes the networks A, B, and C of each house and has an SSID as a network ID for recognizing the own network A, B, or C. This network ID is transmitted by being included in the transmission data of the PLC signal, and it can be distinguished whether the received PLC signal is transmitted from the own network or transmitted from another network. Note that a house code may be used as the identification information of the networks A, B, and C.
Further, the communication control unit 22 of each of the modems 1 and 2 has encryption key data for encrypting the PLC signal. This encryption key is set differently for each of the networks A, B, and C so that the PLC signal cannot be read from devices outside the networks A, B, and C.

The authentication information such as the network ID, the encryption key, and the house code may be freely set by the user, but here, the parent modem 1 is configured to be automatically generated. This saves typing.
The automatically generated network ID is generated based on the MAC address assigned to the parent modem 1. More specifically, a network ID is generated by adding a random number to a MAC address. By creating a network ID in this way, it can be made unique and difficult to guess. In addition, the encryption key is generated by a random number, is difficult to be the same as the encryption key of other networks, and is difficult to be guessed by others.

When the detection unit 26 detects that the power plug 28 is connected to the communication control outlet 25, the communication control unit 22 of the parent modem 1 automatically generates identification information based on this detection. While being stored in the memory 23, the identification information is transmitted to the PLC transmitting / receiving unit 21.
Further, the communication control unit 22 of the parent modem 1 communicates with the terminal devices such as the child modem 2 and the information home appliance 3 once the authentication information has been given for a certain period (for example, several hours to one day). If not, the authentication information of the terminal device stored in the memory 23 is deleted.

(Configuration of detection unit)
3 and 4 show a configuration example of the detection unit 26 provided in the parent modem 1.
3 includes a pin-type detection switch 31 protruding from the central portion of the communication control outlet 25. The switch 31 is provided so as to be freely retractable along the insertion direction of the outlet 25. It has been. For this reason, when the power plug 28 is inserted into the outlet 25, the detection switch 31 is pushed into the inside of the housing 19, thereby detecting the connection of the power plug 28.

On the other hand, the detection unit 26 shown in FIG. 4 is configured by the communication control outlet 25 provided in the housing 19 so as to be freely withdrawn and retracted. For this reason, when the power plug 28 is inserted into the outlet 25, the outlet 25 is pushed into the inside of the housing 19, thereby detecting the connection of the power plug 28.
Note that the method for detecting the connection of the power plug 28 is not limited to these, and a minute thermal change, current change, and impedance change generated at the power terminal when the power plug 28 is connected to the outlet 25 can be detected by a heat detection sensor or current. A method of detecting with a detection sensor or an impedance detector can also be employed.

[How to set authentication information]
In the home network shown in FIG. 1, it is assumed that a parent network 1, a first child modem 2, and an information home appliance 3 are already connected to a certain network A, and the second child modem is connected to this network A. Assume that 2A is newly added. In this case, it is necessary to set authentication information such as a network ID of the network A and an encryption key used in the network A from the parent modem 1 to the newly added modem 2A.

  FIG. 2 shows a modem connection method for setting authentication information of the child modem 2A in the case of adding the child modem 2A as described above. In this embodiment, the parent modem that is the notification source of the authentication information is shown. This is done by connecting the power plug 28 of the child modem 2A to which the authentication information is notified to the outlet 25 for communication control.

When the power plug 28 is connected as described above, the detection unit 26 of the parent modem 1 detects the connection, and based on this detection, the communication control unit 22 of the parent modem 1 detects the network ID, encryption key, and the like. Automatically generate authentication information. This authentication information is stored in the memory 23 of the parent modem 1 and is transmitted from the outlet 25 to the child modem 2A through the power cord 27 for a predetermined time.
On the other hand, the communication control unit 22 of the child modem 2 </ b> A stores the authentication information in the memory 23 when the PLC transmission / reception unit 21 receives the authentication information.

When the memory 23 of the parent modem 1 and the child modem 2A stores the authentication information, the communication control unit 22 of each of the modems 1 and 2A blinks the display unit 24 such as an LED, thereby completing the setting of the authentication information for the user. Is notified.
Thereafter, the power plug 28 of the child modem 2A is removed from the outlet 25 of the parent modem 1, and the child modem 2A is inserted into any home outlet 10 in the network A, so that the child modem 2A becomes a new one in the network A. It will be added as a communication device.

  2 illustrates the case where the power plug 28 of the child modem 2A is connected to the outlet 25 of the parent modem 1 and the authentication information is set in the child modem 23. However, the information home appliance capable of power line communication is illustrated. 3 is connected to the outlet 25 of the parent modem 1, authentication information can be automatically set for the information home appliance 3.

Thus, according to the parent modem 1 of the present embodiment, the communication control unit that automatically generates, stores, and transmits the identification information based on the connection of the communication control outlet 25 and the power plug 28 to the outlet 25. 22 is connected to the outlet 25 by connecting the power plug 28 of the newly added child modem 2A, information home appliance 3 or the like to the outlet 25, so that the terminal device 2A, 3 Can be set automatically.
For this reason, identification information such as a network ID, an encryption key, and a house code is automatically set in the terminal devices 2A and 3 without installing a communication modem in the home outlet 10 installed in the houses A, B and C. Therefore, it is possible to easily and inexpensively give identification information to the terminal devices 2A and 3.

Also, according to the parent modem 1 of the present embodiment, the communication control outlet 25 can be used as a service outlet for supplying power, and therefore the communication control outlet 25 is not used for automatic setting of authentication information. However, there is an advantage that it can also be used as a service outlet for power supply and the parent modem 1 can be used effectively.
Furthermore, according to the parent modem 1 of the present embodiment, when communication with the terminal devices 2A, 3 such as a child modem to which authentication information is given is not performed for a certain period, the authentication information of the terminal devices 2A, 3 Therefore, if the period until the terminal devices 2A and 3 are connected to the power line 9 again exceeds the predetermined period, the terminal devices 2A and 3 can communicate with the parent modem 1. become unable.

  For this reason, even if there is an outsider who illegally acquires the authentication information generated by the parent modem 1 by connecting the terminal devices 2A and 3 to the outlet 25 of the parent modem 1 without the network administrator's permission, Is set to a relatively short period of time, the terminal device 2A cannot communicate with the terminal device 2A after a certain period of time until the terminal device 2A is reconnected to the power line 9, and information leakage due to impersonation is prevented in advance. be able to.

FIG. 5 shows a parent modem 1 according to another embodiment of the present invention.
In the parent modem 1 of this embodiment, the communication control unit 22 is configured such that the power plugs 28 of the plurality of child modems 2A (may be the information home appliance 3) are connected to the communication control outlet 25. The identification information of the plurality of child modems 2A is individually generated, and each identification information is stored in the memory 23 of the parent modem 1 and transmitted to the plurality of child modems 2A. Yes.

  In the connection example shown in FIG. 5, the power plug 36 of the table tap 32 is connected to the communication control outlet 25. The table tap 32 has a plurality of insertion ports 33 into which the power plug 28 of the child modem 2A can be inserted. More specifically, the table tap 32 includes an outlet main body 34 having a plurality of insertion ports 33, an extension cord 35 extending from the main body 34, and a power plug provided at the tip of the extension cord 35. 36.

The extension cord 35 of the table tap 32 is branched inside the main body 34 and connected to each insertion port 33. For this reason, by connecting the power plugs 28 of the plurality of child modems 2A to the respective insertion ports 33 of the main body 34, the plurality of child modems 2A are simultaneously connected to the outlet 25 for communication control of the parent modem 1. Can do.
Therefore, by connecting the power plug 36 of the table tap 32 to the outlet 25 of the parent modem 1 with the power plugs 28 of the plurality of child modems 2A inserted in the insertion ports 33 of the table tap 32, each child The authentication information for the modem 2A is automatically set, so that the authentication information setting operation for the child modem 2A can be performed more efficiently.

In FIG. 5, if the power plug of the information home appliance 3 is inserted into the insertion port 33 of the table tap 32, the authentication information for the information home appliance 3 can be automatically set simultaneously with the child modem 2A.
The present invention is not limited to the above embodiment.
For example, in the above embodiment, the parent modem 1 is provided with the detection unit 26 that detects insertion of the power plug 28, but a start button for starting the authentication information setting operation is provided on the casing 19 of the parent modem 1. The user can push the button to manually start the authentication information.

1 is an overall configuration diagram of a home network using power line communication. FIG. It is a figure which shows the connection method of a parent modem and the newly added child modem. It is an enlarged view of the outlet socket for showing the example of composition of a detecting part. It is an enlarged view of the electrical outlet for showing the other structural example of a detection part. It is a figure which shows another connection method of a parent modem and the newly added child modem.

Explanation of symbols

1 Parent modem (AP: Power line communication device)
2 Child modem (EP: Terminal device)
3 Information appliances (EP: Terminal device)
DESCRIPTION OF SYMBOLS 9 Power line 9a Residential power line 9b Residential power line 9c Residential power line 19 Housing | casing 20 Coupling circuit 21 PLC transmission / reception part 22 Communication control part 23 Memory 24 Display part 25 Outlet 26 for communication control 26 Detection part 28 Power plug 32 Table tap A In-home network B In-home Network C Home network

Claims (4)

A power line communication device used for power line communication in which the power line is a communication medium,
An outlet for communication control to which a power plug can be connected;
A communication control unit that automatically generates and stores identification information of the terminal device and transmits the identification information to the terminal device when the power plug of the terminal device capable of power line communication is connected to the outlet; A power line communication device comprising:   The power line communication device according to claim 1, wherein the communication control outlet can also be used as a service outlet for supplying power.   The communication control unit has a function of deleting storage of authentication information of a terminal device when communication with the terminal device for which the provision of the authentication information has been completed is not performed for a certain period of time. The power line communication device described.   The communication control unit individually generates and stores identification information of the plurality of terminal devices by connecting power plugs of the plurality of terminal devices to the outlets, and each identification information is stored in the plurality of terminals. The power line communication apparatus according to any one of claims 1 to 3, wherein the power line communication apparatus is transmitted to each apparatus.

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