JP2003324497A - Communication system and communication control unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a communication system and a communication control unit in which security against an abnormal operation of equipment is enhanced by stopping power supply to the equipment where abnormality is detected. <P>SOLUTION: In the communication system provided with a gateway 10 for detecting the equipment connected to communication networks (CL-LAN and OP-LAN) and abnormality in the equipment and a power management apparatus 40 for controlling the power supply to the equipment, the gateway 10 is provided with a transmission means for transmitting abnormal equipment information on the equipment wherein the abnormality is detected, the power management apparatus 40 is provided with a receiving means for receiving the abnormal equipment information, and the power supply to the equipment wherein the abnormality is detected is stopped based upon the received abnormal equipment information. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication system having a power supply controller capable of controlling power supply to each device connected to a communication network, and a communication controller capable of controlling the power supply controller. .

[0002]

2. Description of the Related Art In an apparatus, a machine, a vehicle, a facility or the like having a plurality of devices, the devices are often connected to each other to form a communication network. For example, in automobiles, a closed network in which devices other than the automobile manufacturer cannot connect and disconnect devices and an open network in which users can freely connect and disconnect devices are often connected via a gateway. Both networks are, for example, IEEE (Institute of Electri)
cal and Electronic Engineers) 1394 and IP o
compliant with IEEE 1394, IEEE1
High-speed data transmission of 394 and IP (Internet Protocol)
l) Packets can be transmitted.

In some cases, a power management system for controlling power supply to equipment is provided. The power management device controls the power supply to each device,
It is possible to stop the power supply to unused equipment.
For example, when a power management device is provided in an automobile, power is supplied to a corresponding device in response to a detection signal such as an ignition operation or the presence or absence of a human body in the automobile,
Stop the power supply. By stopping the power supply to unused equipment, it is possible to save energy and prevent malfunctions and the like. It is also considered that the power management device detects a chute for each power line and stops the power supply when a short circuit is detected.

Further, the gateway is a device for performing data transfer between networks, protocol conversion, buffering, authentication, etc., and is also capable of detecting an abnormality in the device and detecting unauthorized access from the outside. The gateway can perform a filtering process that stops the data transfer to the device in which the abnormality is detected or the data transfer related to the unauthorized access.

[0005]

However, a device in which an abnormality has occurred may send unexpected incorrect data, and unauthorized access attempts filtering through various methods. There may be cases where it is not possible to respond. Further, the filtering process may increase the load on the gateway, which may adversely affect other processes.

It is also conceivable to stop the power supply to the device in which the abnormality is detected or the device related to the unauthorized access by the power management device. However, since the power management device operates independently of the gateway, even if an abnormality or unauthorized access to the device is detected, the power management device does not stop the power supply.

As described above, when a device abnormality or unauthorized access occurs, there is a problem that only countermeasures such as gateway filtering processing can be taken.

The present invention has been made in view of the above circumstances, and provides a communication system capable of stopping the power supply to a device in which an abnormality is detected and improving the safety against abnormal operation of the device. The purpose is to

It is another object of the present invention to provide a communication system capable of improving the safety against unauthorized access by stopping the power supply to the equipment related to the unauthorized access.

It is another object of the present invention to provide a communication system capable of shortening the downtime of the device due to a temporary abnormality or unauthorized access.

It is another object of the present invention to provide a communication system capable of minimizing the influence on the connection of other equipment when the power supply to the equipment is stopped.

It is another object of the present invention to provide a communication system capable of stopping the power supply to the target device without affecting the connection of other devices.

It is another object of the present invention to provide a communication control device capable of transmitting information regarding a device in which an abnormality is detected to an external device.

Another object of the present invention is to provide a communication control device capable of transmitting information related to unauthorized access to an external device.

[0015]

A communication system according to a first invention is a device connected to a communication network, an abnormality detecting device for detecting an abnormality of the device, and a power supply control for controlling power supply to the device. In the communication system including a device, the abnormality detection device includes a transmission unit that transmits abnormal device information regarding a device in which an abnormality is detected, and the power supply control device includes a reception unit that receives the abnormal device information. It is characterized in that the power supply to the device in which the abnormality is detected is stopped based on the abnormal device information.

In such a communication system, when the abnormality detecting device detects an abnormality in the device, the transmitting means transmits the abnormal device information regarding the device in which the abnormality is detected to the power supply control device. The power supply control device receives the abnormal device information transmitted from the abnormality detection device by the reception means, and stops the power supply to the device in which the abnormality is detected. For example, when the power supply control device is configured to stop the power supply to the predetermined device in response to the predetermined signal, as the abnormal device information, the predetermined signal is transmitted from the abnormality detection device to Stop the power supply.

A communication system according to a second aspect of the present invention comprises a device connected to a communication network, an unauthorized access detection device for detecting unauthorized access to the device, and a power supply control device for controlling power supply to the device. In the communication system, the unauthorized access detection device includes a transmission unit that transmits unauthorized access information regarding the detected unauthorized access, and the power supply control device includes a reception unit that receives the unauthorized access information. Based on this, the power supply to the device related to the unauthorized access is stopped.

In such a communication system, the unauthorized access detection device, when detecting the unauthorized access, transmits the unauthorized access information regarding the unauthorized access to the power supply control device by the transmitting means. The power supply controller is
The acceptance unit accepts the unauthorized access information transmitted from the unauthorized access detection device and stops the power supply to the device related to the unauthorized access. For example, when an external communication device that connects to an external communication network such as the Internet is connected to the communication network and unauthorized access is being made from the external communication network, power supply to the external communication device is stopped.

A communication system according to a third aspect of the present invention is the communication system according to the first or second aspect, wherein the power supply control device re-supplies power to a device that has stopped power supply based on abnormal device information or unauthorized access information. The feature is that it is done.

In such a communication system, the power supply control device re-supplies power to the device whose power supply has been stopped based on abnormal device information or unauthorized access information. For example, the electric power is resupplied after a predetermined time has elapsed since the electric power supply was stopped. If no abnormality or unauthorized access is detected after resupply of power, it can be determined that recovery from a temporary abnormality or unauthorized access has ended, so power supply is continued. Regarding the device in which the abnormality is detected, when the number of times of resupply of power reaches a predetermined value, it can be determined that the device is out of order, and thus the power supply is maintained in a stopped state.

In a communication system according to a fourth aspect of the present invention, in any one of the first to third aspects of the present invention, the equipment is daisy chain connected or tree connected, and equipment for stopping power supply by the power supply control device. Is connected to the terminal side.

In such a communication system, each device is connected in a daisy chain or tree (tree type connection form).
Devices that are connected and that stop the power supply are connected to the terminal side. For example, in case of daisy chain connection,
The connection between the devices connected before and after the device whose power supply is stopped is disconnected. However, when the power supply to the terminal device is stopped, the disconnection does not occur. The closer the device is to the end, the smaller the number of devices affected by the disconnection. It is preferable to connect a device having a high power supply stop frequency or a device that does not cause a problem even when the power supply is disconnected to the terminal side.

A communication system according to a fifth aspect of the present invention is the communication device according to the fourth aspect, wherein the device includes a repeater, and the power supply control device is separate from the power supply which is stopped based on abnormal device information or unauthorized access information. Then, power is supplied to the repeater.

In such a communication system, each device is equipped with a repeater. For example, if each device is connected to the IEEE 1394 bus,
It has a repeater that relays between E1394 buses. The power supply control device supplies power (sub power) to the repeater of each device in a system different from power (main power) stopped based on abnormal device information or unauthorized access information. Even if the main power supply is stopped, the repeater is supplied with the sub power. Since the sub power is supplied to the repeater, the connection between the devices before and after the device whose main power is stopped is maintained.

A communication control device according to a sixth invention is a communication control device which is connected to a plurality of communication networks, controls data transmission between the communication networks, and further detects an abnormality of a device connected to each communication network, When an abnormality of the device is detected, it is characterized by comprising a transmitting means for transmitting abnormal device information regarding the device in which the abnormality is detected.

In such a communication control device, when an abnormality is detected in the equipment, the transmitting means transmits the abnormal equipment information regarding the equipment in which the abnormality is detected. For example, abnormal device information can be transmitted to the power supply control device that controls the power supply to the device connected to the communication network, and the power supply to the device in which the abnormality is detected can be stopped.

A communication control device according to a seventh aspect of the invention is connected to a plurality of communication networks, controls data transmission between the communication networks, and further detects unauthorized access. It is characterized in that it comprises a transmission means for transmitting the unauthorized access information regarding the access.

In such a communication control device, when the unauthorized access is detected, the transmitting means transmits the unauthorized access information regarding the unauthorized access. For example, the unauthorized access information can be transmitted to the power supply control device that controls the power supply to the device connected to the communication network, and the power supply to the device related to the unauthorized access can be stopped.

[0029]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be specifically described below with reference to the drawings showing the embodiments thereof. In the present description, an in-vehicle LAN provided in an automobile will be described as an example. (First Embodiment) FIG. 1 shows a communication system (vehicle-mounted LA) using a communication control device (gateway) according to the present invention.
An example of N) is shown. In-vehicle LAN (Local Area Network)
Is the CL-LAN and O connected to the gateway 10.
A P-LAN and a power management device (power supply control device) 40 are included. The power management device 40 is
The power supply (two-dot chain line) from the power supply unit 48 such as a battery to each device including the gateway 10 is controlled.

The CL-LAN is a LAN in which the automobile manufacturers limit the devices that can be connected and prohibit the connection and disconnection of the devices by other than the automobile manufacturers. OP-L
The AN is a LAN that allows automobile users to freely connect and disconnect devices. In this description, CL-LAN
A display 20, a speaker 22, a navigation system 24, a speedometer 26 and an external communication device 28 are connected to the OP-LAN, and an external communication device 30, an in-vehicle PC (Personal Computer) 32 and a DV are connected to the OP-LAN.
D (Digital Video (Versatile) Disk) player 34
Are connected.

Each device 20, 22, 24, 26, 28, 3
0, 32, and 34 have an IEEE 1394 interface and are connected to the IEEE 1394 bus. However, the connection of each device to the IEEE 1394 bus shown in FIG. 1 is performed by the daisy chain (Daisy Chai) of each device shown in FIG.
n) The connection is shown in a simplified form. It is also possible to connect each device in a tree. Although not shown, the external communication devices 28 and 30 are connected to an external communication network such as the Internet.

The IEEE 1394 is capable of high speed data transmission. In addition, RFC (Request For Comments) 2
734, IP over IEEE 1394 (IPv4) for transmitting IP packets on the IEEE 1394 bus.
over IEEE 1394),
It is also possible to transmit P packets.

The power management device 40 receives a detection signal of an ignition operation or a predetermined operation to a device, and supplies power to the corresponding device or stops the supply of power according to the received detection signal. Power supply / supply stop is controlled using a semiconductor, a relay, or the like.

The gateway 10 is a CL-LAN and an O.
Data transfer between P-LAN, protocol conversion, buffering and authentication are performed. As shown in FIG. 3, the gateway 10 includes IEEE 1394 interfaces 16 and 18 to which CL-LAN and OP-LAN are connected, and an IEEE 1394 interface.
It includes a control unit 12 that controls the transfer of data (packets) between the E1394 interfaces 16 and 18, and a storage unit 14 that stores various types of information used for packet transfer and the like. The storage unit 14 includes a flash memory.

The control unit 12 uses the CL-LAN and OP-L.
Packets sent from one of the ANs are forwarded to the other based on the header. The storage unit 14 stores a conversion table including information such as addresses relating to the source and / or destination of the packet, and the control unit 12 converts the address of the received packet based on the conversion table.

The gateway 10 is a CL-LAN and an O.
It operates as a device (abnormality detection device) that detects an abnormality in each device connected to the P-LAN. For example, the control unit 12
As a result, the IEEE 1394 interfaces 16 and 18 periodically send determination data to each device, and determine normality / abnormality based on the response from the device. In the present embodiment, each device calculates an XOR (Exclusive OR) between the determination data and its own address (device address), and returns the calculation result to the gateway 10. Control unit 1
2 acquires the address of each device from the conversion table, and creates determination data so that at least one value (bit) is inverted by the operation on the device side. In addition, the control unit 1
2 determines whether the calculation result returned from the device is correct (normal / abnormal).

A more complicated operation for the determination data can eliminate a correct response due to chance, but an arbitrary operation process can be performed according to the operation process of the device and the gateway 10. For example, it is possible to perform an OR operation or an AND operation, a checksum operation of determination data, or a CRC (Cyclic Redundancy Check) operation. Further, it is possible to use different judgment data every time.

The gateway 10 is, as shown in FIG.
A communication interface (transmission means) 44 for transmitting abnormal device information regarding a device in which an abnormality is detected is provided. Also,
The power management device 40 includes a communication interface (accepting unit) 42 that accepts abnormal device information. The abnormal device information includes a device identification number for identifying a device whose power supply is to be stopped by the power management device 40, a power supply / supply stop instruction, and the like. The power management device 40 stops the power supply to the device in which the abnormality is detected based on the abnormal device information received from the gateway 10.

The power management device 40 re-supplies the power to the device, which has stopped the power supply based on the abnormal device information, within a predetermined number of times. The devices that have detected anomalies include devices that cannot operate normally due to a failure and devices that have a temporary error due to the effects of power supply fluctuations, noise, static electricity, etc. In the case of a temporary abnormality, there is a high possibility of returning to normal by re-supply of power (reset).

Next, detection of a device in which an abnormality has occurred and stop of power supply will be described. In FIG. 4, the gateway 1
0 indicates an example of a procedure for detecting an abnormality of any device X and causing the power management apparatus 40 to stop the power supply to the device X. The control unit 12 of the gateway 10 acquires the address of the device X from the conversion table, creates determination data, and transmits the determination data to the device X (S10). The device X that has received the determination data calculates the XOR between the address of the device X and the determination data, and sends the calculation result to the gateway 10 (S12). Gateway 10 that received the calculation result
The control unit 12 checks whether the calculation result is correct (S1
4).

If the calculation result is correct, it can be determined that the device X is operating normally (S16: YES), and the abnormality of another device is continuously detected. If the calculation result is not correct or the calculation result is not sent, it can be determined that the operation of the device X is abnormal (S16: NO), and abnormal device information is transmitted from the gateway to the power management device (S1).
8).

The power management device 40 stops the power supply to the device X based on the received abnormal device information (S20). When the predetermined time has elapsed (S22: YES) from the stop of the power supply (S22: YES) and the number of times of resupply of power to the device X is less than or equal to the predetermined number (S24: YES), the power management device 40 supplies the power to the device X. Is supplied again (S26). Subsequent calculation (S10, S12, S14)
If no abnormality is detected in (S16: YES)
, The power supply to the device X is continued. If the number of times of re-supply exceeds the predetermined value (S24: NO), it can be determined that the device X is out of order, and the supply of electric power is stopped.

(Second Embodiment) In the first embodiment, the power supply to the device in which the abnormality is detected is stopped, but the communication system and communication control device of the present invention are related to unauthorized access. It is also possible to stop the power supply to the device. Hereinafter, the stop of the power supply of the device related to the unauthorized access will be described by taking the vehicle-mounted LAN (FIGS. 1 and 2) and the gateway (FIG. 3) similar to those of the first embodiment as an example.

The gateway 10 operates as a device for detecting unauthorized access (unauthorized access detection device). For example, a port scan for finding a network service port is detected, or a large number of access requests by the same transmission source or a large amount of data transmission is detected. To detect unauthorized access, the control unit 12 stores an access log or the like in the storage unit 14, and determines that the access is unauthorized if, for example, the number of accesses per unit time or the amount of transmitted data is larger than a predetermined value. Alternatively, it is possible to store a pattern of unauthorized access in the storage unit 14 and detect the unauthorized access based on the similarity to the pattern.

Communication interface 4 of gateway 10
Reference numeral 4 operates as a unit (transmitting unit) for transmitting the unauthorized access information regarding the detected unauthorized access. The communication interface 42 of the power management device 40 operates as a unit (accepting unit) for accepting unauthorized access information. The unauthorized access information is the power management device 40.
Includes a device identification number for identifying a device whose power supply is to be stopped, a power supply / supply stop instruction, and the like.

The power management device 40 stops the power supply to the device related to the unauthorized access based on the received unauthorized access information. For example, the external communication device 3
When an unauthorized access is made to the vehicle-mounted PC 32 via 0, the power supply to the external communication device 30 or the vehicle-mounted PC 32 is stopped. It is also possible to stop the power supply to the external communication device 30 and the vehicle-mounted PC 32.

Further, the power management device 40 sends the power supply to the device which has stopped the power supply based on the unauthorized access information.
Resupply power. For example, after a lapse of a predetermined time from the stop of power supply, power is supplied again.

FIG. 5 shows an example of a procedure in which the gateway 10 detects an unauthorized access and causes the power management apparatus 40 to stop the power supply to the device related to the unauthorized access. When the unauthorized access is detected (S36: YES), the gateway 10 transmits the unauthorized access information to the power management device 40 (S38).

Based on the received unauthorized access information, the power management device 40, for example, the external communication device 30.
The power supply to the device is stopped (S40). The power supply can be stopped not only for the external communication device 30 but also for an unauthorized access device.

After a lapse of a predetermined time from the stop of power supply (S4
2: YES), the power management device 40 is the device X
Power is re-supplied to (S46). After that, if no unauthorized access is detected (S36: NO), the power supply to the device X is continued.

In the above-described first and second embodiments, the gateway 10 and the power management device 40
Although and are directly connected (solid line), it is also possible to connect the power management device 40 to the CL-LAN and perform data transmission / reception between the two via the CL-LAN.

As shown in FIG. 2, when the devices are daisy chain connected, for example, when the power supply to the CL-LAN navigation system 24 is stopped, the connection between the speedometer 26 and the speaker 22 is disconnected. Will be done. Therefore, it is preferable to connect the external communication device 28 that frequently stops the power supply to the end portion side. When the power supply to the device connected to the terminal is stopped, the connection to other devices is not cut off. The equipment on the other end side has a smaller influence on the connection of other equipment when the power supply is stopped.

Further, each device may be provided with a repeater (repeater) to maintain the connection between the devices. For example, as shown in FIG. 6, an IE is added to the repeater unit 50 provided in the device.
The EE1394 bus is connected, the repeater unit 50 is connected to the data processing unit 52, and the I / O interface 54 is connected.
The input / output device 56 is connected to the data processing unit 52 via. Data processing unit 52 and I / O interface 54
Similarly to the above-described embodiment, the power is supplied from the power management device 40 (main power line: two-dot chain line in FIG. 6). The power of the system different from the main power supply line is supplied to the repeater unit 50 from the power management device 40 or another power supply unit (sub power supply line: one-dot chain line).

In the example shown in FIG. 6, when the power management device 40 stops the power supply, the power supply by the main power line is stopped, but the power supply by the sub power line is continued and the repeater unit 50 continues to operate. . Repeater section 50
6 is operating, the connection between the devices before and after the device shown in FIG. 6 is not broken.

In the above-described embodiment, the vehicle-mounted LA
Although N has been described as an example, the communication system and communication control device of the present invention can be used in any communication network to which devices whose power supply is controlled by the power management device are connected.

[0056]

According to the first aspect of the present invention, by stopping the power supply to the device in which the abnormality is detected, the erroneous data transmission from the device is stopped, and the safety against the abnormal operation of the device is improved. Can be increased.

According to the second aspect of the present invention, by stopping the power supply to the device related to the unauthorized access, it is possible to prevent the device from malfunctioning due to the unauthorized access and enhance the security against the unauthorized access.

According to the third aspect of the invention, it is possible to shorten the downtime of the device by resetting the device in which a temporary abnormality has occurred or restarting the device when the unauthorized access is completed. it can.

According to the fourth aspect of the invention, by connecting the device for stopping the power supply to the terminal side, it is possible to minimize the influence on the connection of other devices when the power supply is stopped.

According to the fifth aspect of the present invention, by providing the repeater in the device, it is possible to stop the power supply to the target device without affecting the connection of other devices.

According to the sixth aspect, it becomes possible to stop the power supply to the device by transmitting the information about the device in which the abnormality is detected to the power supply control device.

According to the seventh aspect of the present invention, it becomes possible to transmit the information regarding the unauthorized access to the power supply control device and stop the power supply to the device related to the unauthorized access.

[Brief description of drawings]

FIG. 1 is a block diagram showing an example of a communication system according to the present invention.

FIG. 2 is a block diagram illustrating a connection example of devices.

FIG. 3 is a diagram showing an example of a gateway.

FIG. 4 is a diagram showing an example of a procedure for stopping power supply to a device in which an abnormality is detected.

FIG. 5 is a diagram showing an example of a procedure for stopping power supply to a device related to unauthorized access.

FIG. 6 is a block diagram illustrating an example of a device.

[Explanation of symbols]

10 gateway (communication control device, abnormality detection device, unauthorized access detection device) 40 power management device (power supply control device) 42 communication interface (reception means) 44 communication interface (transmission means) 50 repeater unit (repeater)

Claims (7)

[Claims] 1. A communication system comprising a device connected to a communication network, an abnormality detection device for detecting an abnormality of the device, and a power supply control device for controlling power supply to the device, wherein the abnormality detection device comprises: The power supply control device includes a receiving unit that receives the abnormal device information, and the abnormality detection is performed based on the received abnormal device information. A communication system characterized in that power supply to equipment is stopped. 2. A communication system comprising a device connected to a communication network, a device for detecting unauthorized access to the device, and a power supply control device for controlling power supply to the device. The detection device includes a transmission unit that transmits unauthorized access information regarding the detected unauthorized access, the power supply control device includes a reception unit that receives the unauthorized access information, and relates to the unauthorized access based on the received unauthorized access information. A communication system, characterized in that power supply to a device that operates is stopped. 3. The power supply control device is configured to re-supply power to a device that has stopped power supply based on abnormal device information or unauthorized access information. Communication system. 4. The device is daisy chain-connected or tree-connected, and the device for stopping power supply by the power supply control device is connected to a terminal side.
The communication system according to any one of 1 to 3. 5. The device includes a repeater, and the power supply control device supplies power to the repeater in a system different from power supply stopped based on abnormal device information or unauthorized access information. The communication system according to claim 4, wherein the communication system is present. 6. A communication control device which is connected to a plurality of communication networks, controls data transmission between the communication networks, and further detects an abnormality of a device connected to each communication network, when an abnormality of the device is detected, A communication control device comprising: a transmitting unit that transmits abnormal device information regarding a device in which an abnormality is detected. 7. A communication control device which is connected to a plurality of communication networks, controls data transmission between the communication networks, and further detects unauthorized access, and when unauthorized access is detected, transmits unauthorized access information regarding unauthorized access. A communication control device comprising a transmission means.