JP5578032B2 - Communication device - Google Patents

Description

  The present invention relates to a communication apparatus that receives information transmitted by unidirectional communication.

  Conventionally, a technique for transmitting and receiving information by communication performed between terminals of each vehicle (hereinafter referred to as vehicle-to-vehicle communication) and communication performed between a vehicle terminal and a roadside device (hereinafter referred to as road-to-vehicle communication) has been known. Yes.

  If these vehicle-to-vehicle communication and road-to-vehicle communication are two-way communication, multiple handshake operations will be performed to exchange the certificates necessary to prove the reliability of the communication partner and to prevent tampering with the communication data and the keys necessary for concealment. By doing so, it is possible to discriminate fake communication data transmitted from a malicious impersonation terminal (hereinafter referred to as an unauthorized terminal).

  However, when these vehicle-to-vehicle communication and road-to-vehicle communication are broadcast-type communication (that is, unidirectional communication), false communication data transmitted from an unauthorized terminal is determined by performing the above handshake. There was a problem that could not.

  Therefore, as a means for solving this problem, a technique has been proposed in which fake communication data transmitted from an unauthorized terminal is discriminated only on the receiving side. For example, in Patent Document 1, a frame including a signature, a public key, and a public key certificate in addition to information related to a vehicle is transmitted from a transmission-side vehicle, and the reception-side vehicle receives the frame, and then public key certification is performed. A technique is disclosed that verifies a public key from a certificate to determine whether or not it is a correct public key, and verifies whether or not the contents of the frame have been tampered with using the signature and the public key.

JP 2009-81524 A

  However, the technique disclosed in Patent Document 1 has a problem that the load on verification processing on the receiving side increases. More specifically, the transmission of information from the vehicle terminal in the inter-vehicle communication is about 10 times per second, and the transmission of information from the roadside machine in the road-to-vehicle communication is about 70 times per second. May receive information from a plurality of communication partners, and may receive 1000 times or more per second. Since a lot of calculations are required for the verification process, if all the transmitted information is to be verified in real time, a huge amount of calculations must be performed at high speed.

  Even if the processor processing capability is further improved due to the advancement of semiconductor technology in the future, for example, the certificate and signature methods will be updated to prevent spoofing and tampering, which is necessary for verification processing. Since the amount of calculation increases, an increase in the load on verification processing on the receiving side will be a problem in the future.

  The present invention has been made in view of the above-described conventional problems, and an object of the present invention is to provide a communication device that can reduce a load caused by verification processing of information transmitted by unidirectional communication. It is in.

According to the communication apparatus of claim 1, the information derived from the other device received by the receiving means (that is, information wirelessly transmitted by one-way communication with at least one of verification information of a certificate and a signature) , It is necessary to verify all the information derived from other devices to be received, because the verification necessity judgment means judges whether or not the validity verification is necessary, and the verification is not performed for the information derived from the other devices that are judged to be unnecessary. Disappear. Therefore, it is possible to reduce the number of verifications in the communication device, and to reduce the load caused by the verification process of information transmitted by unidirectional communication.
In addition, since it becomes possible to determine the necessity of verification of other device-derived information according to the level of importance determined at the stage in the verification necessity determination means, the importance of the received other device-derived information Thus, it is possible to reduce the load caused by the verification process.
Furthermore, according to the communication device of claim 1, the higher priority is verified with priority, while the lower importance is omitted, so that the importance of received information from other devices is taken into consideration. However, the load caused by the verification process can be reduced. In addition, the information derived from other devices that are determined to be the second lowest level is verified only when there is a free space in the temporary storage means, so the load of the verification process exceeds a certain limit. It is possible to verify more information derived from other devices, while avoiding this.

  When judging whether or not the verification of the received information derived from the other device is necessary, the verification of the information derived from the other device based on the content of the information derived from the other device received by the receiving unit as in claim 2. It is preferable to adopt a mode for determining whether or not it is necessary. According to this, it becomes possible to determine the necessity of verification based on the content of the information derived from other devices.

  In the case of the second aspect, it is preferable that, as in the third aspect, the necessity of verification of the other equipment-derived information is determined based on the information on the position of the other vehicle. According to this, it is possible to determine whether or not verification is necessary based on information on the position of another vehicle. For example, verification of other equipment-derived information that is considered to be highly urgent and important for the host vehicle, such as information from other equipment that is close to the host vehicle and other vehicles that are close to the intersection. Can be determined to be necessary.

  In the case of the second aspect, as in the fourth aspect, it is determined whether or not the verification of the other equipment-derived information is necessary based on the information on the position of the other vehicle and the information on the movement of the other vehicle. It is preferable to set it as an aspect. According to this, it becomes possible to determine whether or not verification is necessary based on the information on the position of the other vehicle and the information on the movement of the other vehicle. For example, it is possible to judge that verification is necessary for information derived from other equipment that seems to be highly urgent or important for the host vehicle, such as information derived from other equipment approaching the host vehicle. Become.

  In the case of the second aspect, it is preferable that, as in the fifth aspect, it is determined based on the information on the freshness of the other device-derived information whether or not verification of the other device-derived information is necessary. . According to this, it becomes possible to determine the necessity of verification based on the information related to the freshness of the information derived from other devices. For example, it is possible to judge that verification is necessary for information derived from other equipment that is considered to be highly important for the host vehicle, such as information derived from other equipment that has a short time lapse after being generated and has high freshness. .

  In the case of the second aspect, as in the sixth aspect, based on the content of the other device-derived information, it is determined whether the other device-derived information is transmitted from an unauthorized transmission source, When it is determined that the information has been transmitted from an unauthorized transmission source, it is preferable to determine that the verification of the other device-derived information is unnecessary and discard the other device-derived information without performing the verification. According to this, since it becomes possible to discard without verifying other device-derived information determined to have been transmitted from an unauthorized source, it is possible to reduce the time and effort of verifying other device-derived information that is not reliable can do.

  When determining whether or not it is necessary to verify the received information derived from the other device, the necessity of verifying the information derived from the other device is determined based on the additional information added to the information derived from the other device as in claim 7. It is preferable to adopt a mode for judging the above. According to this, at least any one of the information regarding the type of the transmission source of the other device-derived information, the information regarding the type of the other device-derived information itself, and the information requesting hopping in the multi-hopping communication of the other device-derived information It becomes possible to determine whether verification is necessary based on the information.

  For example, based on information related to the type of transmission source of device-derived information, information on other devices that are considered to be highly urgent or important for the vehicle, such as information from other devices from emergency vehicles and roadside devices Can be determined to require verification. In addition, based on information related to the type of other device-derived information itself, other device-derived information that is considered to be less urgent or less important to the vehicle, such as information from other devices that is advertisement information, is verified. It becomes possible to judge that it is unnecessary. In addition, based on information that requests hopping in multi-hopping communication, information on other devices that are considered to be highly urgent and important for the vehicle, such as information from other devices that require hopping, is verified. Can be determined to be necessary.

  When determining whether or not the verification of the received other device-derived information is necessary, according to the frequency of receiving the other device-derived information transmitted from the same transmission source by the receiving means, as described in claim 8 It is preferable to adopt a mode for determining whether or not verification of the origin information is necessary. According to this, it becomes possible to determine the necessity of verification according to the reception frequency of the information derived from other devices from the same transmission source. For example, information derived from other equipment that seems to be highly important for the host vehicle, such as information derived from other equipment that has been long since the previous reception from the same transmission source or received for the first time, is verified. It becomes possible to judge that it is necessary.

  When determining whether or not the verification of the received other device-derived information is necessary, the verification of the other device-derived information is performed according to the received power when the other device-derived information is received by the receiving unit as in claim 9. It is preferable to adopt a mode for determining whether or not it is necessary. According to this, it becomes possible to determine whether or not verification is necessary according to the received power. For example, as the received power is higher, it can be said that the information is derived from another device from another vehicle closer to the own vehicle. Therefore, for the own vehicle having higher received power, such as information derived from another device received from another vehicle closer to the own vehicle. It is possible to judge that verification is necessary for information derived from other devices that are considered to be highly important.

According to the first aspect 0, depending on whether the verification of the other device from information received has been performed, changing any of the presence and use of the way of the use of the application software of other equipment from information be able to. For example, information derived from other devices that has not been verified can not be used for application software, or can be stopped for auxiliary use.

1 is a block diagram showing a schematic configuration of a driving support system 100. FIG. 1 is a block diagram showing a schematic configuration of a roadside machine 1. FIG. (A)-(c) is a schematic diagram for demonstrating the procedure of the production | generation of the packet in the case of transmitting delivery information. 3 is a block diagram showing a schematic configuration of a navigation device 2. FIG. It is a flowchart which shows the flow from the importance determination process in the vehicle side control apparatus 36 of the vehicle A to a verification necessity determination process. It is a table | surface which shows an example of the relationship between the kind of delivery information, the result of an importance determination process, a verification process, and an application process. It is a flowchart for demonstrating an example about each process of the verified packet and the unverified packet in a vehicle position update application.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a schematic configuration of a driving support system 100 to which the present invention is applied. A driving support system 100 shown in FIG. 1 includes a roadside device 1, a navigation device 2 mounted on a vehicle A, and a navigation device 2 mounted on a vehicle B.

  In the driving support system 100, information is exchanged by road-to-vehicle communication between the roadside device 1 and the navigation devices 2 of the vehicles A and B, or the navigation device 2 mounted on the navigation device 2 of the vehicle A and the vehicle B. It is possible to exchange information by vehicle-to-vehicle communication with the vehicle.

  In the following description, it is assumed that broadcast-type wireless communication (that is, wireless one-way communication) is performed from the roadside device 1 or the navigation device 2 of the vehicle B to the navigation device 2 of the vehicle A.

  The roadside machine 1 is fixed and installed at a predetermined location such as a roadside near an intersection, and has a function as a wireless communication device that performs road-to-vehicle communication. Here, a schematic configuration of the roadside machine 1 will be described with reference to FIG. FIG. 2 is a block diagram showing a schematic configuration of the roadside machine 1. As shown in FIG. 2, the roadside machine 1 includes a roadside machine side road-to-vehicle communication unit 11, a center communication unit 12, and a roadside machine side control unit 13.

  The roadside machine side road-vehicle communication unit 11 communicates with the navigation device 2. For example, when information such as the speed, acceleration, traveling direction, current position, and the like of the vehicle B is transmitted from the navigation device 2 of the vehicle B, the roadside device side road-to-vehicle communication unit 11 receives the information and receives the information. To the side control unit 13. Note that the speed, acceleration, and traveling direction information of the vehicle B corresponds to information related to the movement of another vehicle in the claims, and the current position information of the vehicle B corresponds to information related to the position of the other vehicle in the claims.

  In addition, when the roadside machine side road-to-vehicle communication unit 11 receives distribution information to be described later from the roadside machine side control unit 13, the roadside machine side road-to-vehicle communication unit 11 sends the distribution information to the navigation device of the vehicle A according to the instruction of the roadside machine side control unit 13. 2 is transmitted by wireless one-way communication. The roadside machine side road-to-vehicle communication unit 11 performs communication with the navigation apparatus 2 via, for example, a communication antenna or a communication device connected to the navigation apparatus 2.

  The communication between the roadside device 1 and the navigation device 2 may be configured to use, for example, VICS (registered trademark) (Vehicle Information and Communication System), DSRC (Dedicate Short Range Communication), wireless LAN, etc. It is good also as a structure performed by. The distribution information distributed from the roadside machine 1 includes, for example, obstacle information such as information on speed, acceleration, traveling direction, current position, etc. of pedestrians and other vehicles that may prevent the vehicle from traveling, roads, etc. Traffic information related to traffic such as regulatory sign information such as information on temporary stop locations regulated by signs and road markings, vehicle control information that instructs temporary stop at temporary stop locations, and advertising information that is advertising information, etc. There is a variety of information.

  The center communication unit 12 performs communication with an information center that manages distribution information in an integrated manner. The center communication unit 12 communicates with the information center via, for example, a network, acquires distribution information from the information center, and the speed, acceleration, and progress of the vehicle B received by the roadside device 1 from the navigation device 2 of the vehicle B. Send information such as direction and current position to the information center.

  The roadside machine side control unit 13 is configured as a normal computer, and has a well-known CPU, memory such as ROM and RAM, I / O, and a bus line for connecting these configurations (not shown). Is provided. The roadside machine side control unit 13 executes various processes based on various information input from the roadside machine side road-to-vehicle communication unit 11 and the center communication unit 12.

  For example, the roadside machine-side control unit 13 includes the distribution information acquired from the information center by the center communication unit 12 and the speed, acceleration, and traveling direction of the vehicle B acquired from the navigation device 2 of the B vehicle by the roadside machine side road-to-vehicle communication unit 11 Based on the distribution information such as the current position information, a packet for transmitting the distribution information by wireless one-way communication is generated.

  Here, with reference to FIG. 3A to FIG. 3C, a description will be given of a packet generation procedure in the case of transmitting distribution information. FIG. 3A to FIG. 3C are schematic diagrams for explaining a packet generation procedure when distribution information is transmitted.

  As shown in FIG. 3A, a message for transmission is generated based on the distribution information. Assume that the message is in plain text, not encrypted. The message may include, for example, the distribution information described above, the roadside machine ID for individually identifying the roadside machine 1, information generation time that is information on the time when the message was generated, and the like. Further, a packet type flag (F in the figure) is added to the rear part of the message.

  The packet type flag is additional information such as information related to the type of the message transmission source, information related to the type of the message itself, and information requesting hopping in the multi-hopping communication of the message (hereinafter referred to as hopping flag). For example, when the message transmission source type is a roadside machine, a roadside machine flag is added as information on the message transmission source type. In addition, when the type of the message itself is an advertisement, an advertisement flag is added as information on the type of the message itself. When the type of the message itself is vehicle control such as a pause instruction, a vehicle control flag is added. The

  Subsequently, as shown in FIG. 3B, an electronic certificate (hereinafter referred to as a certificate) and an electronic signature (hereinafter referred to as a signature) are added to the rear part of the packet type flag. The certificate referred to here is a root certificate issued by a third party organization, for example, and is data representing an authorized terminal. The signature is an electronic proof given to the message and is data for guaranteeing that the message has not been tampered with. And as shown in FIG.3 (c), the production | generation of the packet for transmitting delivery information is completed by adding a header to the head of a packet.

  Note that although only one of the certificate and the signature may be added, a configuration in which both the certificate and the signature are added to the message is more preferable from the viewpoint of improving security. These certificates and signatures correspond to the verification information in the claims.

  Returning to FIG. 2, the roadside machine side control unit 13 transmits the generated packet from the roadside machine side road-to-vehicle communication unit 11 to the navigation device 2 of the vehicle A. The roadside machine side control unit 13 is assumed to transmit a packet periodically (for example, about 70 times per second).

  The navigation device 2 is mounted on the vehicles A and B as described above. In addition to having navigation functions such as route search and route guidance, the navigation device 2 has, for example, a communication function for performing the above-described road-to-vehicle communication and vehicle-to-vehicle communication. The navigation device 2 of the vehicle A corresponds to the communication device of the claims.

  Here, a schematic configuration of the navigation device 2 will be described with reference to FIG. FIG. 4 is a block diagram showing a schematic configuration of the navigation device 2. As shown in FIG. 4, the navigation device 2 includes a position detector 21, a map data input device 26, a storage medium 27, an external memory 28, a display device 29, an audio output device 30, an operation switch group 31, a remote control terminal (hereinafter referred to as a remote control). ) 32, a remote control sensor 33, a vehicle-side road-to-vehicle communication unit 34, a vehicle-to-vehicle communication unit 35, and a vehicle-side control device 36.

  The position detector 21 includes an acceleration sensor 22 that detects the acceleration of the host vehicle, a gyroscope 23 that detects an angular velocity around the vertical direction of the host vehicle, and a wheel speed sensor 24 that detects the speed of the host vehicle from the rotational speed of each rolling wheel. , And a GPS receiver 25 for GPS (Global Positioning System) that detects the current position of the host vehicle based on radio waves from the artificial satellite, and periodically detects the current position and the traveling direction of the host vehicle. I do. Depending on the accuracy of each sensor, the position detector 21 may be configured as a part of the above-described ones, and a geomagnetic sensor, a steering rotation sensor, etc. (not shown) may be used.

  The map data input device 26 is loaded with a storage medium 27, and inputs various data including so-called map matching data, map data, and landmark data for improving the accuracy of position detection stored in the storage medium 27. It is a device for. The map data includes link data indicating roads and node data.

  A link is a link between nodes when each road on the map is divided by a plurality of nodes such as intersections, branches, and merge points. The link data is composed of data such as a unique number (link ID) for identifying the link, a link length indicating the length of the link, a link direction, a link orientation, and link start and end node coordinates (latitude / longitude). .

  On the other hand, the node data includes a node ID, a node coordinate, a node name, and a link ID of a link connected to the node, each node having a unique number for each node where roads on the map intersect, merge and branch. It consists of each data such as ID.

  The external memory 28 is a mass storage device such as a writable HDD. The external memory 28 stores a large amount of data and data that must not be deleted even when the power is turned off, and frequently used data is copied from the map data input device 26 and used. .

  The display device 29 displays text and images, and can be configured using a liquid crystal display, an organic EL display, a plasma display, or the like. The audio output device 30 is configured by a speaker or the like, and outputs audio, warning sound, or the like based on an instruction from the vehicle side control device 36.

  As the operation switch group 31, for example, a touch switch or a mechanical switch integrated with the display device 29 is used, and an operation instruction for various functions is given to the vehicle-side control device 36 by a switch operation. The remote control 32 is provided with a plurality of operation switches (not shown). By inputting various command signals to the vehicle side control device 36 via the remote control sensor 33 by the switch operation, the same functions as the operation switch group 31 are provided. It is possible to execute this for the side control device 36.

  The vehicle side road-to-vehicle communication unit 34 communicates with the roadside machine 1. For example, the vehicle-side road-to-vehicle communication unit 34 of the vehicle A receives the aforementioned packet transmitted from the roadside machine 1. In addition, the vehicle-side road-to-vehicle communication unit 34 of the vehicle B transmits information such as the speed, acceleration, traveling direction, and current position of the vehicle B to the roadside device 1. The speed information may be obtained from the wheel speed sensor 24, the acceleration information may be obtained from the acceleration sensor 22, and the traveling direction and current position information may be obtained from the position detector 21.

  The inter-vehicle communication unit 35 transmits / receives data to / from the inter-vehicle communication unit 35 of the navigation device 2 mounted on another vehicle by wireless communication (that is, performs inter-vehicle communication). For example, when the distribution information is sent from the vehicle-side control device 36, the inter-vehicle communication unit 35 of the vehicle B directs the distribution information to the navigation device 2 of the vehicle A according to the instruction of the road-side machine-side control unit 13. To transmit by wireless one-way communication. Further, the inter-vehicle communication unit 35 of the vehicle A receives the distribution information transmitted from the inter-vehicle communication unit 35 of the vehicle B and sends it to the vehicle-side control device 36 of the vehicle A. The inter-vehicle communication unit 35 may be configured to transmit and receive information through wireless communication such as a wireless LAN.

  For example, the vehicle-side road-to-vehicle communication unit 34 and the vehicle-to-vehicle communication unit 35 may be configured to perform communication using a communication antenna connected to the navigation device 2 or a communication device connected to the navigation device 2. Further, the vehicle-side road-to-vehicle communication unit 34 and the vehicle-to-vehicle communication unit 35 may be provided separately or may be provided integrally.

  The vehicle-side control device 36 is configured as a normal computer, and has a known CPU, a memory such as a ROM and a RAM, an I / O, and a bus line (none of which is shown) for connecting these configurations. Is provided. The vehicle-side control device 36 includes various information input from the position detector 21, the map data input device 26, the external memory 28, the operation switch group 31, the remote control sensor 33, the vehicle-side road-to-vehicle communication unit 34, and the vehicle-to-vehicle communication unit 35. Based on the above, processing as a navigation function, processing related to packet transmission, processing for determining the importance of distribution information included in a received packet, processing for determining whether packet verification is necessary, and the like are executed.

  For example, the vehicle-side control device 36 of the vehicle B uses information such as the speed, acceleration, traveling direction, and current position of the vehicle B obtained from the position detector 21 and the sensors 22 to 25 as distribution information, and uses this distribution information. Originally, a packet for transmitting distribution information by wireless one-way communication is generated. This packet generation is performed in the same manner as the packet generation in the roadside machine side control unit 13 described above.

  Hereinafter, a specific configuration in the packet transmitted from the vehicle B will be described, and the description of the same configuration as the packet transmitted from the roadside device 1 will be omitted. The message of the packet transmitted from the vehicle B may include, for example, the distribution information, the vehicle ID for individually identifying the vehicle B, the information generation time that is information on the time when the message was generated, and the like.

  As the packet type flag, an emergency vehicle flag is added as information related to the type of the message transmission source when the type of the message transmission source is an emergency vehicle, and the message transmission is performed when the vehicle is a general vehicle other than the emergency vehicle. A general vehicle flag is added as information about the original type.

  The vehicle-side control device 36 of the vehicle B transmits the generated packet from the vehicle-to-vehicle communication unit 35 of the vehicle B to the vehicle-to-vehicle communication unit 35 of the vehicle A. The vehicle-side control device 36 of the vehicle B is assumed to transmit a packet, for example, periodically (about 10 times per second or the like).

  The vehicle-side control device 36 of the vehicle A holds various application software (hereinafter referred to as an application) that uses distribution information included in the received packet, executes an application corresponding to the distribution information, and provides various services. To do. For example, an application that updates the position of the vehicle B based on information on the speed, acceleration, traveling direction, and current position of the vehicle B (hereinafter referred to as a vehicle position updating application), and the speed, acceleration, traveling direction, and current of the vehicles A and B There is an application that determines and notifies the contact risk of the vehicles A and B based on the position information. In addition, there is an application that presents the above-described obstacle information, regulatory sign information, advertisement information, and the like from the display device 29 and the audio output device 30.

  Further, when the vehicle side control device 36 of the vehicle A receives a packet from the vehicle B by the inter-vehicle communication unit 35 or receives a packet from the roadside machine 1 from the vehicle side road-to-vehicle communication unit 34, Importance determination processing for determining the importance of distribution information included in this packet in stages is executed. The message transmitted from the vehicle B or the roadside device 1 corresponds to other device-derived information in the claims, and the vehicle-side road-to-vehicle communication unit 34 or the vehicle-to-vehicle communication unit 35 of the vehicle A corresponds to the receiving means in the claims. .

  In the importance determination process, for example, the importance is divided into four stages, the highest importance is “emergency”, the second highest importance is “important”, and the second lowest importance is “normal”. ”, The stage with the lowest importance is determined as“ non-important ”.

  The importance level may be determined based on the content of the message included in the packet. As an example, the degree of importance may be determined based on information on the current position of the vehicle B. Specifically, the distance between the vehicle A and the vehicle B is calculated from the current position information of the vehicle A obtained from the position detector 21 of the vehicle A and the current position information of the vehicle B included in the packet. When the distance between the vehicle A and the vehicle B is equal to or less than a predetermined threshold, the vehicle B is regarded as a nearby vehicle, and the importance is determined as “important”. In addition, the vehicle B may be regarded as a distant vehicle, and the degree of importance may be determined as “normal”. The predetermined threshold mentioned here is a value determined in consideration of the risk of contact between the vehicle A and the vehicle B, and is a value that can be arbitrarily set.

  Further, the distance between the nearest intersection of the vehicle B and the vehicle B is calculated from the node data obtained from the map data input device 26 of the vehicle A and the current position information of the vehicle B included in the packet, and the intersection and the vehicle are calculated. A configuration may be adopted in which the importance is determined as “important” when the distance to B is equal to or less than a predetermined threshold, and the importance is determined as “normal” when not less than the predetermined threshold. Here, the predetermined threshold is a value that can be arbitrarily set.

  Furthermore, it is good also as a structure which determines importance based on the information of the current position of the vehicle B, and the speed, acceleration, and traveling direction information of the vehicle B. Specifically, the vehicle A speed, acceleration, traveling direction, and current position information obtained from the wheel speed sensor 24, acceleration sensor 22, and position detector 21 of the vehicle A, and the speed of the vehicle B included in the packet, The degree of approach between the vehicle A and the vehicle B is calculated from the acceleration, the traveling direction, and the current position information. Then, when the degree of approach between the vehicle A and the vehicle B is equal to or less than a predetermined threshold, the importance is determined as “important”, and when the degree of proximity is not equal to or less than the predetermined threshold, the importance is determined as “normal”. What is necessary is just to be the structure to do. The predetermined threshold mentioned here is a value determined in consideration of the risk of contact between the vehicle A and the vehicle B, and is a value that can be arbitrarily set.

  Moreover, it is good also as a structure which determines importance based on the information generation time of a message. Specifically, the elapsed time after the message is generated is calculated based on the information generation time included in the packet. If the elapsed time is less than or equal to the predetermined time, the importance is determined as “important” as the freshness is high, and if the elapsed time is not less than the predetermined threshold, the importance is determined as “normal”. It may be configured to determine "." Therefore, the information generation time corresponds to information on the freshness of the claims. The predetermined time here is a time that can be arbitrarily set.

  Furthermore, based on the content of the message included in the packet, it is determined whether the message is transmitted from an unauthorized transmission source such as a so-called impersonation terminal, and the importance is determined according to the determination result It is good.

  Specifically, a list of vehicle IDs and roadside machine IDs (hereinafter referred to as unauthorized terminal lists) used by unauthorized senders is stored in advance, and the vehicle ID and roadside machine ID included in the packet are unauthorized terminals. It is determined whether or not the message is transmitted from an unauthorized source depending on whether or not it exists in the list. If an ID exists in the unauthorized terminal list, it is determined that the ID is transmitted from an unauthorized transmission source, and the importance is determined as “non-important”. When the ID does not exist in the unauthorized terminal list, the importance is determined based on other elements such as the content of the message included in the packet without determining that the ID is transmitted from an unauthorized transmission source.

  The unauthorized terminal list may be obtained from the server that manages the unauthorized terminal list by the navigation device 2 through a communication module such as DCM or a mobile phone, or through vehicle-to-vehicle communication or road-to-vehicle communication. That's fine.

  Further, a change in the current position of the vehicle B is obtained based on information on the current position of the vehicle B and information on the speed, acceleration, and traveling direction of the vehicle B in a plurality of receptions, and whether or not the change is unnatural. It is good also as a structure which determines whether it is what was transmitted from the unauthorized transmission source according to. In this case, the change may be unnatural because the traveling locus of the vehicle B jumps in the middle or deviates beyond the error range from the position calculated from the speed and acceleration. If the change is unnatural, it is determined that it is transmitted from an unauthorized transmission source, and the importance is determined as “unimportant”.

  In addition, the importance level may be determined based on a packet type flag added to the message. As an example, when the above-described emergency vehicle flag or vehicle control flag is added, the importance is determined to be “emergency” on the assumption that the vehicle A must respond urgently. If the hopping flag is added, the importance is determined as “important” as an important message that must be transmitted to a long distance by hopping. Even when the roadside machine flag is added, the importance is determined as “important”. Furthermore, when the advertisement flag is added, the importance is determined as “non-important”.

  The importance level may be determined based on the frequency of receiving packets transmitted from the same transmission source. Whether or not the packets are transmitted from the same transmission source is discriminated by the vehicle-side control device 36 of the vehicle A from that transmitted from the same transmission source when the vehicle ID and roadside machine ID included in the message match. What is necessary is just to be the structure to do. The detection of the received frequency may be performed by the vehicle-side control device 36 of the vehicle A based on the received packet message and a timer circuit count (not shown). Therefore, the vehicle side control device 36 of the vehicle A corresponds to the reception frequency detecting means in the claims.

  For example, when the reception interval of packets received from the same transmission source is a certain time or more, or when it is a packet received for the first time from the same transmission source, the frequency of reception was below a predetermined threshold In this case, the importance is determined as “important” on the assumption that similar information is unlikely to be received. And, when the frequency of reception is not less than a predetermined threshold, such as when the reception interval of packets received from the same transmission source is less than a certain time, there is a high possibility that similar information has already been received. As a thing, the importance is determined as “normal”. The certain time and the predetermined threshold mentioned here are values that can be arbitrarily set.

  Further, the importance level may be determined based on the received power when the vehicle side road-to-vehicle communication unit 34 or the vehicle-to-vehicle communication unit 35 of the vehicle A receives the packet. The received power may be configured such that a detector is provided in the vehicle-side road-to-vehicle communication unit 34 or the vehicle-to-vehicle communication unit 35 of the vehicle A and is detected by the detector. Therefore, the vehicle side road vehicle-to-vehicle communication unit 34 and the vehicle-to-vehicle communication unit 35 of the vehicle A correspond to the received power detection means in the claims.

  As an example, when the received power is equal to or higher than a predetermined threshold, it is determined that the packet transmission source is nearby, the importance is determined as “important”, and when the received power is not equal to or higher than the predetermined threshold, The importance is determined as “normal” on the assumption that the transmission source is not nearby. This is based on the fact that, in vehicle-to-vehicle communication and road-to-vehicle communication, the transmission power is generally a constant value, so that the reception power increases as a packet is received at a position closer to the transmission source. When the transmission source is the vehicle B, the vehicle B is regarded as a nearby vehicle when the received power is equal to or greater than a predetermined threshold, and the vehicle B is regarded as a distant vehicle when the received power is not equal to or greater than the predetermined threshold. Further, the predetermined threshold mentioned here is a value that can be arbitrarily set.

  In the above-described example, a configuration in which two types of importance, “important” and “normal”, are determined based on a predetermined threshold, but is not limited thereto. For example, a configuration may be adopted in which importance other than “important” and “normal” is determined based on a plurality of threshold values. In this case, the degree of importance may be determined higher as the distance value becomes smaller, the degree of approach increases, the elapsed time becomes shorter, the frequency of reception becomes lower, or the received power becomes higher.

  Also, for the same message, importance such as message content, packet type flag, frequency of receiving packets from the same transmission source (hereinafter referred to as reception frequency), and reception power when receiving packets (hereinafter referred to as reception power). When the determination result of the importance level for each element for determining is different, the following may be performed.

  For example, if it is determined that the message was sent from an unauthorized source and the importance level is determined to be “non-important”, the importance level is set to “ It is determined as “not important”. In addition, when it is not determined that the information has been transmitted from an unauthorized transmission source, it may be configured to select the most important one of the determination results of each element. For example, when it is determined that the same message is normal from the content of the message but “important” is determined from the packet type flag, the determination result is “important”. In addition, when it is determined as “non-important” based on the advertisement flag, even if there is a determination result other than “non-important” due to other elements, the importance is determined as “non-important”. Also good.

  Further, the vehicle-side control device 36 of the vehicle A determines whether or not it is necessary to verify the validity of the distribution information included in the packet according to the high importance determined in the importance determination processing. Execute the process. Therefore, the vehicle side control device 36 of the vehicle A corresponds to the verification necessity determination means in the claims.

  Here, the flow from the importance determination process in the vehicle-side control device 36 of the vehicle A to the verification necessity determination process will be described with reference to FIG. FIG. 5 is a flowchart showing a flow from importance determination processing to verification necessity determination processing in the vehicle side control device 36 of the vehicle A. This flow is started when a packet is received by the vehicle-side road-to-vehicle communication unit 34 or the vehicle-to-vehicle communication unit 35 of the vehicle A.

  First, in step S1, the above-described importance level determination process is executed, and the process proceeds to step S2. In step S2, when the determination result of importance in the importance determination process is “emergency” (YES in step S2), the process proceeds to step S3. If the importance determination result in the importance determination process is not “emergency” (NO in step S2), the process proceeds to step S5.

  In step S3, it is determined that verification is necessary, and the process proceeds to step S4. In step S4, the corresponding packet is preferentially verified and stored in an electrically rewritable memory (hereinafter referred to as a temporary storage memory) such as a RAM of the vehicle side control device 36 of the vehicle A. Specifically, for example, the highest priority is added to the priority queue of the temporary storage memory, and the flow is terminated. Therefore, the vehicle side control device 36 of the vehicle A corresponds to the temporary storage means in the claims.

  In step S5, when the importance determination result in the importance determination processing is “important” (YES in step S5), the process proceeds to step S6. If the importance determination result in the importance determination process is not “important” (NO in step S5), the process proceeds to step S8.

  In step S6, it is determined that verification is necessary, and the process proceeds to step S7. In step S7, the relevant packet is stored in the temporary storage memory as verification in the order of storage in the temporary storage memory. Specifically, for example, a priority lower than “emergency” is added to the priority queue of the temporary storage memory, and the flow is terminated. Note that, for a packet whose determination result is “important”, for example, the same priority may be given uniformly, and verification may be performed in the order of addition to the priority queue.

  In step S8, when the determination result of the importance in the importance determination process is “normal” (YES in step S8), the process proceeds to step S9. Further, when the determination result of the importance level in the importance level determination process is not “normal” (NO in step S8), the process proceeds to step S12 as “non-important”.

  In step S9, it is determined whether there is an empty queue with priority in the temporary storage memory. If it is determined that there is an empty queue (YES in step S9), the process proceeds to step S10. If it is not determined that there is an empty queue (NO in step S9), the process proceeds to step S12.

  In step S10, it is determined that verification is necessary, and the process proceeds to step S11. In step S11, the relevant packet is stored in the temporary storage memory as verification in the order of storage in the temporary storage memory. Specifically, for example, the same priority as “important” is added to the priority-added queue of the temporary storage memory, and the flow ends. Note that the packets added to the priority queue with the same priority as “important” are verified in the order of addition to the priority queue, in the same manner as the packets determined to be “important”. In step S12, it is determined that verification is not necessary, and the flow ends.

  In the present embodiment, the configuration in which the importance level is divided into four levels is shown. However, the present invention is not necessarily limited to this, and may be divided into other multiple levels such as three levels or two levels. For example, when dividing into three stages, “normal” may be included in “important”, and “emergency”, “important”, and “non-important” may be included, and “important” may be included in “normal”. It is possible to use three stages of “emergency”, “normal”, and “non-important”. In addition, when it is divided into two stages, “Emergency” is included in “Important”, and “Normal” is included in “Non-important”, and it is divided into “Important” and “Non-important”. Good. In addition, what is necessary is just to set it as the structure performed like the above-mentioned as a process of the necessity determination of the verification according to a determination result.

  Returning to FIG. 4, the vehicle-side control device 36 of the vehicle A uses the certificate and signature included in the packet for the packet determined to be verified in the verification necessity determination process, and checks the validity of the packet. A verification process for performing verification is executed. The verification process is performed in the same manner as a known method, such as the verification process described in Patent Document 1.

  Of the packets that have been verified, the legitimate packets that have been verified for validity are used for the above-mentioned application processing (hereinafter referred to as application processing), and the invalid packets that have not been verified for validity are discarded. The A regular packet whose validity has been verified may be temporarily cached in a temporary storage memory, for example. According to this, even when verification of the same packet is requested by a plurality of types of applications, the cached verified packet can be used, and the load of verification processing can be reduced. it can.

  The importance determination process, the verification necessity determination process, the application process, and the verification process may be executed by the same processor, or may be executed by different processors.

  Here, the relationship between the type of distribution information, the result of the importance determination process, the verification process, and the application process will be described with reference to FIG. FIG. 6 is a table showing an example of the relationship between the type of distribution information, the result of the importance determination process, the verification process, and the application process.

  Among the types of distribution information in FIG. 6, emergency avoidance information is distribution information with an emergency vehicle flag added, and vehicle control information is distribution information with a vehicle control flag added. The roadside machine information is distribution information to which a roadside machine flag is added, the nearby vehicle information is distribution information regarded as that of a nearby vehicle, and the multihop request information is distribution information to which a hopping flag is added. It is.

  Further, the periodic transmission information of the distant vehicle includes periodic transmission such as no hopping flag or no urgent flag added to the distribution information regarded as the distant vehicle. Credit delivery information. The unauthorized vehicle information is distribution information determined to be transmitted from an unauthorized transmission source, and the advertisement information is distribution information to which an advertisement flag is added. Note that the types of distribution information shown in FIG. 6 are merely examples, and various other types exist.

  As illustrated in FIG. 6, when the type of distribution information is emergency avoidance information or vehicle control information, the importance is determined as “emergency”. In the verification process, verification is performed preferentially, and in the application process, processing is performed using a verified packet.

  When the type of distribution information is roadside machine information, nearby vehicle information, or multihop request information, the importance is determined as “important”. In the verification process, verification is performed in the order added to the queue of the temporary storage memory (that is, in the queue order), and in the application process, the process is performed using the verified packet.

  Furthermore, when the type of the distribution information is regular transmission information of a distant vehicle, the importance is determined as “normal”. And in the verification process, only when there is an empty queue in the temporary storage memory, the verification is performed in the order of the queue. In the application process, when there is an empty in the queue, the process is performed using the verified packet. If there is no space in the queue, it is processed as an unverified packet.

  Further, when the type of distribution information is unauthorized vehicle information or advertisement information, the importance is determined as “non-important”. In the verification process, verification is not performed, and in the application process, processing is performed as an unverified packet.

  Subsequently, processing of unverified packets will be described. While the distribution information included in the verified packet is used for application processing, the distribution information included in the unverified packet is not used for application processing, or used in an auxiliary manner in application processing. What is necessary is just to be the structure to do. In addition, the distribution information included in the unverified packet is used for application processing, or when there is a free space in the temporary storage memory queue, the unverified packet is verified and verified. It is good also as a structure used for an application process.

  For example, regarding the unverified packet when the type of distribution information is unauthorized vehicle information, the distribution information included in the unverified packet may be discarded without being used for application processing. Further, regarding the unverified packet when the type of distribution information is advertisement information, the distribution information included in the unverified packet may be used for application processing.

  Here, with reference to FIG. 7, an example of each processing of the verified packet and the unverified packet in the vehicle position update application in the vehicle-side control device 36 of the vehicle A will be described. FIG. 7 is a flowchart for explaining an example of the processing of the verified packet and the unverified packet in the vehicle position update application.

  The packet includes information on the speed, acceleration, traveling direction, and current position of the vehicle B as distribution information. According to the information on the current position of the vehicle B that was already included in the packet, It is assumed that the current position of the vehicle B has been registered / updated (hereinafter updated). This flow is started when the verification process is completed.

  First, in step S21, it is determined whether or not the target packet has been verified in the verification process. If the packet has been verified, it is determined that the packet has been verified (YES in step S21), and the process proceeds to step S22. If the packet has not been verified, it is determined that the packet has not been verified (NO in step S21), and the process proceeds to step S23.

  In step S22, the current position of the vehicle B is updated to the position according to the information on the speed, acceleration, traveling direction, and current position of the vehicle B included in the verified packet (that is, the position is updated), and the flow ends. . The updated current position of the vehicle B may be configured to be displayed on an electronic map of the display device 29, for example.

  In step S23, it is determined whether or not the elapsed time from the previous update of the current position of the vehicle B (that is, the previous update) is equal to or shorter than a predetermined time. The elapsed time may be counted by a timer circuit (not shown). The certain time mentioned here is a time that can be arbitrarily set, and may be, for example, 1 second. If it is determined that the elapsed time from the previous update is less than or equal to a certain time (YES in step S23), the process proceeds to step S24. On the other hand, if it is not determined that the elapsed time since the previous update is equal to or shorter than the predetermined time (NO in step S23), the process proceeds to step S26.

  In step S24, the current position of the vehicle B predicted based on the speed, acceleration, and traveling direction of the vehicle B included in the unverified packet is calculated from the current position of the vehicle B at the previous update time. It is determined whether the deviation from the current position of the vehicle B is equal to or less than a certain distance. The fixed distance here is a time that can be arbitrarily set, and may be, for example, 10 meters. If it is determined that the deviation of the current position from the previous update is equal to or less than a certain distance (YES in step S24), the process proceeds to step S25. If it is not determined that the deviation of the current position from the previous update is equal to or less than a certain distance (NO in step S24), the process proceeds to step S26.

  In step S25, the current position of the vehicle B at the time of the previous update is corrected (that is, the position is corrected) based on the speed, acceleration, and traveling direction of the vehicle B included in the unverified packet, for example, and the flow ends. In this way, in step S25, although the position update of the vehicle B to the position according to the distribution information included in the unverified packet is not performed, auxiliary use such as correction of the current position of the vehicle B is performed.

  In step S26, it is determined whether or not there is an empty queue with priority in the aforementioned temporary storage memory. If it is determined that there is an empty queue (YES in step S26), the process proceeds to step S27. If it is not determined that there is an empty queue (NO in step S26), the process proceeds to step S28.

  In step S27, unverified packets are verified according to the queue order. If the validity is verified (YES in step S27), the process proceeds to step S22. If the validity is not verified (NO in step S27), the process proceeds to step S28.

  In step S28, the unverified packet is discarded, and the flow is terminated without using the vehicle B speed update application, the vehicle B speed, acceleration, traveling direction, and current position information included in the unverified packet.

  According to the above configuration, the packet received by the vehicle side road vehicle-to-vehicle communication unit 34 or the vehicle-to-vehicle communication unit 35 of the vehicle A needs to be verified by the processes from the importance determination process to the verification necessity determination process. Since no verification is performed for a packet that is determined to be negative and verification is not necessary, it is not necessary to verify all the received packets. Therefore, the number of verifications in the navigation device 2 can be reduced, and it is possible to reduce the load caused by the verification process of information transmitted by unidirectional communication.

  In addition, since the necessity of verification of the packet is determined according to the level of importance determined at the stage in the importance determination process, priority is given to those that are considered to be urgent or important for the host vehicle. While verifying, omitting verification that seems to be less urgent or less important, it is possible to reduce the burden of verification processing while considering the importance of the distribution information contained in the received packet become.

  Furthermore, for packets that are determined to be “normal” in importance, verification is performed only when there is a free space in the priority storage queue of the temporary storage memory, so that the load of verification processing does not exceed a certain limit. However, it is possible to verify more packets.

  In the above-described embodiment, the configuration in which the communication device of the claims is applied to the navigation device has been described, but the configuration is not necessarily limited thereto. For example, a function for acquiring necessary information from the position detector 21, the map data input device 26, the sensors 22 to 25, and the like, and a packet transmitted from the roadside device 1 or another vehicle by wireless one-way communication are received. If it is a vehicle-mounted device provided with a function, it is good also as a structure applied other than a navigation apparatus.

  Further, the communication device of the claims is not limited to the configuration applied to the in-vehicle device, and may be configured to be applied to the roadside device 1. For example, the roadside machine side control unit 13 of the roadside machine 1 performs the processes from the importance determination process to the verification necessity determination process on the packet transmitted from the vehicle by wireless one-way communication, and whether the verification is necessary or not. It may be configured to determine. In this case, the roadside machine side road-to-vehicle communication unit 11 corresponds to the receiving means and the received power detection means in the claims, and the roadside machine side control unit 13 includes the reception frequency detection means, the verification necessity determination means in the claims, and This corresponds to temporary storage means.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims, and the technical means disclosed in different embodiments can be appropriately combined. Such embodiments are also included in the technical scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Roadside machine (communication apparatus), 11 Roadside machine side road-to-vehicle communication part (reception means, reception power detection means), 12 Center communication part, 13 Roadside machine side control part (Reception frequency detection means, verification necessity judgment means, temporary Storage means), 2 navigation device (communication device), 21 position detector, 22 acceleration sensor, 23 gyroscope, 24 wheel speed sensor, 25 GPS receiver, 26 map data input device, 27 storage medium, 28 external memory, 29 Display device, 30 audio output device, 31 operation switch group, 32 remote control, 33 remote control sensor, 34 vehicle side road-to-vehicle communication unit (reception means, reception power detection means), 35 vehicle-to-vehicle communication unit (reception means, reception power detection means) ), 36 Vehicle side control device (reception frequency detection means, verification necessity judgment means, temporary storage means), 100 driving support system

Claims (10)

Receiving means for receiving information derived from another device, which is information wirelessly transmitted by one-way communication with at least one of verification information of a certificate and a signature,
Based on the verification information added to the other device-derived information received by the receiving means, a communication device for verifying the validity of the other device-derived information,
Verification necessity judgment means for judging whether or not the verification is necessary for the information derived from the other device received by the reception means ;
Temporary storage means for temporarily storing the information derived from the other device waiting for the verification process ,
The verification is performed on the information derived from the other device determined to be necessary for the verification by the verification necessity determination unit, while the verification is performed on the information derived from the other device determined by the verification necessity determination unit. Is not ,
The verification necessity determining means determines the importance of the information derived from the other device received by the receiving means in four stages,
For other device-derived information determined to be the most important stage, it is determined that the verification is necessary, and stored in the temporary storage means as performing the verification preferentially,
As for the information derived from the other device determined that the importance is the second highest stage, it is determined that the verification is necessary, and the temporary storage is performed on the assumption that the verification is performed according to the storage order in the temporary storage unit. Stored in the means,
Regarding the information derived from the other device determined that the importance level is the second lowest stage, if there is a space for storing the information derived from the other device in the capacity of the temporary storage unit, the verification is necessary. Judging and storing in the temporary storage means as performing the verification according to the storage order in the temporary storage means, if there is no space to store the other device-derived information in the capacity of the temporary storage means, Judge that the verification is unnecessary, do not perform the verification,
The communication apparatus characterized in that it is determined that the verification is unnecessary for the information derived from the other device determined to be at the lowest level of importance, and the verification is not performed . In claim 1,
The communication apparatus according to claim 1, wherein the verification necessity determination unit determines whether the verification of the other device-derived information is necessary based on the content of the other device-derived information received by the receiving unit. In claim 2,
The communication device is mounted on a vehicle,
The other equipment-derived information includes at least information on the position of a vehicle other than the vehicle,
The verification necessity determination unit determines whether the verification of the other device-derived information is necessary based on information on the position of the other vehicle among the other device-derived information received by the receiving unit. A communication device. In claim 2 or 3,
The communication device is mounted on a vehicle,
The other equipment-derived information includes at least information on the position of a vehicle other than the vehicle and information on the movement of the other vehicle,
The verification necessity determination unit is configured to perform the verification of the other device-derived information based on the information on the position of the other vehicle and the information on the movement of the other vehicle among the other device-derived information received by the receiving unit. A communication apparatus characterized by determining necessity. In any one of Claims 2-4,
The other device-derived information includes at least information related to freshness of the other device-derived information, and the verification necessity determination means is based on the information related to the freshness of the other device-derived information received by the receiving means. And determining whether or not the verification of other device-derived information is necessary. In any one of Claims 2-5,
The verification necessity determination unit determines whether or not the other device-derived information is transmitted from an unauthorized source based on the content of the other device-derived information received by the receiving unit, and the unauthorized source When it is determined that the information is transmitted from the communication device, the verification regarding the other device-derived information is determined to be unnecessary, and the other device-derived information is discarded without performing the verification. In any one of Claims 1-6,
The wirelessly transmitted other device-derived information requires hopping in the information regarding the type of the transmission source of the other device-derived information, information regarding the type of the other device-derived information itself, and multi-hopping communication of the other device-derived information. Additional information that is at least one of the information to be added,
The verification necessity determination unit is configured to determine whether the verification is necessary for the other device-derived information based on the additional information added to the other device-derived information received by the reception unit. Communication device. In any one of Claims 1-7,
A reception frequency detection means for detecting the frequency at which the reception means receives the information derived from the other device transmitted from the same transmission source;
The communication apparatus according to claim 1, wherein the verification necessity determination unit determines whether the verification of the information derived from the other device received by the reception unit is necessary according to the frequency detected by the reception frequency detection unit. In any one of Claims 1-8,
Receiving power detection means for detecting received power when receiving information from another device in the receiving means,
The communication apparatus according to claim 1, wherein the verification necessity determination unit determines whether the verification of the information derived from the other device received by the reception unit is necessary according to the reception power detected by the reception power detection unit. In any one of claims 1 to 9
The communication device executes application software using the information derived from the other device,
Depending on whether or not the verification is performed on the information derived from the other device received by the receiving unit, the presence or absence of use of the other device-derived information in the application software and the method of using the information are changed. A communication device.

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