KR101550544B1 - Message Propagation Scheme of Vehicle-to-Vehicle by using a Density - Google Patents

Abstract

In the present invention, disclosed is a technology of communication between vehicles. A message propagation scheme by using density according to an embodiment of the present invention measures enables a user to easily detect a Sybil attack of illegally using IDs by counting the number of the vehicles existing on the road to measure the density (d) of vehicles and broadcasting traffic information (TI) by message propagation types (MPT=0, MPT=1, and MTP=2) by applying a density categorization based massage propagation scheme (DCMPS) or a density categorization based message propagation module. The message propagation scheme not only can more increase efficiency of data communication applied to a vehicular ad-hoc network system (VANET system) between vehicles, but also provides correct and highly reliable traffic information to drivers. Therefore, the message propagation scheme can help to raise awareness of safe driving and to reduce a traffic accident rate.

Description

{Message Propagation Scheme of Vehicle-to-Vehicle by using a Density}

(DCMPS) or a dense classification based message propagation module (DCMPM), which measures the vehicle density (d) by counting the number of vehicles existing on the road, To an inter-vehicle message propagation technique using a density that broadcasts traffic information (TI) by message propagation type (MPT = 0, MPT = 1, MPT = 2).

Recently, Intelligent Transportation System has been used for research to build a Smart Highway that pursues stability and efficiency. Such ITS can provide real-time traffic information, commercial services such as digital map and music through V2I (Vehicle to Infrastructure).

The ITS can provide driver safety information services such as vehicle collision avoidance and accident alert through V2V (Vehicle-to-Vehicle).

However, the conventional inter-vehicle communication system suffers from sacrificing security for better communication efficiency or drastically decreasing communication efficiency for security.

In the early days, a radio system was mainly used as a means of wireless communication between vehicles. In recent years, a mobile phone system equipped with a GSM or GPRS module has been widely used. However, the initial radio method was not effective in terms of security. Recently developed GSM and GPRS modules, or upcoming 3G modules, must have facilities for long distance communication. Long distance communication service providers must establish many base stations in the area to establish a wireless communication network. The equipment cost of such a wireless communication network is very high and it takes a lot of time to construct a network.

Furthermore, the conventional communication method has a geographical limitation that it can be performed only within the area where the base station is installed. In addition, the fee for using the service through the long-distance communication base station is very expensive. It is not reasonable to charge such high costs to users for short distance usage. These disadvantages cause users to be reluctant to use expensive facilities, and they are also hindering non-commercial use and development.

Recently, interest in traffic information has been increasing, and many related services are being provided. However, it is costly to collect traffic information and spread it. For example, it collects information from loop coils, surveillance cameras, traffic information sources, etc. However, installing and operating loop coils and surveillance cameras, it is very costly to recruit taxi drivers and general information sources and operate them as traffic information sources. It is taking.

In addition, a mobile communication network is used to propagate the collected information to the general user. Specifically, the control center transmits the information to the control center using the backbone network. The control center collects and processes the related information, and transmits the information to the navigation terminal having the TPEG (Transport Protocol Experts Group) using the digital multimedia broadcasting (DMB) do

In this case, it is difficult to activate the service since the user receiving the information must bear the amount of money for receiving the information through the mobile communication network.

In addition, in order to collect and provide traffic information, it is necessary to invest a lot of periodical facilities as described above, and there is a disadvantage that traffic information can not be obtained where no infrastructure is installed.

Korean Patent Publication No. 10-2009-0095410 Korean Patent Publication No. 10-2014-0058160 Korea patent registration number: 10-1251470-0000 Korea patent registration number: 10-0982298-0000

A first object of the present invention is to provide a vehicle-to-vehicle message propagation method using the density of the present invention. The first object of the present invention is to provide a vehicle- Collision avoidance, emergency warning, and road condition warning to the driver, thereby providing high quality vehicle safety service.

The second object of the present invention is to classify the roads according to the vehicle density (d) for smooth traffic flow and to use the DCMPS or the dense classification Based message propagation module (DCMPM) to generate first and second cluster keys (CK1, CK2) for identifying the identity between vehicles.

A third object of the present invention is to easily detect a Sybil attack that steals an ID by identifying the identity between vehicles with the first and second cluster keys CK1 and CK2.

A fourth object of the present invention is to provide a method and apparatus for filtering the frequently generated redundant information values in traffic information (TI), thereby improving the efficiency with respect to data communication applied to a Vehicle Ad hoc Network System (VANET System) .

A fifth object of the present invention is to accurately transmit the traffic information to the driver by setting the message propagation type using the vehicle density (d).

A sixth object of the present invention is to provide reliable traffic information (TI) to the driver through the message integrity verification process, thereby helping to reduce the safe driving and the traffic accident rate.

In order to achieve the above object, the present invention includes the following configuration.

In other words, the inter-vehicle message propagation method using the density according to the embodiment of the present invention is a method of estimating the vehicle density (d) by counting the number of vehicles existing on the road after defining the road length, (MPT = 0, MPT = 1, MPT = 2) using the DCMPS or DCMPM after setting the message propagation type according to the message propagation type (TI) is broadcasted with the traffic information (TI).

The vehicle-to-vehicle message propagation technique using the density of the present invention broadcasts information transmission between vehicles, prevention of collision, warning of an emergency, and warning of a road condition to a driver through collection and provision of real-time traffic information (TI) It gives the first effect to support safety service.

The present invention also provides a method and system for classifying roads according to vehicle density (d) for smooth vehicle traffic flow and using DCMPS or dense classification based message propagation module (DCMPS) The first and second cluster keys CK1 and CK2 for confirming the identity between the vehicles by using the DCMPM.

Further, the present invention confirms the identity between vehicles with the first and second cluster keys (CK1, CK2), thereby providing a third effect that can easily detect a Sybil attack that steals an ID.

The present invention also provides a method and system for filtering traffic information (TI) by filtering frequently occurring duplicate information values to improve efficiency of data communication applied to a VANET system (Vehicular Ad Hoc Network System) Effect.

Further, the present invention provides a fifth effect that accurately transmits the traffic information to the driver by setting the message propagation type using the vehicle density (d).

In addition, the present invention provides a driver with a highly reliable traffic information (TI) through a message integrity verification process, thereby providing a sixth effect that helps to reduce the safe driving and the traffic accident rate.

FIG. 1 is a view schematically showing an infrastructure and road conditions for carrying out an inter-vehicle message propagation technique using a density according to an embodiment of the present invention.
FIGS. 2A and 2A are views sequentially illustrating a process of selecting a temporary cluster and a process of selecting a cluster through the steps (a) to (f) with respect to vehicles entering the cluster according to an embodiment of the present invention.
3 is a flowchart illustrating a process of verifying traffic information (TI) and extracting total traffic information (ATI) from traffic information (TI) according to an embodiment of the present invention.
FIG. 4 is a detailed view illustrating a process of determining whether to receive traffic information (TI) in broadcasting between vehicles on a general road according to an embodiment of the present invention.
FIG. 5 is a detailed view illustrating a process of determining whether or not to receive traffic information (TI) in inter-vehicle broadcasting on a highway according to another embodiment of the present invention.
FIG. 6 is a detailed view illustrating a process of determining whether an accident notification message (ANM) is transmitted in broadcasting between vehicles when an accident occurs in a city center according to another embodiment of the present invention.

[Example]

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a view schematically showing an infrastructure and road conditions for carrying out an inter-vehicle message propagation technique using a density according to an embodiment of the present invention.

Referring to FIG. 1, an inter-vehicle message propagation technique using density is a method of estimating a vehicle density (d) by counting the number of vehicles 300 existing on a road after defining a road length, (MPT = 0, MPT = 1, MPT = 2) using the DCMPS or the DCMPM based on the dense classification based message propagation technique (DCMPM) Information (TI).

First, the DCMPS designates the cluster 400 only when the vehicle density d is greater than the predetermined threshold value c and the vehicles 300 move in the same direction, (RSU) 100 (RSU) instead of determining the cluster 400 when the vehicles 300 are moving in different directions while the vehicle 400 is smaller than the preset threshold value c, And propagates traffic information (TI). [Mathematical Expression 1] [Refer to FIG. 1]

[Reference Figure 1]

Traffic Information (TI) Structure

In the first step (1) according to the designation of the cluster 400, after the vehicles 300 entering the road or moving are designated as the cluster 400, the first cluster key CK1 is assigned to the leading vehicle in the cluster 400, And selects the temporary cluster header 210 as a temporary cluster header 210. [Figure 2a (a)], [Figure 2a (b)]

That is, the vehicle 16 becomes the temporary cluster header 210.

The temporary cluster header 210 generates a neighbor list Nlist by using the PID and propagates the group key GK to the vehicles 300 by adding the public keys PK of the vehicles 300, The controller 300 confirms the PID described in the neighbor list Nlist and then generates the second cluster key CK2 by adding the group key GK and the second registration issuance key SK2.

The second cluster key CK2 thus generated is a key having the same value. For example, as seen in FIG. 2B (e), the vehicle 14 generates a second cluster key CK2 with GK + SK2.

The temporary cluster header 210 performs an XOR operation on the designated PID number of the starter vehicle V12 having the largest state gap with respect to the road length among the first cluster key CK1 and the vehicles 300 to generate a cluster header message CH And the vehicle 300 decodes the cluster header message CH into the second cluster key CK2 to confirm that the latter vehicle V12 is the cluster header 200. [ See Figure 2b (f)]

The vehicles 300 generate traffic information TI imprinted with the second cluster key CK2 and transmit the generated traffic information TI to the cluster header 200 and the cluster header 200 uses the signature key (TI) of the traffic information (TI) 300 and then generates the total traffic information (ATI) in which the redundant or inconsistent information value is removed from the traffic information (TI) whose integrity is verified.

[Reference Figure 2]

Total Traffic Information (ATI) Structure

3, the cluster header 200 verifies the validity time with the timestamp included in the traffic information TI and verifies the signature only with respect to the traffic information TI within the validity time The second cluster key CK2 and the signature key are identical to each other, it is recognized that the vehicles 300 exist in the cluster 400 and the redundant information value is deleted.

The cluster header 200 regards the traffic information TI as falsified data and generates the aggregated traffic information ATI signed with the first registration issuance key SK1.

The first step (2) according to the designation of the cluster 400 adds a road number (Road No.), a first registration issue key (SK1), a first temporary value ( the encryption value CS generated by XORing the first temporary value nonce1 and the first registration issue key SK1 generated by the concatenation and hashing of the first temporary value nonce1 and the first temporary value non- 300 (see FIG. 2A (c)).

The second step of the cluster designation 400 is a step of XORing the second registration issuance key SK2 and encryption value CS transmitted from the DCMP server 120 for each of the vehicles 300 to generate a second temporary value non- And compares the verification value C obtained by concatenating the second registration issuance key SK2, the road No. and the second temporary value nonce2 with the hash function and the pulse value Mac.

When the verification value C is equal to the MAC value Mac, the vehicles 300 transmit the PID and the public key PK to the temporary cluster header and delete the non-equality value MAC. Reference

For example, the vehicle 13 delivers the PID (V13) and the public key (PK) to the vehicle 16, which is the temporary cluster header 210.

Subsequently, the DCMPM module based on the dense classification according to the embodiment of the present invention confirms the position of the vehicles 300 and sets u = 0 in the out-of-state and u = 1 in the urban, MPT is set to 1 if u = 0 and MPT is set to 1 if u = 0 and u = 0 when the vehicle density d is larger than the threshold value c and u = MPT is set to 2 if u = 1 and larger than the threshold value (c). [Equation 2] [Equation 3]

When MPT = 0, as shown in FIG. 4, the source vehicle 220 transmits the first traffic information TI1 during the critical time T, the second traffic information TI2 after the critical time T elapses, To the following vehicles 230, the RSU (Road Side Unit) 100, and Opposite Direction vehicles (not shown), respectively.

The following vehicles 230 and an RSU (Road Side Unit) 100 transmit the first traffic information TI1 and the second traffic information TI2 to additional Add vehicles in a relay form .

In addition, the destination vehicle 250, which is one of the additional vehicles, verifies whether the first traffic information TI1 and the second traffic information TI2 coincide with each other, and when the first traffic information TI1 matches the second traffic information TI2, The first traffic information TI1 and the second traffic information TI2 are deleted in the case of a discrepancy.

 As shown in FIG. 5, the source vehicle 220 propagates the first traffic information TI1 to the following vehicles 230 and the second traffic information (MPI) TI2) to Opposite Direction vehicles (240).

The following vehicles 230 propagate the first traffic information TI to additional Add vehicles.

One of the Opposite Direction vehicles 240 also propagates the second traffic information TI2 to the preceding vehicle (ex: second vehicle), which is another one of the opposite vehicles 240. [

The destination vehicle 250 compares whether the first traffic information TI1 transmitted to the additional following vehicle and the second traffic information TI2 received by the preceding vehicle coincide with each other, 1 traffic information TI1 and the second traffic information TI2 and deletes the first traffic information TI1 and the second traffic information TI2 at the time of discordance.

6, an RSU (Road Side Unit) 100 generates an accident notification message (ANM) when an accident occurrence message (AOM) is obtained through the vehicles 300 as shown in FIG. 6, RSU 110 and at least one vehicle 260 within the range of delivery of the vehicles 300. See Table 1 and Table 2,

field Item Message ID Incident Message = 01 Source IP address The IP address of the vehicle that generated the incident message Destination IP address IP address of neighbor RSU level Accident level

field Item Message ID Incident Notification Message ID = 02 Source RSU ID Incident Notification Message ID of RSI Message sequence number Sequence number of incident notification message Source IP address The IP address of the RSU in the incident scope Forwarding node X X coordinate of the relay vehicle Forwarding node Y Y coordinate of transit vehicle RSU hop Scope of message delivery according to risk

When at least one selection vehicle 260 delivers an incident notification message (ANM) to at least one neighboring vehicle 270, the RSU (Road Side Unit) 100 returns an incident notification message (ANM) Verify success.

Note that the node coordinate values of at least one selected vehicle 260 according to the broadcasting success are recorded in the vehicle direction table (VDT) of the RSU (Road Side Unit 100).

The at least one selection vehicle 260 or the at least one neighboring vehicle 270 compares the ID of the RSU (Road Site Unit) 100 existing in the transmission range area with the neighbor RSU ID and transmits an ANM propagation .

The neighboring RSU 110 repeatedly transmits an accident notification message (ANM) to at least one neighboring vehicle 270 existing in the neighboring coverage area 500 until the RSU hop count included in the incident notification message (ANM) becomes zero Thereby notifying the occurrence of a vehicle accident in the delivery range area 500. [
It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the present invention as defined by the following claims. It can be understood that it is possible.

RSU: 100 cluster header: 200
Vehicles: 300 Temporary cluster Headers: 210
Cluster: 400 Source vehicle: 220
Target vehicles: 250 Second-hand vehicles: 230
Vehicles in opposite directions: 240 Selected vehicles: 260
Neighboring Vehicle: 270 Neighbor RSU: 110
DCMP server: 120

Claims (14)

(D) is measured by counting the number of vehicles existing on the road after defining the road length, and the message propagation type is set according to the measured vehicle density (d), and then the density classification based message propagation technique (MPI = 0, MPT = 1, MPT = 2) for each message propagation type using the DCMPS or the DCMPM, Message propagation technique.
The method of claim 1, wherein the dense classification based message propagation technique (DCMPS)
The vehicle is designated as a cluster only when the vehicle density d is greater than a predetermined threshold value c and the vehicles move in the same direction,
When the vehicles are moving in different directions while the vehicle density d is smaller than a predetermined threshold value c, the traffic information TI is propagated using the roadside apparatus installed on the road instead of unknowing the cluster Inter - Vehicle Message Propagation Using Density.
3. The method according to claim 2, wherein the first step according to the cluster designation comprises:
The first cluster key (CK1) is assigned to the head vehicle in the cluster, and the temporary cluster header is selected as a temporary cluster header, and a road number (Road) is added to the hash function held in the temporary cluster header (Mac) generated by concatenating and hashing the first temporary value (nonce) and the first temporary value (nonce1) and the first temporary value nonce1 and the first temporary value (nonce1) SK1) is transmitted to the vehicles by an XOR operation of the vehicle-to-vehicle message propagation method using the density information.
4. The method of claim 3, wherein the second step of cluster designation comprises:
Generates a second temporary value (nonce2) by XORing a second registration issuance key (SK2) transmitted from the DCMP server to each of the vehicles and the encrypted value (CS), and outputs the second registration issuance key (SK2) (Road No.) and the second temporary value (nonce2) and compares the verification value (C), which is hashed by the hash function, with the Mac value (Mac)
When the verification value (C) is equal to the MAC value (Mac), the vehicles transmit the PID and the public key (PK) to the temporary cluster header, and delete the MAC value when they are not equal. Message propagation technique.
5. The method of claim 4,
The temporary cluster header generates a neighbor list (Nlist) using the PID and propagates the group key (GK), which is a sum of public keys (PK) of the vehicles, to the vehicles,
Wherein the vehicles generate the second cluster key (CK2) by checking the PID described in the neighbor list (Nlist) and adding the group key (GK) and the second registration issue key (SK2) Message Propagation Technique Using Inter - Vehicle.
6. The method of claim 5,
The temporary cluster header generates a cluster header message (CH) by XORing the designated cluster ID (CK1) and the designated PID number of the second vehicle having the largest state gap with respect to the road length among the vehicles, And,
Wherein the vehicles decode the cluster header message (CH) into the second cluster key (CK2) and confirm that the latter vehicle is a cluster header.
The method according to claim 6,
The vehicles generate the traffic information (TI) imprinted with the second cluster key (CK2) and transmit them to the cluster header,
The cluster header collects the traffic information (TI) of the vehicles using a signature key, and then transmits aggregate traffic information (ATI) in which duplicate or inconsistent information values are removed from the traffic information (TI) The message propagation method using the density of the vehicle.
8. The method of claim 7, wherein the cluster header
(TI), validates the validity time only with respect to the traffic information (TI) within the validity time,
If the second cluster key (CK2) and the signature key match each other, recognizes that the vehicles exist in the cluster and deletes the duplicated information value,
(ATI) signed with the first registration issuance key (SK1) after considering the traffic information (TI) as falsified data and deleting the traffic information Message propagation technique.
The method of claim 1, wherein the dense classification based message propagation module (DCMPM)
The MPT is set to 0 if u = 0 while the vehicle density d is smaller than the threshold value c by setting u = 0 in the outside of the vehicle and u = The MPT is set to 1 if the vehicle density d is larger than the threshold value c and u is equal to 0 and the MPT is set to 2 if the vehicle density d is larger than the threshold value c and u = Inter - Vehicle Message Propagation Using Feature Density.
10. The method of claim 9, wherein if MPT = 0,
The source vehicle transmits the first traffic information TI1 during the critical time T and the second traffic information TI2 after the critical time T to the following vehicles, Unit and Opposite Direction vehicles, respectively,
The following vehicles and an RSU (Road Side Unit) transmit the first traffic information TI1 and the second traffic information TI2 to additional Add vehicles in a relay form,
The destination vehicle which is one of the additional late vehicles verifies whether the first traffic information TI1 and the second traffic information TI2 match with each other and when the first traffic information TI1 matches the second traffic information TI2, 2 traffic information (TI2), and deletes the first traffic information (TI1) and the second traffic information (TI2) at the time of discordance.
10. The method of claim 9, wherein when MPT = 1,
The source vehicle propagates the first traffic information TI1 to the following vehicles and propagates the second traffic information TI2 to Opposite Direction vehicles,
The following vehicles propagate the first traffic information TI1 to the additional vehicles,
One of the Opposite Direction vehicles propagates the second traffic information (TI2) to the preceding vehicle, which is another one of the opposite vehicles,
The destination vehicle compares whether the first traffic information TI1 received from the additional late vehicles matches the second traffic information TI2 received from the preceding vehicle, Wherein the first traffic information (TI1) and the second traffic information (TI2) are deleted when the first traffic information (TI1) and the second traffic information (TI2) .
10. The method of claim 9, wherein when MPT = 2,
The road side unit (RSU) generates an accident notification message (ANM) when an accident occurrence message (AOM) is obtained through the vehicles, and transmits it to at least one selected vehicle existing in the area of the transmission range of the neighboring RSU and the vehicles and,
When the at least one selected vehicle delivers the accident notification message (ANM) to at least one neighboring vehicle, the failure notification message (ANM) is returned to confirm success in broadcasting. Message propagation technique.
13. The method of claim 12,
Wherein the node coordinate value of the at least one selected vehicle according to the broadcasting success is recorded in the vehicle direction table (VDT) of the RSU (Road Side Unit).
13. The method of claim 12,
The at least one selected vehicle or at least one neighboring vehicle compares the ID of the RSU (Road Site Unit) existing in the transmission range region with the neighbor RSU ID, and stops the propagation of the incident notification message (ANM)
The neighboring RSU repeatedly transmits the failure notification message (ANM) to the at least one neighboring vehicle existing in the neighboring coverage area until the RSU hop count included in the failure notification message (ANM) becomes 0, A method of propagating a message between vehicles using a density, characterized by informing that a vehicle accident has occurred in a range.

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