KR20150007573A - Protocol Management System for Aggregating Massages based on certification - Google Patents

Abstract

The present invention relates to a technology related to encryption. A protocol management system for aggregating messages based on certification according to an embodiment of the present invention prevents a vehicle message from being counterfeited/falsified by certifying the vehicle message when the message is transmitted between vehicles, wherein a cause of counterfeiting/falsifying a vehicles message is a Sybil attack, and provides efficient communications by aggregating repetitive vehicle messages which often occur when a vehicle message is transmitted. As a result, a traffic information message is clearly certified and highly reliable information is provided. Also, communication efficiency is improved by reducing operation processing time when a message is transmitted between vehicles. In addition, by designing a certificate based message aggregation protocol (CMAP), which is based on a combination of encrypting and grouping and satisfies the security of a VANET and privacy requirements, even though the actual ID of a vehicle transmitting a traffic information message cannot be identified, the security of the VANET is enhanced and the efficiency of the network is improved by identifying a group to which the vehicle belongs, certifying the identity of the vehicle, and verifying the integrity of the message. The protocol management system for aggregating messages based on certification comprises: a repeater for roads for delivering a first public key (PKey_1) which a first vehicle has to a local VANET server when a vehicle-to-infrastructure (V2I) communication network is established and V2I communications between multiple vehicles and a local VANET server are relayed; the local VANET server for generating a local session key (SK_LV) using the PKey_1, and generating a first vehicle certificate (Cert_1) to certify the identification of the first vehicle using the SK_LV and a previously prepared local certificate (Cert_LV); and a VANET server for controlling, monitoring, and managing the state of traffic and operation of the repeater or the local VANET server using a wired/wireless communication network in real time.

Description

[0001] The present invention relates to an authentication-based message aggregation protocol management system,

More particularly, the present invention relates to an encryption-related technology, and more particularly, it relates to an encryption-related technology, in which a vehicle message is authenticated to prevent a vehicle message from being stolen or altered by a Sybil attack and a redundant vehicle message, And more particularly to an authentication-based message aggregation protocol management system that provides communication.

In recent years, ITS (Intelligent Transportation System) research has been actively conducted to apply IT technology to vehicles both domestically and internationally. In addition, the Vehicle Ad-hoc Network (VANET), which is the core technology of ITS, is an extension concept of MANET (Mobile Ad-hoc Network), which suggests various methods such as prevention of vehicle dispatch and traffic volume control.

In other words, VANET supports wireless communication between V2V (Vehicular-to-Vehicular) and V2I (Vehicular-to-Infrastructure) using intelligent vehicles and provides various services such as solving serious traffic congestion problems and preventing accidents As a basic goal. However, since the VANET is basically based on a network-based wireless environment, it inherits the security weaknesses inherent in the existing wireless network environment.

Furthermore, in VANETs, VANETs are vulnerable to malicious code because applications that are modified by malicious code threaten users' safety directly from messages exchanged between vehicles due to interference, counterfeit attacks, camouflage attacks, Reliability must be ensured.

  Therefore, in the VANET, if the contents of the message related to the safety operation are stolen and propagated by the attackers, deliberate accident may be caused. Therefore, not only the proper security mechanism but also abnormal or redundant traffic information And the communication efficiency of the VANET is lowered. Therefore, a mechanism capable of reducing the communication overhead is also needed.

VANET can be classified into internal and external networks. The internal network is generally called IVN (In-Vehicle Network), and the external network is classified into inter-vehicle communication network (V2V) and vehicle and infrastructure communication network (V2I).

The IVN is equipped with CAN, which connects and controls the body or chassis of the vehicle, MOST for connecting multimedia devices such as car audio, amplifiers, and CDPs, and X-by-Wire (Flexray) for connecting and controlling brakes or steering gear .

V2V provides vehicle collision alerting services and group communication by forming a vehicle network that can be configured without infrastructure to configure the network and communicate information based on inter-vehicle communication.

V2I can provide IP-based traffic information, security support, and download service by providing a communication network in which a vehicle and a wired / wireless communication infrastructure network are connected to support communication between a terminal and a server.

However, VANET is vulnerable to the following attacks.

- Sybil Attack: A single attacker appears on the network as multiple illusion nodes, increasing the chaos.

- Sending False Information: An attack that causes false information to be used by vehicles to contaminate other cars with false information within a certain network area.

- Jamming Attack: Attack that attacks the network communication by generating a signal that causes interference of communication of other vehicles in the certain network area by attack method such as DoS in general network.

- In-transit Traffic Tampering: An attack that interferes with automobile communication by deleting and modifying messages by an attacking car in the course of delivering messages during high-speed driving.

- Node Impersonation Attack: An attack that changes the information of a neighboring car to its own status information so that another car can recognize the wrong car.

- On-board Tampering: On-board tampering maliciously corrects sensor information such as speed and position by attacking the inside information of car such as speed, position, Attack provided.

Korea Patent Publication No. 10-2008-7025320 Korea Patent Publication No. 10-2007-0010536 Korean Registered Patent: No. 10-0683376-0000 Korean Registered Patent: No. 10-0682263-0000

A first object of the present invention is to provide an authentication-based message aggregation protocol management system of SKLC (Session Key based Local Certificate) which is a session key-based local certificate, (CMAP) including a Message Aggregation Protocol (MAP) for aggregating a traffic information message (TrafficMsg), which is a message, in order to clearly authenticate a traffic information message during message transmission between vehicles.

A second object of the present invention is to provide a method and system for securely providing highly reliable information by using a certificate based message aggregation protocol (CMAP) for verifying message integrity by a hash function operation when verifying a vehicle certificate, And to improve communication efficiency.

The third object of the present invention is to overcome the aforementioned weaknesses of the prior art, and it is an object of the present invention to provide a traffic information message (TrafficMsg) Based message aggregation protocol management system by installing CMAP (Certificate based Message Aggregation Protocol), which is designed to determine the unique ID of the vehicle, and to identify the vehicle, Defense).

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

That is, the authentication-based message aggregation protocol management system according to the embodiment of the present invention uses a V2I (Vehicle-to-Infrastructure) communication network established between a plurality of vehicles and a local VANET server, (V2I) communication between the plurality of vehicles and the local VANET server by mediating the V2I (Vehicle-to-Infrastructure) communication network with the first public key (PKey) held by the first vehicle ₁ ) to the local VANET server; Generating a local session key (SK _LV ) with the first public key (PKey ₁ ) and using the local session key (SK _LV ) and a non-authenticated local certificate (Cert _LV ) A local VANET server for generating a first vehicle certificate (Cert ₁ ) for authenticating the vehicle, and a VANET server for controlling, monitoring and managing the traffic state and operation state between the road relay or the local VANET server in real time using a wired / wireless communication network (CID ₁ ) and a first holding vehicle certificate (Cert ₁ ') before the first vehicle transmits a traffic information message (TrafficMsg) to the second one of the plurality of vehicles The second vehicle confirms the identity of the first vehicle and performs an integrity verification on the traffic information message (TrafficMsg) by transmitting the traffic information message (TrafficMsg) to the second vehicle.

The authentication-based message aggregation protocol management system according to the present invention includes a session key based local certificate (SKLC) which is a session key based local certificate and a CMAP (Message Aggregation Protocol) including a MAP (Message Aggregation Protocol) aggregating a traffic information message (Certificate-based Message Aggregation Protocol), it has a first effect of clearly authenticating a traffic information message when transmitting messages between vehicles.

In addition, the present invention utilizes a Certificate-based Message Aggregation Protocol (CMAP) for verifying message integrity by a hash function operation to securely provide highly reliable information, and also improves communication efficiency Gives a second effect.

In addition, the present invention has been devised to overcome the aforementioned weak points in the prior art, and it is an object of the present invention to determine the accuracy of a traffic information message (TrafficMsg) sent from another vehicle so as to respond to or defend against such attacks, Based message aggregation protocol management system, which is designed to check the identity of the vehicle, and to detect and prevent (or defend) the above attacks by accurately checking the identity of the vehicle by mounting a Certificate-based Message Aggregation Protocol (CMAP) 3 gives effect.

1 is a block diagram illustrating an authentication-based message aggregation protocol management system according to an embodiment of the present invention.
2 is a diagram illustrating an authentication-based message aggregation protocol management system according to an embodiment of the present invention.
FIG. 3 is a flow chart illustrating a process of designing a Certificate-based Message Aggregation Protocol (CMAP) applied to an authentication-based message aggregation protocol management system according to an embodiment of the present invention.
4 is a flowchart illustrating a group setting step in an integrity verification process performed through an authentication-based message aggregation protocol management system according to an embodiment of the present invention.
FIG. 5 is a flowchart illustrating a message aggregation process and an integrity verification step of an aggregation message performed after group setting in an authentication-based message aggregation protocol management system according to an embodiment of the present invention.
6 is a flowchart illustrating verification steps for a first vehicle certificate for holding a vehicle 1 configured on an authentication-based message aggregation protocol management system according to an embodiment of the present invention.

[Example]

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

1 is a diagram illustrating an authentication-based message aggregation protocol management system according to an embodiment of the present invention.

Referring to FIG. 1, the authentication-based message aggregation protocol management system 1000 designs a Certificate-based Message Aggregation Protocol (CMAP) that combines a cryptographic base and a grouping base that satisfy both the security and privacy requirements of a VANET, It is a system that does not know the ID of the actual vehicle that sent the message but that enhances the security of the VANET and improves the network efficiency by identifying the group to which the vehicle belongs and verifying the vehicle identification and message integrity. A VANET server 200, first and second vehicles 300 and 400, and a road side unit (RSU) 500.

Here, CMAP is a protocol that uses a group signature and a beneficial signature that can guarantee the anonymity of a vehicle that transmits a traffic information message.

As an example of a CMAP, the GSIS (Group Signature and Identity-based Signature) protocol proposed by X. Lin et al. Is a representative example of a cryptography-based protocol based on group signatures.

Although GSIS has the advantage of not having to send a certificate, a vast amount of computation is required to ensure that the transmitted vehicle is included in the revocation list. The grouping-based protocol is to group vehicles together to hide the exact ID and location of each vehicle. C. Zhang et al.

2, the authentication-based message aggregation protocol management system 1000 according to an exemplary embodiment of the present invention includes a plurality of V2I (Vehicle-to- based message aggregation protocol management system that performs authentication of the first vehicle 300 among a plurality of vehicles 600 using an infrastructure communication network. A more detailed description follows.

First, the roadside repeater 500 intermediates a V2I communication between a plurality of vehicles 600 and a local VANET server 200 by forming a V2I (Vehicle-to-Infrastructure) communication network, 1 public key (PKey ₁ ) to the local VANET server (200).

The local VANET server 200 generates a session key using the EC-DH algorithm with the vehicle in the area, generates a local certificate SKLC using the session key, and authenticates the identity of the vehicle with the SKLC.

To this end, a local VANET server 200 includes a first public key (PKey ₁₎ generating a local session key ((SK _LV) to, and the local session key ((SK _LV) and the mechanism ratio of local certificate (Cert _LV) To generate a first vehicle certificate (Cert ₁ ) for authenticating the identity of the first vehicle (300).

The VANET server 100 controls, monitors, and controls the traffic state and operation state between the roadside repeater 500 and the local VANET server 200 in real time using a wired / wireless communication network.

Also, before the first vehicle 300 transmits a traffic information message (TrafficMsg) possessed by the second vehicle 400 among the plurality of vehicles 600, the first delegation ID (CID ₁ ) and the first vehicle certificate for holding (Cert ₁ ') to the second vehicle 400, the second vehicle 400 confirms the identity of the first vehicle 300 and performs integrity verification of the traffic information message (TrafficMsg) .

The authentication-based message aggregation protocol management system 1000 designs and manages the integrity of a traffic information message (TrafficMsg) by designing a Certificate-based Message Aggregation Protocol (CMAP) as described below. The CMP design process for this is as follows (refer to FIG. 3)

The first vehicle 300 has a first delegation ID (H) which has been concatenated with the first master key (MK ₁ ) and the first unique ID (ID ₁ ) and has been hashed into the hash function (H) CID ₁ ), and then transmits the first delegation ID (CID ₁ ) to the local VANET server 200 (S 100, S 110).

Here, the plurality of vehicles 600 each have a unique ID (ID _V ) and a master key (MK _V ), are registered in the VANET server 100, and are encrypted using a secret key (SKey _V ) _V ), respectively.

When the local VANET server 200 transmits the first delegation ID CID ₁ to the VANET server 100 in step S120 and the first delegation ID CID ₁ is not confirmed in the VANET server 100, (200) transmits the pre-generated connection rejection message to the first vehicle (300) and forcibly terminates the generation of the first vehicle certificate (Cert ₁ ), or the first delegation ID (CID ₁ ) is confirmed in the VANET server , The first vehicle 300 transmits the first public key PKey ₁ to the local VANET server 200 (S130).

The local VANET server 200 calculates the first extracted value extracted by multiplying the first public key PKey ₁ and the apparatus private key SKey _LV as shown in Equation (2) first by creating a local session key (SK _LV) by one modular operation, mechanism non-authenticated valid date (T), local certificate (Cert _LV) a first delegated ID (CID _1), the local session key (SK _LV, with ) Are concatenated and hashed to a hash function H (S140, S150).

Also, the local VANET server 200 obtains a value obtained by multiplying the hash local Hash value (H _LV ) by the local session key (SK _LV ) and a value obtained by multiplying the local certificate (Cert _LV ) by It generates a first vehicle certificate (Cert ₁₎ to a second extraction to extract value from that the add operation by the second modular operation (S160).

The local VANET server 200 stores a first delegation ID (CID ₁ ), a first vehicle certificate (Cert ₁ ) and a certification effective date (T) in its own database and includes a local public key (PKey _LV ) T) and a local certificate (Cert _LV ) to the first vehicle 300 (S170).

The first vehicle 300 can output the third extracted value obtained by the multiplication of the first vehicle secret key SKey ₁ with the local public key PKey _LV as a third modular operation and by concatenating the first session key (SK ₁₎ generate, the first delegated ID (CID _1), local certificate (Cert _LV), the authentication is valid date (T) and the first session key (SK ₁₎ hash function ( H) the extraction of the first hash value (H ₁₎ hash of the following, a first hash value (H ₁₎ and the first session key (SK ₁₎ a multiply operation, and through that the local certificate (Cert _LV) add operation The extracted fourth extracted value is subjected to a fourth modulo operation to generate a retaining first vehicle certificate (Cert ₁ ') (S180, S190).

Here, it is assumed that the first holding vehicle certificate (Cert ₁ ') is the same value as the first vehicle certificate (Cert ₁ ) generated in the local VANET server 200, and if the first vehicle certificate for holding Cert ₁ ') And the first vehicle certificate (Cert ₁ ) are different, the first vehicle 300 is regarded as a hacking vehicle that steals a unique ID (ID _V ).

Then, the authentication-based message aggregation protocol management system 1000 equipped with the Certificate-based Message Aggregation Protocol (CMAP) does not know the ID of the actual vehicle that transmitted the traffic information message, but identifies the group to which the vehicle belongs, Verify message integrity. The group setting phase during the verification is as follows (refer to FIG. 4)

That is, when one of the plurality of vehicles 600 enters the road, one of them broadcasts current position information, current speed information, and current direction information to neighboring vehicles, and newly enters the road among the plurality of vehicles 600 A plurality of vehicles are classified into a temporary group (S100 ', S110', S120 ', S130') after confirming the moving direction information, the traveling speed information, and the road number of each other.

One of which is selected as a group header because it is located at a place to broadcast in units of one hop with a plurality of vehicles included in the temporary group, and the group header includes a holding vehicle certificate (Cert _V ') provided from a plurality of vehicles as a local VANET And requests the server 200 for confirmation (S140 ', S150').

When confirming that the local VANET server 200 matches between the holding vehicle certificate (Cert _V ') and the prepared vehicle certificate (Cert _V ), the group header is assigned to the temporary group so that the group header is included in the temporary group The group number is broadcast to a plurality of vehicles (S160 ', S170', S180 ').

When a plurality of vehicles within a temporary group public key (Pkey _V) and broadcast the group number, in the plurality of vehicles, check the respective group number, and a public key (Pkey _V) and his private key (SKey _V) group key ( GKey _V ), and the temporary group is set to the vehicle group 600 (S190 ').

The message aggregation step S100 'performed after completing the group setting step in the process of performing the verification by the authentication-based message aggregation protocol management system 1000 equipped with the Certificate-based Message Aggregation Protocol (CMAP) is as follows. 5 Reference>

A plurality of vehicles included in the vehicle group 600 transmit the traffic information message (TrafficMsg) to the group header, and the group header confirms the message valid period with the time stamp of the traffic information message (TrafficMsg) (S110 & ).

The group header first verifies the vehicle identity using the holding vehicle certificate (Cert _V ') of the vehicle that has transmitted the traffic information message (TrafficMsg) among the plurality of vehicles, and confirms the traffic information message (TrafficMsg) (S130 ") whether the integrity of the vehicle group 600 and the member belonging to the vehicle group 600 is confirmed.

 Assuming that the first and second confirmations are established, the group header compares traffic information messages (TrafficMsg) collected from a plurality of vehicles to delete duplicate data (S140 ").

The group header transmits an aggregation message (AgrMsg) including a deduplicated traffic information message (TrafficMsg '), an aggregation message generation time, a certificate of a group header, and a sign to the group header of another temporary group (S150 " .

Continuously, the integrity verification steps for the aggregation message (AgrMsg) are as follows.

Another group header that receives the aggregation message AgrMsg from the group header checks whether the aggregation message (AgrMsg) is valid using the time stamp. The other group header identifies the local VANET server 200 to a certificate (Cert _H (S160 ", S170").

When the local VANET server 200 confirms the existence of the certificate (Cert _H ) in the group header, the other group header generates a check signature (chksign) for the aggregation message (AgrMsg) with the second public key (PKey ₂ ) It is confirmed whether or not it is the same as the sign of the post-aggregation message (S180 ").

If the check signature chskign and the sign are matched, the other group header signs the aggregation message AgrMsg with the group key GKey _{V and} sends it to a plurality of vehicles included in another vehicle group (not shown) (S190 ").

Finally, verification of the first holding vehicle certificate (Cert ₁ ') generated from the first vehicle is carried out as described below (S100 "').

The first vehicle 300 has a first delegate ID (CID ₁ ) of the first vehicle 300 and a first vehicle certificate (Cert ₁ ') for holding before transmitting the traffic information message (TrafficMsg) to the second vehicle 400. [ To the second vehicle 400. The second vehicle 400 generates a random number and transmits a first delegation ID CID ₁ received from the first vehicle 300 and a random number to the local VANET server 200 (S110 ", S120 "').

However, if the first delegate ID (CID ₁ ) does not exist in the local VANET server 200 (S130 "'), the local VANET server 200 determines that the first vehicle 300 is an unregistered vehicle, (S140 "').

If the first VID server 200 has a first delegation ID CID _{1 in step} S130 "', the local VANET server 200 receives the first delegation ID CID ₁ from the CRL table, retrieve the vehicle certificate (Cert ₁₎ and ensure the validity (T), and the second vehicle a random number, a local certificate local hash value hash (Cert _LV) a hash function (H) received from the (400) (HN _LV ) And the first vehicle certificate (Cert ₁ ) to the second vehicle 400 (S150 ", S160 "').

The second vehicle 400 checks whether or not the second hash value HN ₂ hashes the random number and the local certificate Cert _LV with the hash function H and the local hash value HN _LV , an error message coincides Hsien first vehicle certificate (Cert ₁₎ and the first vehicle certificate for holding (Cert ₁ ') are compared (S170 "', S180"' ).

The second vehicle 400 has a first vehicle certificate (Cert ₁₎ and the first vehicle certificate for holding (Cert ₁ ') to compare Hsien (S190 "to disagreement with each other"), the first vehicle 300 is a unique ID (ID _V ) (S200 "').

If the first vehicle certificate (Cert ₁ ) and the first vehicle certificate for holding (Cert ₁ ') coincide with each other (S 190 ") when the traffic information message (TrafficMsg) between the first and second vehicles 300 and 400 is transmitted, The second vehicle 400 can prevent the traffic information message (TrafficMsg) from being falsified by the Sybil attack by authenticating the traffic information message (TrafficMsg) (S200 ''), and at the same time, More secure and efficient communication is possible.

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.

1000: Authentication-based message aggregation protocol management system
100: VANET server 200: Local VANET server
300, 400: first and second vehicles 500: road relay
600: Vehicle Group

Claims (17)

1. An authentication-based message aggregation protocol management system for performing authentication of a first vehicle among a plurality of vehicles utilizing a V2I (Vehicle-to-Infrastructure) communication network established between a plurality of vehicles and a local VANET server,
(V2I) communication network and intermediates the V2I communication between the plurality of vehicles and the local VANET server, the first public key (PKey ₁ ) held by the first vehicle is transmitted to the local VANET server Road relay;
Generating a local session key (SK _LV ) with the first public key (PKey ₁ ) and using the local session key (SK _LV ) and a non-authenticated local certificate (Cert _LV ) A local VANET server for generating a first vehicle certificate (Cert ₁ )
And a VANET server for controlling, monitoring, and managing traffic states and operation states between the roadside repeater and the local VANET server in real time using a wired / wireless communication network,
(CID ₁ ) and a first holding vehicle certificate (Cert ₁ ') before the first vehicle transmits a traffic information message (TrafficMsg) held by the second one of the plurality of vehicles to the second vehicle Wherein the second vehicle verifies the identity of the first vehicle and verifies the integrity of the traffic information message (TrafficMsg) upon transmission to the vehicle.
The vehicle according to claim 1,
Unique ID (ID _V) and the master key (MK _V) to be retained and registered in the VANET server, respectively, authentication, characterized in that for generating a secret key (SKey _V) and a public key (PKey _V) respectively based message aggregation protocol Management system.
The vehicle according to claim 1,
A first master key (MK _1), a first unique ID (ID ₁₎ for connecting and to then generate the said first delegation ID (CID ₁₎ hash as a hash function (H), said first delegation ID (CID ₁ ) To the local VANET server. ≪ Desc / Clms Page number 21 >
The method of claim 3,
When the local VANET server transmits the first delegation ID (CID ₁ ) to the VANET server, when the first delegation ID (CID ₁ ) is not confirmed in the VANET server, Rejecting the message to the first vehicle and forcibly terminating the generation of the first vehicle certificate (Cert ₁ )
Wherein the first vehicle transmits the first public key (PKey ₁ ) to the local VANET server when the first delegation ID (CID ₁ ) is verified at the VANET server. system.
5. The local VANET server of claim 4,
A first modular operation is performed on the first extracted value extracted by multiplying the first public key PKey ₁ by a mechanism private key SKey _LV to generate a local session key SK _LV , The hash function H is concatenated with the first delegation ID CID ₁ and the local session key SK _{LV in} conjunction with the mechanism validated validity date T, the local certificate Cert _LV , A second extracted value obtained by adding a value obtained by multiplying the local hash value (H _LV ) by the local session key (SK _LV ) and the local certificate (Cert _LV ) 1 &_lt; / RTI > vehicle certificate (Cert ₁ ).
6. The local VANET server of claim 5,
(CID ₁ ), a first vehicle certificate (Cert ₁ ) and a certification effective date (T) in its own database and stores the local public key (PKey _LV ), the certification effective date (T) (Cert _LV ) to the first vehicle. ≪ Desc / Clms Page number 21 >
The vehicle according to claim 6, wherein the first vehicle comprises:
Generates a first session key (SK ₁ ) by performing a third modular operation of a third extracted value extracted by multiplying the first vehicle secret key (SKey ₁ ) by the local public key (PKey _LV ) The first hash value H ₁ has been extracted by concatenating the delegation ID (CID ₁ ), the local certificate (Cert _LV ), the authentication effective date (T) and the first session key (SK ₁ ) Next, the fourth extraction value obtained by multiplying the first hash value (H ₁ ) by the first session key (SK ₁ ) and adding the local certificate (Cert _LV ) is subjected to a fourth modulo operation To generate a first vehicle certificate (Cert ₁ ') for holding.
8. The method as claimed in claim 7, wherein the holding first vehicle certificate (Cert ₁ '
Wherein the value of the first vehicle certificate (Cert ₁ ) generated by the local VANET server is the same value as the first vehicle certificate (Cert ₁ ) generated by the local VANET server.
2. The method according to claim 1, further comprising:
When one of the plurality of vehicles enters the road, one of the plurality of vehicles broadcasts current position information, current speed information, and current moving direction information to neighboring vehicles, Is classified into a temporary group after confirming the traveling direction information, the traveling speed information, and the road number of each other.
10. The method of claim 9,
Wherein one of the plurality of vehicles is selected as a group header because it is located at a place broadcasting on a one-hop basis with the plurality of vehicles included in the temporary group, and the group header includes a holding vehicle certificate (Cert _V ') To the local VANET server.
11. The method of claim 10,
When confirming that the local VANET server agrees with the holding vehicle certificate (Cert _V ') and the pre-generated vehicle certificate (Cert _V ), the group header is assigned to the temporary group, And broadcasts the group number to the plurality of vehicles included in the authentication-based message aggregation protocol management system.
12. The method of claim 11,
When a plurality of vehicles in the temporary group broadcast the public key (Pkey _V ) and the group number, the plurality of vehicles respectively confirm the group number and transmit the public key (Pkey _V ) and its secret key (SKey _V ) To generate a group key (GKey _V ), and the temporary group is set as a vehicle group.
The method of claim 10, further comprising:
A plurality of vehicles included in the vehicle group transmit the traffic information message (TrafficMsg) to the group header,
The group header checks the validity period of the message with the time stamp of the traffic information message (TrafficMsg)
The group header identifies the vehicle identity first by utilizing a holding vehicle certificate (Cert _V ') of the vehicle that has transmitted the traffic information message (TrafficMsg) among the plurality of vehicles, A second confirmation of the integrity of the message (TrafficMsg) and whether it belongs to the vehicle group,
The group headers compare the traffic information messages (TrafficMsg) collected from the plurality of vehicles to delete duplicate data,
The group header includes an aggregation message (AgrMsg) including a deduplicated traffic information message (TrafficMsg '), an aggregation message generation time, a certificate of the group header, and a signature, to a group header of another temporary group Based message aggregation protocol management system.
14. The method of claim 13, further comprising:
Another group header, which has received the aggregation message (AgrMsg) from the group header, checks whether the aggregation message (AgrMsg) is valid using the time stamp,
The other group header requesting the local VANET server to verify the validity of the certificate (Cert _H ) of the group header,
When the local VANET server confirms existence of the certificate (Cert _H ) of the group header, the other group header generates a check signature (chksign) for the aggregation message (AgrMsg) with the second public key (PKey ₂ ) And confirms whether or not the sign of the aggregation message is the same as the sign of the aggregation message,
When the check signature (chksign) and the sign are matched, the other group header signs the aggregation message (AgrMsg) with a group key (GKey _V ) and broadcasts to a plurality of vehicles included in the other vehicle group Based message aggregation protocol management system.
2. The method of claim 1, wherein validation of the first vehicle certificate for holding (Cert ₁ '
(CID ₁ ) of the first vehicle and the first vehicle identification certificate (Cert ₁ ') to the second vehicle before transmitting the traffic information message (TrafficMsg) to the second vehicle 2 to the vehicle
The second vehicle generates a random number and transmits a first delegation ID (CID ₁ ) received from the first vehicle and the random number to the local VANET server,
The local VANET server retrieves a first vehicle certificate (Cert ₁ ) 1: 1 matched with a first delegation ID (CID ₁ ) in the CRL table and verifies the validity period (T) Delivers the random number, the local hash value (HN _LV ) hash of the local certificate (Cert _LV ) to the hash function (H) and the first vehicle certificate (Cert ₁ ) to the second vehicle,
The second vehicle checks whether the second hash value (HN ₂ ) having the random number and the local certificate (Cert _LV ) is hashed by the hash function (H) and the local hash value (HN _LV ) And compares the first vehicle certificate (Cert ₁ ) with the first vehicle certificate (Cert ₁ ') for retention when a match is found.
16. The method of claim 15,
If the first delegation ID (CID ₁ ) is not present in the local VANET server,
Wherein the local VANET server determines that the first vehicle is an unregistered vehicle and broadcasts a warning message to the plurality of vehicles.
16. The vehicle according to claim 15,
The first vehicle certificate (Cert ₁₎ and holds the first vehicle certificate (Cert ₁ ') specific to the comparison Chien the first vehicle to mismatch each other ID (ID _V) authentication, characterized in that regard as to steal hacking vehicle Based message aggregation protocol management system.

Images