Train-ground communication method and system applied to train control system

Abstract

The invention discloses a train-ground communication method and system applied to a train control system, and the method comprises the steps: firstly, obtaining a second verification message from communication data sent by ground equipment through vehicle-mounted equipment, and obtaining a first verification message from communication data sent by the vehicle-mounted equipment through the ground equipment; and then, the vehicle-mounted equipment and the ground equipment respectively judge whether the vehicle-mounted equipment and the ground equipment support a national secret algorithm or not based on the acquired corresponding verification messages so as to perform different processing on communication data between the vehicle-mounted equipment and the ground equipment. According to the communication method, while the vehicle-mounted equipment and the ground equipment realize a wireless encryption communication function, cross communication between the vehicle-mounted equipment without the national password function and the ground equipment without the national password function and cross communication between the vehicle-mounted equipment with the national password function and the ground equipment with the national password function are supported; the problem that the operation efficiency is reduced due to encryption of existing upgrading software is solved, the train-ground communication efficiency is improved, and the safety and reliability of train operation are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of rail transit, and in particular relates to a vehicle-ground communication method and system applied to a train control system. Background Art

[0002] In recent years, in the field of rail transit, with the innovation of technology, the speed of trains is steadily increasing. The CTCS3 (my country Train Control System Level 3: China High-speed Railway Train Control System) level train control system independently developed by China has been fully promoted. The system can be divided into three parts: on-board equipment that controls train operation, ground equipment that issues information such as train permits, and vehicle-to-ground communication equipment. If the information data transmitted by the communication equipment is not encrypted and the security is weak, the vehicle-to-ground communication security of the existing CTCS-3 train control system needs to be improved. Therefore, in order to improve the safe operation of trains, the encryption processing of the corresponding wireless network data is urgent. In addition, due to the large number of types and quantities of vehicles used in the train control system, it is difficult to upgrade the software of such a large-scale system. There will still be on-board equipment or ground equipment that does not support the national encryption algorithm. Therefore, how to achieve secure wireless encrypted communication between vehicles and the ground is becoming a technical problem that needs to be solved more and more. Summary of the invention

[0003] In view of the above problems, the present invention provides a vehicle-to-ground communication method and system applied to a train control system, which has strong compatibility, high communication efficiency, and is safe and reliable.

[0004] The object of the present invention is to provide a vehicle-ground communication method applied to a train control system, comprising: The on-board device obtains the second verification message from the communication data sent by the ground device, and the ground device obtains the first verification message from the communication data sent by the on-board device; The on-board device and the ground device respectively determine whether each other supports the national encryption algorithm based on the corresponding verification messages obtained, so as to perform different processing on the communication data between the on-board device and the ground device.

[0005] Furthermore, it also includes the communication between the vehicle-mounted equipment and the ground equipment through Protocol for communication, where The first verification message and the second verification message are respectively The AU1 message and the AU2 message in the protocol, wherein the AU1 message and the AU2 message include a security algorithm field, wherein: When the security algorithm field value of the first verification message and the second verification information message is the first value, it indicates that the vehicle-mounted device and the ground device do not support the national encryption algorithm; When the security algorithm field of the first verification message and the second verification information message takes the second value, it indicates that the on-board device and the ground device support the national encryption algorithm.

[0006] Furthermore, the vehicle-mounted device and the ground device respectively determine whether each other supports the national secret algorithm based on the corresponding verification message obtained, so as to perform different processing on the communication data between the vehicle-mounted device and the ground device, including if it is determined that both support the national secret algorithm, specifically including: The vehicle-mounted device fills the communication data sent except the first verification message into an integer multiple of 16 bytes, and then performs national secret encryption; and, The vehicle-mounted device modifies the security algorithm field of the obtained second verification message to the first value, and obtains 3DES verification data; The communication data except the second verification message in the received non-3DES key data is decrypted with national secret, and then the padding bytes are removed.

[0007] Furthermore, if both support the national encryption algorithm, it also includes, The ground equipment fills the communication data sent except the second verification message to an integer multiple of 16 bytes, and then performs national secret encryption; and, The ground device modifies the security algorithm field of the acquired first verification message to the first value and restores it to 3DES data; The received communication data except the first verification message is decrypted with national secret, and then the padding bytes are removed.

[0008] Furthermore, the vehicle-mounted device and the ground device respectively determine whether each other supports the national secret algorithm based on the corresponding verification message obtained, so as to perform different processing on the data communicated between the vehicle-mounted device and the ground device, and also include if it is determined that neither of them supports the national secret algorithm, specifically including: The vehicle-mounted equipment does not encrypt the communication data sent, and does not decrypt the communication data received; The ground equipment processes the received and sent communication data according to the preset algorithm logic.

[0009] Furthermore, the vehicle-mounted device and the ground device respectively determine whether each other supports the national secret algorithm based on the corresponding verification message obtained, so as to perform different processing on the data communicated between the vehicle-mounted device and the ground device. It also includes if it is determined that the vehicle-mounted device supports the national secret algorithm, and the ground device does not support the national secret algorithm, specifically including: The vehicle-mounted equipment does not encrypt the communication data sent, and does not decrypt the communication data received; The ground device modifies the security algorithm field of the acquired first verification message to the first value and restores it to 3DES data; Processing the received communication data except the first verification message according to a preset algorithm logic; and, The ground equipment processes the sent communication data according to the preset algorithm logic.

[0010] Furthermore, the vehicle-mounted device and the ground device respectively determine whether each other supports the national secret algorithm based on the corresponding verification message obtained, so as to perform different processing on the data communicated between the vehicle-mounted device and the ground device, and also include if it is determined that the vehicle-mounted device does not support the national secret algorithm, and the ground device supports the national secret algorithm, specifically including: The vehicle-mounted equipment does not encrypt the communication data sent, and does not decrypt the communication data received; The ground equipment processes the received and sent communication data according to the preset algorithm logic.

[0011] Furthermore, the first verification message and the second verification message are both transmitted in plain text.

[0012] Furthermore, if the communication data transmitted inside the vehicle-mounted device is a 3DES key, the vehicle-mounted device directly receives it.

[0013] Furthermore, the vehicle-mounted device internally adopts a preset transmission protocol to transmit data, and the preset transmission protocol includes Link Protocol and Serial_Link transmission protocol.

[0014] The present invention also aims to provide a vehicle-to-ground communication system applied to a train control system, comprising a vehicle-mounted device and a ground device, wherein the vehicle-mounted device comprises a vehicle-mounted safety communication unit, and the ground device comprises a communication network, wherein an encryption management module is also provided in the communication network, wherein: The vehicle-mounted security communication unit is used to obtain a second verification message from the communication data sent by the ground device, and to determine whether the ground device supports the national encryption algorithm based on the obtained second verification message, so as to perform different processing on the data communicated between the vehicle-mounted device and the ground device; The encryption management module is used to obtain a first verification message from the communication data sent by the vehicle-mounted device, and to determine whether the vehicle-mounted device supports the national encryption algorithm based on the obtained second verification message, so as to perform different processing on the data communicated between the vehicle-mounted device and the ground device.

[0015] Furthermore, the ground equipment also includes a secure communication server, which is connected to the encryption management module through a switch, and is used to encrypt the communication data padded with an integer multiple of 16 bytes sent by the received communication network except the second verification message when both the vehicle-mounted equipment and the ground equipment support the national encryption algorithm; and to decrypt the communication data sent by the received vehicle-mounted equipment except the first verification message.

[0016] Furthermore, the vehicle-mounted equipment and the ground equipment are connected through Protocol for communication, where The first verification message and the second verification message are respectively The AU1 message and AU2 message in the protocol are transmitted in plain text, and the AU1 message and AU2 message include a security algorithm field, wherein: When the security algorithm field value of the first verification message and the second verification information message is the first value, it indicates that the vehicle-mounted device and the ground device do not support the national encryption algorithm; When the security algorithm field of the first verification message and the second verification information message takes the second value, it indicates that the on-board device and the ground device support the national encryption algorithm.

[0017] Furthermore, the vehicle-mounted device also includes a main control unit, a communication control unit, a communication encryption unit and a radio station, wherein the vehicle-mounted safety communication unit is arranged between the communication control unit and the communication encryption unit, and exchanges communication data with the communication control unit and the communication encryption unit according to the Link Protocol and Serial_Link transmission protocols respectively.

[0018] Furthermore, the ground equipment also includes a radio block center, and the radio block center is connected to the communication network.

[0019] The communication method of the present invention realizes the function of wireless encrypted communication between the train and the ground, and supports communication in which one party is an encrypted device and the other party is a non-encrypted device, that is, it supports cross-communication between vehicle-mounted devices without national security functions and vehicle-mounted devices with national security functions and ground-based devices without national security functions and ground-based devices with national security functions respectively, reduces the problem of reduced operational efficiency caused by existing upgraded software encryption, improves the efficiency of vehicle-ground communication, and improves the safety and reliability of train operation.

[0020] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1A schematic flow chart of a vehicle-to-ground communication method applied to a train control system in an embodiment of the present invention is shown; Figure 2 An embodiment of the present invention is shown Schematic diagram of the protocol interaction process; Figure 3 A schematic diagram of the structure of a vehicle-to-ground communication system applied to a train control system in an embodiment of the present invention is shown; Figure 4 A schematic diagram of the structure of a vehicle-mounted device in an embodiment of the present invention is shown; Figure 5 A schematic structural diagram of a ground device in an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] like Figure 1 As shown, an embodiment of the present invention introduces a vehicle-to-ground communication method applied to a train control system, which realizes the function of wireless encrypted communication between the vehicle and the ground, and supports communication in which one party is an encrypted device and the other party is a non-encrypted device. The method includes, first, the vehicle-mounted device obtains a second verification message from the communication data sent by the ground device, and the ground device obtains a first verification message from the communication data sent by the vehicle-mounted device; then, the vehicle-mounted device and the ground device respectively judge whether each other supports the national encryption algorithm based on the corresponding verification messages obtained, so as to perform different processing on the communication data between the vehicle-mounted device and the ground device. The above method realizes wireless encrypted communication between the vehicle and the ground, and is compatible with supporting cross-communication between vehicle-mounted devices without national encryption functions and vehicle-mounted devices with national encryption functions and ground devices without national encryption functions and ground devices with national encryption functions, respectively, reducing the problem of reduced operating efficiency caused by the existing upgraded software encryption, improving the vehicle-to-ground communication efficiency, and improving the safety and reliability of train operation.

[0025] In the embodiment of the present invention, the vehicle-mounted device and the ground device are connected via Protocol for communication, such as Figure 2 As shown, The interaction process of the protocol, when establishing a secure connection between the safety layers, when the Sa-CONNECT.request primitive requests a secure connection, the safety layer will request the establishment of a transport connection through the TCONN.req service primitive. This service primitive includes the first message (AU1 SaPDU) of the peer entity authentication process as user data; among them, SaPDU (Session Activation Packet Data Unit) refers to the session activation packet unit, and SaPDU is a packet unit used to activate the session during the communication process. If the receiver accepts this request and has informed the corresponding user of the secure establishment of the connection through TCONN.ind, it will then respond to the TC (Transport Connection) establishment request through the T-CONN.resp service primitive, which includes the second message (AU2 SaPDU) of the peer entity authentication protocol as user data. After the transport connection is successfully established, the calling transport entity will use the TCONN.conf service primitive to notify the security layer and forward the AU2 SaPDU as user data to the security layer. The security entity then generates an AU3 SaPDU containing the third message of the authentication protocol and forwards this message to the transport layer using the T-DATA.request service primitive. The receiving transport entity forwards the AU3 SaPDU as user data to the security layer using the T-DATA.ind service primitive, and the security entity evaluates the AU3 SaPDU. If the AU3 SaPDU evaluation is successful, the security entity forwards the Sa-CONN.ind service primitive to the security user, and if the security user accepts the security connection establishment request, it responds using the Sa-CONN.resp service primitive. The security entity verifies the response and generates an AR SaPDU containing the third message of the authentication protocol and forwards this message to the security layer using the T-DATA.req service primitive. The receiving transport entity forwards the AR SaPDU as user data to the security layer using the T-DATA.ind service primitive, and after the transport connection is successfully established, the calling transport entity notifies the security layer using the TCONN.conf service primitive.

[0026] In the embodiment of the present invention, in the above The national encryption and decryption functions are added based on the AU1, AU2, AU3, AR, DT, DI and other messages (i.e. communication data) specified in the protocol, including: The message is padded to an integer multiple of 16 bytes before encryption. The corresponding decryption and removal of padding bytes also follow the following rules. First, the padding bytes are located at Before the message code stream (corresponding communication data), secondly, the first padding byte is shown in Table 1. Table 1 The first padding byte of the message

[0027] The values ​​of the remaining padding bytes except the first padding byte are 0.

[0028] Furthermore, bit1 to bit5 represent the number of padding bytes, where: The relationship between the remainder of the message length divided by 16 and the padding byte data is shown in Table 2. Table 2 Relationship between the remainder of the message length divided by 16 and the padding byte data

[0029] By modifying the existing The protocol supports the scenarios where on-board devices with / without national security functions and ground devices with / without national security functions communicate simultaneously. This method has strong applicability and improves the reliability of vehicle-ground communication.

[0030] In the embodiment of the present invention, the first verification message and the second verification message are respectively The AU1 message and AU2 message in the protocol include a security algorithm field indicating whether the national encryption algorithm is supported, wherein the security algorithm field in the first verification message and the second verification message takes a first value, indicating that the vehicle-mounted device and the ground device do not support the national encryption algorithm; the security algorithm field in the first verification message and the second verification message takes a second value, indicating that the vehicle-mounted device and the ground device support the national encryption algorithm. Preferably, the first value is 1 and the second value is 2. Exemplarily, the values ​​of the SaF field in the AU1 message content and the AU2 message content shown in Tables 3 and 4 are both 1, that is, the vehicle-mounted device and the ground device do not support the national encryption algorithm.

[0031] Table 3 AU1 message content

[0032] Among them, the ETY: field is used to identify the ETCS (European Train Control System) ID type, involving SA (Security Authority), RBC (Radio Block Center) engine, Balise (a trackside device), and entities related to key management and interlocking. MTI: Message type identifier, here is AU1, indicating that this is an AU1 type message. DF: Direction flag, '0' indicates that the message is sent to the responder. SA: ETCS ID of the caller, occupying 2 to 4 octets. SaF: Security algorithm field, used in the embodiment of the present invention to indicate whether the national encryption algorithm is supported. Here it is specified as a single DES (Data Encryption Standard) using the modified MAC algorithm 3. All other values ​​are reserved. Ra: The random number Ra of the first authentication message, occupying 6 to 13 octets.

[0033] Table 4 AU2 message content

[0034] ETY: The field is used to identify the ETCS (European Train Control System) ID type, involving SA (Security Authority), radio fill unit, engine, RBC (RadioBlock Center), Balise (a trackside device), and entities related to key management and interlocking. MTI: Message type identifier, here is AU2, indicating that this is an AU2 type message. DF: Direction flag, '1' indicates that the message is sent to the initiator. SA: ETCS ID of the responder, occupying 2 to 4 octets. SaF is used to indicate whether the national encryption algorithm is supported. Here it is specified as single DES (Data Encryption Standard) using modified MAC algorithm 3. All other values ​​are reserved. R A : The random number R of the second authentication message, which occupies 6 to 13 octets. MAC (Message Authentication Code) field: The message authentication code field, which occupies 14 to 21 octets, is calculated according to the rules of the peer entity and message source authentication procedure.

[0035] In an embodiment of the present invention, the on-board device and the ground device respectively determine whether each other supports the national encryption algorithm based on the corresponding verification messages obtained, including the on-board device determining whether the ground device supports the national encryption algorithm based on the second verification message obtained, and the ground device determining whether the on-board device supports the national encryption algorithm based on the first verification message obtained.

[0036] Specifically, the vehicle-mounted device determines whether the ground device supports the national encryption algorithm based on the obtained second verification message, including making a judgment before sending the communication data to the ground device and when receiving the communication data sent by the ground device, and then performing different processing on the communication data based on the judgment result. In addition, the vehicle-mounted device uses a preset transmission protocol to forward data, and the preset transmission protocol includes Link Protocol and Serial_Link transmission protocol. Further, before sending the communication data to the ground device, the vehicle-mounted device determines whether the ground device supports the national encryption algorithm based on the second verification message and performs different processing on the communication data between the vehicle-mounted device and the ground device based on the judgment result, including the following processing process: First, the data to be sent to the ground equipment is obtained based on the Link Protocol and Serial_Link transmission protocol.

[0037] Secondly, the AU1 message (first verification message) is not encrypted with the national secret code, and no padding bytes are added, so it is transmitted in plain text. If the vehicle-mounted device supports the national secret code algorithm, the SaF field (security algorithm field) of the AU1 message is changed from 1 to 2 to indicate support for the national secret code algorithm.

[0038] Then, the AU2 message (second verification message) sent by the acquired ground device is analyzed. If the SaF field of the AU2 message is 1, the ground device does not support the national encryption algorithm, and the data sent to the ground device is not encrypted with the national encryption. Then, the new data is obtained according to the Link Protocol and Serial_Link transmission protocol and sent to the ground device. If the SaF field of the AU2 message is 2, the ground device supports the national encryption algorithm, and padding data is added to the data except the AU1 message, and then the national encryption is performed. After the encrypted data is obtained, the new data is obtained according to the Link Protocol and Serial_Link transmission protocol, and then sent to the ground device.

[0039] Furthermore, before receiving the communication data from the ground device, the vehicle-mounted device determines whether the ground device supports the national encryption algorithm and performs different processing on the communication data between the vehicle-mounted device and the ground device according to the judgment result, including the following processing process: Determine whether the communication data is 3DES key data. Preferably, the 3DES key data is data for internal communication of the vehicle-mounted device, not communication data between the vehicle-mounted device and the ground device.

[0040] If it is 3DES key data, it is directly received; if it is non-3DES key data, the following processing is included: First, the data sent by the ground equipment is obtained according to the Link Protocol and Serial_Link transmission protocol; Then, the second verification message sent by the ground device is obtained. If the SaF field of the AU2 message is 1, it means that the ground device does not support the national encryption algorithm. In the future, the data received from the ground device will not be decrypted by the national encryption algorithm and will be directly received.

[0041] If the SaF field of the AU2 message is 2, it means that the ground equipment supports the national encryption algorithm. First, change the SaF field of the AU2 message from 2 to 1, obtain only 3DES check data, and then receive new data according to the Link Protocol and Serial_Link transmission protocols. In addition, for data other than the AU2 message, perform national encryption decryption, delete the padding data, and finally receive new data according to the Link Protocol and Serial_Link transmission protocols.

[0042] Further, the ground device determines whether the vehicle-mounted device supports the national encryption algorithm based on the acquired AU1 message, including making a judgment before sending communication data to the vehicle-mounted device and when receiving communication data sent by the vehicle-mounted device, and then performing different processing on the communication data based on the judgment result. Further, the ground device includes ground devices that do not support the national encryption algorithm and ground devices that support the national encryption algorithm.

[0043] When the ground device does not support the national encryption algorithm, the ground device determines whether the vehicle-mounted device supports the national encryption algorithm before sending the communication data to the vehicle-mounted device and performs different processing on the communication data between the vehicle-mounted device and the ground device according to the judgment result, including the following processing procedures: The AU1 message sent by the on-board device is transmitted in plain text, and the SaF field of the message is 1, indicating that the on-board device does not support the national encryption algorithm. The ground device will process the communication data received from the on-board device according to the preset algorithm logic and send it to the wireless block center (RBC) in the ground device, and will also process the received RBC data according to the preset algorithm logic and send it to the on-board device; among which, the preset algorithm logic processing includes but is not limited to processing through the 3DES (Triple Data Encryption Standard) algorithm (a symmetric encryption algorithm).

[0044] The AU1 message sent by the on-board device is transmitted in plain text, and the SaF field of its message is 2, which means that the on-board device supports the national encryption algorithm. The ground device changes the SaF field of the AU1 message message from 2 to 1, restores it to 3DES data and sends it to the RBC in the ground device. The RBC host then believes that the data received from the on-board device is 3DES verification data.

[0045] The ground device does not modify the AU2 message sent by the RBC, maintains the SaF field of the AU2 message as 1, indicating 3DES data, and then sends it to the vehicle device. After that, the remaining messages sent by the RBC in the ground device are processed according to the preset 3DES data method. At the same time, the vehicle device does not perform national secret encryption when sending data. Furthermore, the preset 3DES data method is the 3DES algorithm.

[0046] In the embodiment of the present invention, when the ground device supports the national encryption algorithm, the ground device determines whether the vehicle-mounted device supports the national encryption algorithm before sending the communication data to the vehicle-mounted device and performs different processing on the communication data between the vehicle-mounted device and the ground device according to the judgment result, including the following processing process: The AU1 message sent by the on-board device is transmitted in plain text, and the SaF field of the message is 1, indicating that the on-board device does not support the national encryption algorithm. The ground device will process the communication data received from the on-board device according to the preset algorithm logic and send it to the radio block center (RBC) in the ground device, and will also process the received RBC data according to the preset algorithm logic and send it to the on-board device.

[0047] The AU1 message sent by the vehicle-mounted device is transmitted in plain text. The SaF field of the message is 2, indicating that the vehicle-mounted device supports the national encryption algorithm. It is processed in the following order: First, the ground device changes the SaF field of the AU1 message from 2 to 1, restores it to 3DES data and sends it to the RBC in the ground device. The RBC host then considers that the data received from the on-board device is 3DES verification data.

[0048] Then, the ground device changes the SaF field of the AU2 message received from RBC from 1 to 2, indicating support for the national encryption algorithm. Among them, no padding data is added to the AU2 message, and no national encryption is performed, and it is sent directly to the on-board device.

[0049] Finally, for data other than AU1 and AU2 messages, do the following processing: The ground equipment decrypts the data received from the on-board equipment with national secret code, removes the padding data, and then sends it to the RBC host.

[0050] The ground equipment adds padding data to the data sent by the received RBC, encrypts it with national secret code, and then sends it to the on-board equipment.

[0051] In the above method, when at least one of the on-board device and the ground device does not support the national secret algorithm, the on-board device and the ground device do not perform national secret encryption and decryption on the corresponding data, and execute according to the preset algorithm logic. The preset algorithm logic can be processed according to the existing 3DES data method, but is not limited to this. Other data processing methods are applicable to the present invention. In addition, the national secret algorithm includes but is not limited to SM1, SM2, SM3, SM4, SM7, SM9 algorithms, etc.

[0052] The above method supports cross-communication between on-board equipment without national security functions and on-board equipment with national security functions and ground equipment without national security functions and ground equipment with national security functions respectively, and adopts different data encryption processing methods for different situations to improve the efficiency of vehicle-ground communication and improve the safety and reliability of train operation.

[0053] like Figure 3 As shown, an embodiment of the present invention introduces a vehicle-to-ground communication system applied to a train control system that can execute the above method, wherein the system includes a vehicle-mounted device and a ground device, the vehicle-mounted device includes a vehicle-mounted safety communication unit, the ground device includes a communication network, and an encryption management module is also provided in the communication network, wherein the vehicle-mounted safety communication unit is used to obtain a second verification message from the communication data sent by the ground device, and to determine whether the ground device supports the national encryption algorithm based on the obtained second verification message, so as to perform different processing on the data communicated between the vehicle-mounted device and the ground device; the encryption management module is used to obtain a first verification message from the communication data sent by the vehicle-mounted device, and to determine whether the vehicle-mounted device supports the national encryption algorithm based on the obtained second verification message, so as to perform different processing on the data communicated between the vehicle-mounted device and the ground device.

[0054] In an embodiment of the present invention, the ground device further includes a secure communication server, which is connected to the encryption management module via a switch, and is used to perform national encryption on the communication data padded with an integer multiple of 16 bytes except the second verification message sent by the received communication network when both the vehicle-mounted device and the ground device support the national encryption algorithm; and perform national encryption on the communication data except the first verification message sent by the received vehicle-mounted device. The secure communication server is a ground secure communication server.

[0055] In the embodiment of the present invention, the vehicle-mounted device and the ground device are connected via Protocol for communication, where The first verification message and the second verification message are respectively The AU1 message and AU2 message in the protocol are transmitted in plain text, and the AU1 message and AU2 message include a security algorithm field, wherein: When the security algorithm field value of the first verification message and the second verification information message is the first value, it indicates that the vehicle-mounted device and the ground device do not support the national encryption algorithm; When the security algorithm field of the first verification message and the second verification information message takes the second value, it indicates that the on-board device and the ground device support the national encryption algorithm.

[0056] like Figure 4 As shown, the vehicle-mounted equipment also includes a main control unit, a communication control unit (STUV-V unit), a communication encryption unit (STUV-N unit) and a radio station, wherein the vehicle-mounted safety communication unit is arranged between the communication control unit and the communication encryption unit, connected via TCP / IP (Transmission Control Protocol / Internet Protocol), and communicates data with the communication control unit and the communication encryption unit in accordance with the Link Protocol and Serial_Link transmission protocols respectively. Both Link Protocol and Serial_Link transmission protocols are application layer protocols.

[0057] Furthermore, the main control unit is a C3 main control unit, and is connected to the STUV-V unit through an MVB (Multifunction Vehicle Bus). The C3 main control unit is the main logic processing unit of the on-board equipment and is used for train control. The STUV-V unit (the Vital unit of the STU-V device, i.e., the communication control unit) is responsible for processing key-related functions, and the STUV-N (the Non-Vital unit of the STU-V device, i.e., the communication encryption unit) unit is responsible for the communication function with the radio. The STUV-N module is connected to the MT radio through a serial port, and the MT radio (Motive Power Transceiver Radio: locomotive standard radio station) receives and sends vehicle-ground data. Furthermore, the STUV-V unit and the STUV-N unit are generally used for wired data encryption. An on-board safety communication unit is added to the on-board equipment side, so that the on-board safety communication unit processes the data sent from the STUV_V unit to the STUV-N unit in the following order: ①According to Link Protocol and Serial_Link transmission protocol, obtain the encrypted data (i.e. the data sent by STUV_V unit); ② The AU1 message is not encrypted with the national secret code, and no padding bytes are added, so it is transmitted in plain text. If the vehicle-mounted device supports the national secret code algorithm, the SaF field of the AU1 message is changed from 1 to 2 to indicate support for the national secret code algorithm.

[0058] ③According to the analysis of the AU2 message sent by RBC, if the SaF field of the AU2 message is 1, RBC does not support the national encryption algorithm, the data sent to RBC will no longer be encrypted by the national encryption, and only the data sent by the STUV-V unit will be sent to the STUV-N unit according to the LinkProtocol and Serial_Link transmission protocols, and the subsequent steps will not be executed. If RBC supports the national encryption, execute ④.

[0059] ④ For the data to be encrypted with national secret codes, in addition to the AU1 message, add padding data and obtain the data encrypted with national secret codes through the on-board security communication unit.

[0060] ⑤ The encrypted data is sent to the STUV-N unit according to the Link Protocol and Serial_Link transmission protocol to obtain new data.

[0061] Furthermore, the vehicle safety communication unit processes the data sent by the STUV-N unit to the STUV_V unit as follows: 1) The 3DES key received from STUV_N is forwarded to the STUV-V unit, where the 3DES key data is the internal communication data between the STUV-N unit and the STUV_V unit, not the communication data between the ATP and the RBC.

[0062] 2) For non-3DES key data, the following processing is performed in sequence: ①According to Link Protocol and Serial_Link transmission protocol, obtain the data sent by RBC; ② After receiving the AU2 message sent by RBC, if the SaF field of the AU2 message is 1, it means that RBC does not support the national encryption algorithm. Then the data sent by RBC will not be decrypted by the national encryption algorithm, and will be directly forwarded to the STUV-V unit without executing the subsequent steps.

[0063] ③ Receive the AU2 message sent by RBC. If the SaF field of the AU2 message is 2, it means that RBC supports the national encryption algorithm. After changing the SaF field value of the AU2 message from 2 to 1, obtain data including only 3DES checksum, and obtain new data according to the Link Protocol and Serial_Link transmission protocol and send it to the STUV-V unit.

[0064] For communication data other than AU2, the decrypted data is obtained after being decrypted by the national secret code of the on-board safety communication unit, the padding data is deleted, and then the new data is obtained according to the Link Protocol and Serial_Link transmission protocol and sent to the STUV-N unit.

[0065] In the embodiment of the present invention, the preset protocol data of the vehicle-mounted device and the ground device is 3DES data, and the national encryption algorithm is a layer of packaging based on the 3DES algorithm.

[0066] like Figure 5 As shown, the ground equipment also includes a radio block center, which is connected to the communication network through a switch. Preferably, the communication equipment also includes multiple communication networks. Further, the communication network is an ISDN (Integrated Services Digital Network), wherein the ISDN includes an ISDN that supports the national encryption algorithm and an ISDN that does not support the national encryption algorithm. Among them, the ISDN that does not support the national encryption algorithm performs the following steps: The AU1 message sent by ATP (i.e., the on-board device) is transmitted in plain text. If the SaF field of its message is 1, it means that ATP does not support national encryption. In this case, ISDN will process the received ATP data (data sent by the on-board device) according to the preset algorithm logic of the ISDN server software and send it to RBC, and will process the received RBC data according to the preset algorithm logic and send it to ATP.

[0067] The AU1 message sent by ATP is transmitted in plain text. If the SaF field of the message is 2, it means that ATP supports national encryption. Then ISDN changes the SaF field of the AU1 message from 2 to 1, obtains 3DES data and sends it to RBC. Then the RBC host considers the received ATP data as 3DES verification data. ISDN does not modify the AU2 sent by RBC, but keeps the SaF field of the AU2 message as 1, indicating 3DES data, and sends it to ATP. After that, the rest of the communication messages are processed by ISDN according to the existing 3DES data mode (3DES algorithm) (It should be noted that when ISDN does not support the national encryption algorithm, the communication data sent by ATP is also not encrypted with the national encryption).

[0068] ISDN that supports the national encryption algorithm performs the following steps: The AU1 message sent by ATP is transmitted in plain text. If the SaF field of the message is 1, it means that ATP does not support national encryption. Then ISDN will process the received ATP data according to the preset algorithm logic and send it to RBC, and will process the received RBC data according to the preset algorithm logic and send it to ATP. The preset algorithm logic processing includes but is not limited to the 3DES algorithm.

[0069] The AU1 message sent by ATP is transmitted in plain text, and the SaF field of the message is 2, indicating that ATP supports national encryption and is processed in the following order.

[0070] ① For AU1 message, ISDN changes the SaF field of AU1 message from 2 to 1, restores it to 3DES data and sends it to RBC. Then the RBC host considers the received ATP data as 3DES verification data.

[0071] ② After receiving the AU2 message from RBC, the SaF field of the AU2 message message is changed from 1 to 2 to indicate support for the national encryption algorithm message. No padding data is added, no national encryption is performed, and it is sent directly to ATP.

[0072] ③ For other messages (communication data) except AU1 and AU2, do the following processing: The data sent by ATP to RBC is sent by ISDN to the ground security communication server according to the communication protocol. After receiving the data after national security decryption (that is, the ground security communication server decrypts the data with national security), the padding data is removed and sent to the RBC host according to the protocol between the RBC host and the ISDN server.

[0073] The data sent by RBC to ATP, after ISDN adds padding data, is sent to the ground security communication server according to the communication protocol, and then receives the national secret encrypted data (that is, the ground security communication server encrypts the data with national secret), and then sends it to ATP according to the original processing method (wireless communication method).

[0074] In the above system, an on-board security communication unit is added to the on-board equipment, a security communication server and an encryption and decryption module set in the ISDN are added to the ground equipment, so that encryption and decryption are performed by relying on hardware equipment, and the limitation of relying on software encryption is broken away. Thus, while the on-board equipment and the ground equipment realize the wireless encrypted communication function, it also supports cross-communication between on-board equipment without national security function and on-board equipment with national security function and ground equipment without national security function and ground equipment with national security function respectively, which greatly improves the security of data.

[0075] Furthermore, external encryption equipment is added to perform encryption and decryption through hardware. Without modifying the on-board software and with minimal modification of the ground software, it supports communication between the encryption vehicle and encrypted ground equipment, and between the encryption vehicle and non-encrypted ground equipment, thus upgrading equipment while ensuring operational efficiency to the greatest extent possible.

[0076] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein; and these modifications or substitutions do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A vehicle-to-ground communication method applied to a train control system, characterized in that: include, The on-board device obtains the second verification message from the communication data sent by the ground device, and the ground device obtains the first verification message from the communication data sent by the on-board device; The on-board device and the ground device respectively determine whether each other supports the national encryption algorithm based on the corresponding verification messages obtained, so as to perform different processing on the communication data between the on-board device and the ground device.

2. The vehicle-to-ground communication method applied to a train control system according to claim 1, characterized in that: It also includes the communication between the vehicle-mounted equipment and the ground equipment Protocol for communication, where The first verification message and the second verification message are respectively The AU1 message and the AU2 message in the protocol, wherein the AU1 message and the AU2 message include a security algorithm field, wherein: When the security algorithm field value of the first verification message and the second verification information message is the first value, it indicates that the vehicle-mounted device and the ground device do not support the national encryption algorithm; When the security algorithm field of the first verification message and the second verification information message takes the second value, it indicates that the on-board device and the ground device support the national encryption algorithm.

3. The vehicle-to-ground communication method applied to a train control system according to claim 2, characterized in that: The vehicle-mounted device and the ground device respectively determine whether each other supports the national secret algorithm based on the corresponding verification message obtained, so as to perform different processing on the communication data between the vehicle-mounted device and the ground device, including if it is determined that both support the national secret algorithm, specifically including: The vehicle-mounted device fills the communication data sent except the first verification message into an integer multiple of 16 bytes, and then performs national secret encryption; and, The vehicle-mounted device modifies the security algorithm field of the obtained second verification message to the first value, and obtains 3DES verification data; The communication data except the second verification message in the received non-3DES key data is decrypted with national secret, and then the padding bytes are removed.

4. The vehicle-to-ground communication method applied to a train control system according to claim 2, characterized in that: If both support the national secret algorithm, it also includes: The ground equipment fills the communication data sent except the second verification message to an integer multiple of 16 bytes, and then performs national secret encryption; and, The ground device modifies the security algorithm field of the acquired first verification message to the first value and restores it to 3DES data; The received communication data except the first verification message is decrypted with national secret, and then the padding bytes are removed.

5. The vehicle-to-ground communication method applied to a train control system according to claim 2, characterized in that: The vehicle-mounted device and the ground device respectively determine whether each other supports the national secret algorithm based on the corresponding verification messages obtained, so as to perform different processing on the data communicated between the vehicle-mounted device and the ground device, and also include if it is determined that neither of them supports the national secret algorithm, specifically including: The vehicle-mounted equipment does not encrypt the communication data sent, and does not decrypt the communication data received; The ground equipment processes the received and sent communication data according to the preset algorithm logic.

6. The vehicle-to-ground communication method applied to a train control system according to claim 2, characterized in that: The on-board device and the ground device respectively determine whether each other supports the national secret algorithm based on the corresponding verification messages obtained, so as to perform different processing on the data communicated between the on-board device and the ground device. It also includes if it is determined that the on-board device supports the national secret algorithm, but the ground device does not support the national secret algorithm, specifically including: The vehicle-mounted equipment does not encrypt the communication data sent, and does not decrypt the communication data received; The ground device modifies the security algorithm field of the acquired first verification message to the first value and restores it to 3DES data; Processing the received communication data except the first verification message according to a preset algorithm logic; as well as, The ground equipment processes the sent communication data according to the preset algorithm logic.

7. The vehicle-to-ground communication method applied to a train control system according to claim 2, characterized in that: The on-board device and the ground device respectively determine whether each other supports the national secret algorithm based on the corresponding verification message obtained, so as to perform different processing on the data communicated between the on-board device and the ground device. It also includes if it is determined that the on-board device does not support the national secret algorithm, and the ground device supports the national secret algorithm, specifically including: The vehicle-mounted equipment does not encrypt the communication data sent, and does not decrypt the communication data received; The ground equipment processes the received and sent communication data according to the preset algorithm logic.

8. The vehicle-to-ground communication method applied to a train control system according to any one of claims 1 to 5, characterized in that: The first verification message and the second verification message are both transmitted in plain text.

9. The vehicle-to-ground communication method applied to a train control system according to claim 8, characterized in that: It also includes that if the communication data transmitted inside the vehicle-mounted device is a 3DES key, the vehicle-mounted device directly receives it.

10. The vehicle-to-ground communication method applied to a train control system according to claim 9, characterized in that: The vehicle-mounted device internally adopts a preset transmission protocol to transmit data, and the preset transmission protocol includes Link Protocol and Serial_Link transmission protocol.

11. A vehicle-to-ground communication system applied to a train control system, characterized in that: It includes vehicle-mounted equipment and ground equipment. The vehicle-mounted equipment includes a vehicle-mounted safety communication unit. The ground equipment includes a communication network. The communication network is also provided with an encryption management module. The vehicle-mounted security communication unit is used to obtain a second verification message from the communication data sent by the ground device, and to determine whether the ground device supports the national encryption algorithm based on the obtained second verification message, so as to perform different processing on the data communicated between the vehicle-mounted device and the ground device; The encryption management module is used to obtain a first verification message from the communication data sent by the vehicle-mounted device, and to determine whether the vehicle-mounted device supports the national encryption algorithm based on the obtained second verification message, so as to perform different processing on the data communicated between the vehicle-mounted device and the ground device.

12. The vehicle-to-ground communication system applied to a train control system according to claim 11, characterized in that: The ground equipment also includes a secure communication server, which is connected to the encryption management module through a switch and is used to perform national encryption on the communication data padded with an integer multiple of 16 bytes received from the communication network except for the second verification message when both the vehicle-mounted equipment and the ground equipment support the national encryption algorithm; and to perform national encryption on the communication data received from the vehicle-mounted equipment except for the first verification message.

13. The vehicle-to-ground communication system applied to a train control system according to claim 12, characterized in that: The vehicle-mounted equipment and the ground equipment are connected through Protocol for communication, where The first verification message and the second verification message are respectively The AU1 message and AU2 message in the protocol are transmitted in plain text, and the AU1 message and AU2 message include a security algorithm field, wherein: When the security algorithm field value of the first verification message and the second verification information message is the first value, it indicates that the vehicle-mounted device and the ground device do not support the national encryption algorithm; When the security algorithm field of the first verification message and the second verification information message takes the second value, it indicates that the on-board device and the ground device support the national encryption algorithm.

14. The vehicle-to-ground communication system applied to a train control system according to claim 13, characterized in that: The vehicle-mounted device also includes a main control unit, a communication control unit, a communication encryption unit and a radio station, wherein the vehicle-mounted safety communication unit is arranged between the communication control unit and the communication encryption unit, and exchanges communication data with the communication control unit and the communication encryption unit respectively according to the Link Protocol and Serial_Link transmission protocols.

15. The vehicle-to-ground communication system applied to a train control system according to claim 13, characterized in that: The ground equipment also includes a radio block center, which is connected to the communication network.

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