A highly reliable and secure access method and system for acquisition and control terminals

Abstract

The present invention relates to a highly reliable and secure access method for acquisition and control terminals. Based on a business main station connected to an acquisition and control terminal via a secure access system, a main secure access gateway is designed to initiate identity authentication to the acquisition and control terminal based on a communication link. In combination with the encryption and decryption design between the two parties, a strict security authentication mechanism is established to effectively prevent network attacks and data leakage, thereby improving the security of the terminal and the business system. A secure access system is designed with dual secure access gateways. Through a highly reliable dual-machine hot standby mechanism, when a single secure access system fails, it can be quickly switched to ensure the continuity and real-time nature of the terminal acquisition and control business, thereby enhancing the stability and robustness of the business system. The present invention also designs a corresponding system, and through the specific module design of the acquisition and control terminal and the secure access system, the method execution process is subdivided to improve the accuracy and work efficiency of practical applications.

Description

Technical Field

[0001] The present invention relates to a highly reliable and secure access method and system for a collection and control terminal, belonging to the technical field of secure access control. Background Art

[0002] In the fields of smart grid, smart gas, smart water, etc., there are a large number of data collection and control terminals such as fault indicators, power distribution FTU, power distribution DTU, power distribution TTU, gas pressure regulating skid, RTU, PLC, etc., which are linked with distribution network SCADA system, gas SCADA, water SCADA and other systems to realize data collection and equipment control. At present, field data collection and control terminals are mainly connected to the business main station through optical fiber and other communication methods, but with the development of business, a large number of terminals are connected by wireless communication.

[0003] The existing security access process involves three entities: acquisition and control terminals, security access gateways, and business master station systems. The terminal access and business access process is as follows: Figure 1 As shown in the figure, most terminals use VPN mechanism to achieve secure access to business systems. However, the biggest problem with this method is that the business system can only passively receive connections initiated by the terminal and cannot distinguish the real IP of the network connection. In addition, the VPN mechanism cannot enable the business system to actively connect to the terminal and send control instructions. Therefore, the secure access method achieved by the traditional VPN mechanism cannot be directly applied to collection and control services.

[0004] In addition, as a security device, the secure access gateway is connected in series in the network between the terminal and the business system. Its robustness plays an important role in the real-time and stability of the business. Therefore, the current secure access gateway generally adopts a dual-machine hot standby method to solve the problem of business termination caused by a single gateway downtime or program crash. However, this method has the problem of too long hot standby switching time, which greatly affects the continuity of the business and cannot be applied to control-type businesses.

[0005] Therefore, existing secure access technologies and methods have improved the security of terminals and the robustness of services to a certain extent, but they still have the following shortcomings: (1) Existing data collection and control terminals lack effective identity authentication mechanisms, communication data lacks security protection, and traditional VPN access mechanisms cannot meet the SCADA system's requirements for direct operation of data collection and control terminals; (2) The dual-machine hot standby redundant switching mechanism of the traditional secure access gateway cannot guarantee uninterrupted access to the business by the acquisition and control terminals. During the switching process, there is a security risk that the control instructions cannot be issued, which has a great security impact on the stable operation of the business. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a highly reliable and secure access method and system for acquisition and control terminals, which not only ensures the legitimacy of the terminals, but also improves the security of the business and enhances the stability and robustness of the business system.

[0007] In order to solve the above technical problems, the present invention adopts the following technical solutions: the present invention designs a highly reliable and secure access method for acquisition and control terminals, based on that a business main station is connected to at least one acquisition control terminal via a secure access system, and the secure access system includes two secure access gateways that communicate with each other, and one of the two secure access gateways selectively accesses the communication link between the acquisition control terminal and the business main station; for each acquisition control terminal, the following steps A to B are performed to realize the control of the acquisition control terminal by the business main station; Step A. The secure access gateway connected to the communication link between the acquisition control terminal and the business master station constitutes the main secure access gateway, and the other secure access gateway constitutes the backup secure access gateway. The business master station establishes a target communication protocol connection with the acquisition control terminal via the main secure access gateway, and then proceeds to step B; Step B. The main security access gateway initiates identity authentication to the acquisition control terminal based on the target communication protocol connection information, and based on the successful identity authentication of the acquisition control terminal, the business main station initiates a control instruction to the acquisition control terminal via the main security access gateway based on the target communication protocol connection, and receives the response of the acquisition control terminal via the main security access gateway, thereby realizing the control of the acquisition control terminal by the business main station; While step A to step B are being executed, the two security access gateways communicate with each other according to a preset period, and according to the preset master-slave switching strategy, the master-slave status of the two security access gateways is switched. The master security access gateway accesses the communication link between the collection control terminal and the business main station, and the standby security access gateway disconnects from the communication link between the collection control terminal and the business main station, thereby realizing the switching of the master and standby access gateways.

[0008] As a preferred technical solution of the present invention: in the step A, the main security access gateway first forwards the ARP request initiated by the service master station to the acquisition control terminal, and the main security access gateway forwards the ARP response fed back by the acquisition control terminal to the service master station to confirm the IP communication between the service master station and the acquisition control terminal; The main security access gateway then forwards the target communication protocol connection initiated by the business master station to the acquisition control terminal, and the main security access gateway records the status of the target communication protocol connection process. After the target communication protocol connection is completed, the main security access gateway records the target communication protocol connection information.

[0009] As a preferred technical solution of the present invention: in the step B, identity authentication is completed according to the following steps B1 to B4; Step B1. The primary secure access gateway generates a random number , and combined with the preset public key corresponding to the control terminal IP in the target communication protocol connection information , encryption function using SM2 algorithm ,according to Encrypt and get ; And for SM3 hash result , combined with the preset private key corresponding to the main security access gateway in the target communication protocol connection information , the signature function of the SM2 algorithm is applied ,according to Sign and get ; Then the main security access gateway builds An identity authentication message corresponding to the target communication protocol is initiated and sent to the acquisition control terminal, and then the process goes to step B2; Step B2. The acquisition control terminal first connects the target communication protocol to the corresponding preset private key. , for the received identity authentication initiation message , decryption function using SM2 algorithm ,according to Decrypt it and get ; then for SM3 hash result , combined with the public key corresponding to the main secure access gateway , the signature verification function using the SM2 algorithm ,according to Perform signature verification. If the signature verification is successful, proceed to step B3; if the signature verification is unsuccessful, the identity authentication of the collection control terminal fails; Step B3. The acquisition control terminal generates a random number , and combined with the preset public key corresponding to the main security access gateway in the target communication protocol connection information , encryption function using SM2 algorithm ,according to Encrypt and get ; And for SM3 hash result , combined with the preset private key corresponding to the acquisition control terminal in the target communication protocol connection information , the signature function of the SM2 algorithm is applied ,according to Sign and get ; Then collect the control terminal connection information according to the target communication protocol, and build The identity authentication response message corresponding to the target communication protocol is returned to the main security access gateway, and then the process proceeds to step B4; Step B4. The main secure access gateway connects to the target communication protocol according to its corresponding preset private key , for the received authentication response message , decryption function using SM2 algorithm ,according to Decrypt it and get ; then for SM3 hash result , combined with the preset public key corresponding to the acquisition control terminal IP in the target communication protocol connection information , the signature verification function using the SM2 algorithm ,according to Perform signature verification. If the signature verification is successful, the identity authentication of the collection control terminal is successful; if the signature verification is unsuccessful, the identity authentication of the collection control terminal fails.

[0010] As a preferred technical solution of the present invention: the step B3 also includes: SM3 hash result Create a session key corresponding to the acquisition control terminal ; In step B4, based on the successful authentication of the acquisition control terminal, it also includes SM3 hash result Create a session key corresponding to the primary secure access gateway ; In the step B, based on the successful identity authentication of the acquisition control terminal, the business host station controls the acquisition control terminal according to the following steps B5 to B7; Step B5. The primary secure access gateway applies its corresponding session key , symmetrically encrypt the control instructions initiated by the business master station to the acquisition control terminal, and generate a control instruction encrypted message corresponding to the target communication protocol, send it to the acquisition control terminal, and enter step B6; Step B6. The acquisition control terminal encrypts the received control command message and applies the corresponding session key Decrypt, obtain the control instruction and execute it. If the control instruction requires a reply, the acquisition control terminal obtains the response result based on its response to the control instruction and applies its corresponding session key Encryption is performed, and then the ciphertext is generated to correspond to the instruction response encrypted message of the target communication protocol, which is returned to the main security access gateway and enters step B7; if the control instruction does not require a reply, the acquisition control terminal does not perform further processing; Step B7. The main secure access gateway responds to the received instruction encrypted message and applies its corresponding session key Decrypt it, obtain the response result, generate the command response message corresponding to the target communication protocol, and return it to the business main station.

[0011] As a preferred technical solution of the present invention: while the steps A to B are being executed, the following steps C to F are executed according to a preset period to implement the switching of the primary and standby secure access gateways; Step C. The main security access gateway shares the identity authentication status of the acquisition control terminal determined by it, and the data transmission status controlled by the acquisition control terminal, with the backup security access gateway, and proceeds to step D; Step D. The standby security access gateway initiates a status query to the main security access gateway; the main security access gateway receives the status query and feeds back to the standby security access gateway its own operating status, the status of the network port communicating with the standby security access gateway, and the communication status with the acquisition control terminal and the business terminal, and proceeds to step E; Step E. The standby security access gateway analyzes the received feedback according to the preset master-slave switching strategy, controls the master security access gateway and the standby security access gateway to remain unchanged, or controls the master security access gateway and the standby security access gateway to switch the master status, the new master security access gateway accesses the communication link between the collection control terminal and the service master station, the new standby security access gateway is disconnected from the communication link between the collection control terminal and the service master station, and then enters step F; Step F. The main security access gateway continues to implement the control of the acquisition control terminal by the service master station based on the identity authentication status of the acquisition control terminal and the data transmission status of the acquisition control terminal.

[0012] As a preferred technical solution of the present invention: in the step E, the standby secure access gateway analyzes the received feedback according to the preset active-standby switching strategy as follows to implement the active-standby access gateway switching; If the main security access gateway is operating normally and the communication status between the main security access gateway and the acquisition control terminal and the business terminal is normal, the control of the main security access gateway and the backup security access gateway remains unchanged; If the operation status of the main security access gateway is abnormal and the communication status between the main security access gateway and the collection control terminal and the business terminal is normal, the control of the main security access gateway and the backup security access gateway remains unchanged; If the main security access gateway is in normal operation, the communication status between the main security access gateway and the acquisition control terminal is abnormal, and the communication status between the main security access gateway and the business terminal is normal, the main security access gateway and the backup security access gateway are controlled to switch between the main and backup states; If the main security access gateway is in normal operation, the communication status between the main security access gateway and the acquisition control terminal is normal, and the communication status between the main security access gateway and the business terminal is abnormal, the main security access gateway and the backup security access gateway are controlled to switch between the main and backup states; If the operation status of the main security access gateway is abnormal, the communication status between the main security access gateway and the acquisition control terminal is normal, and the communication status between the main security access gateway and the business terminal is abnormal, the main security access gateway and the backup security access gateway are controlled to switch between the main and backup states; If the operating status of the main security access gateway is abnormal, and the communication status between the main security access gateway and the collection control terminal and the business terminal are abnormal, the main security access gateway and the backup security access gateway are controlled to switch between the main and backup states.

[0013] As a preferred technical solution of the present invention: the operation of controlling the main security access gateway and the backup security access gateway to switch between the main and backup states is analyzed. If the communication state between the main security access gateway and the acquisition control terminal is abnormal, or the communication state between the main security access gateway and the service terminal is abnormal, the original main security access gateway is first controlled to switch to the new backup security access gateway, and then the original backup security access gateway is controlled to switch to the new main security access gateway; If the operating status of the main security access gateway is abnormal and the communication status between the main security access gateway and the collection control terminal and the business terminal are abnormal, the original backup security access gateway is directly controlled to switch to the new main security access gateway.

[0014] Corresponding to the above, the technical problem that the present invention also needs to solve is to provide a highly reliable and secure access method and system for collection and control terminals, which not only ensures the legitimacy of the terminals, but also improves the security of the business and enhances the stability and robustness of the business system.

[0015] In order to solve the above technical problems, the present invention adopts the following technical solutions: The present invention designs a system of highly reliable and secure access method for acquisition and control terminals, which is easy to modularize and realizes the security and efficiency of terminal access system.

[0016] In order to solve the above technical problems, the present invention adopts the following technical solutions: the present invention designs a system of a highly reliable and secure access method for acquisition and control terminals, wherein the structures of the acquisition and control terminals are the same, and each acquisition and control terminal includes a business module, an identity authentication module, a data encryption and decryption module, and a communication module. In the structure of the acquisition and control terminal, the business module is respectively connected to the identity authentication module and the data encryption and decryption module, the identity authentication module is connected to the data encryption and decryption module, and the identity authentication module and the data encryption and decryption module are respectively connected to the communication module; The structures of the two security access gateways in the security access system are identical to each other. Each security access gateway includes an external network communication module, an internal network communication module, an identity authentication module, and a data encryption and decryption module. In the structure of the security access gateway, the data encryption and decryption module is respectively connected to the external network communication module and the internal network communication module, and the identity authentication module is respectively connected to the external network communication module and the data encryption and decryption module; The communication module in the acquisition control terminal is connected to the external network communication module in the security access gateway, and the internal network communication module in the security access gateway is connected to the business main station; The business main station sequentially passes through the intranet communication module, data encryption and decryption module, and extranet communication module in the main security access gateway to the communication module in the acquisition control terminal, forming a communication link between the business main station and the acquisition control terminal. The intranet communication module in the main security access gateway and the communication module in the acquisition control terminal establish a target communication protocol connection based on the communication link; the identity authentication module in the main security access gateway and the identity authentication module in the acquisition control terminal are used to perform steps B1 to B4 based on the communication link to complete the identity authentication, and the data encryption and decryption module in the main security access gateway is used for the encryption and decryption operations of the data in the identity authentication process corresponding to the identity authentication module in the main security access gateway, as well as the signature and signature verification operations, and the data encryption and decryption module in the acquisition control terminal is used for the encryption and decryption operations of the data in the identity authentication process corresponding to the identity authentication module in the acquisition control terminal, as well as the signature and signature verification operations; The business main station executes steps B5 to B7 based on the communication link, sends control instructions to the acquisition control terminal, and transmits the control instructions to the business module through the data encryption and decryption module in the acquisition control terminal. The business module receives the control instructions and responds, wherein the data encryption and decryption module in the main security access gateway and the data encryption and decryption module in the acquisition control terminal are used for data encryption and decryption operations.

[0017] As a preferred technical solution of the present invention: each secure access gateway further comprises a state synchronization module, a master-slave control module, an external network heartbeat module, a master-slave heartbeat module, an internal network heartbeat module, and a heartbeat communication module; in the secure access gateway structure, the state synchronization module is respectively connected to the identity authentication module, the data encryption and decryption module, and the heartbeat communication module; the master-slave control module is respectively connected to the external network heartbeat module, the master-slave heartbeat module, and the internal network heartbeat module; the external network heartbeat module is connected to the external network communication module; the internal network heartbeat module is connected to the internal network communication module; and the master-slave heartbeat module is connected to the heartbeat communication module at the same time; The heartbeat communication modules in the two secure access gateways are connected to each other for communication. Based on the virtual network cards preset on the external network communication module and the internal network communication module in each secure access gateway, the external network heartbeat modules in the two secure access gateways communicate with each other via the virtual network cards on the external network communication modules to which they are connected, and the internal network heartbeat modules in the two secure access gateways communicate with each other via the virtual network cards on the internal network communication modules to which they are connected; The state synchronization module in the main security access gateway executes step C via the heartbeat communication module to share the identity authentication state of the acquisition control terminal and the data transmission state to the standby security access gateway; During the execution of step D, the active-standby heartbeat module in the standby security access gateway initiates a status inquiry to the heartbeat communication module and the active-standby heartbeat module in the primary security access gateway via the heartbeat communication module to which it is connected, and receives a status reply from the active-standby heartbeat module in the primary security access gateway; the external network heartbeat module in the standby security access gateway is used to initiate a status inquiry to the external network heartbeat module in the primary security access gateway, and receives a status reply from the external network heartbeat module in the primary security access gateway; the intranet heartbeat module in the standby security access gateway is used to initiate a status inquiry to the intranet heartbeat module in the primary security access gateway, and receives a status reply from the intranet heartbeat module in the primary security access gateway; The active-standby control module in the standby security access gateway receives the status of the active security access gateway uploaded by the external network heartbeat module, the active-standby heartbeat module, and the intranet heartbeat module to which it is connected, executes step E, contacts the active-standby control module in the active security access gateway, and implements active-standby access gateway switching for the active security access gateway and the standby security access gateway.

[0018] The highly reliable and secure access method and system for acquisition and control terminals described in the present invention adopt the above technical solution and have the following technical effects compared with the prior art: The present invention designs a highly reliable and secure access method for acquisition and control terminals. The method is based on connecting the acquisition and control terminals to the business main station via a secure access system. The method is designed such that the main secure access gateway initiates identity authentication to the acquisition and control terminals based on a communication link. The method combines the encryption and decryption design between the two parties to establish a strict security authentication mechanism, effectively preventing network attacks and data leakage, and improving the security of the terminals and business systems. The secure access system is designed with dual secure access gateways. Through a highly reliable dual-machine hot standby mechanism, when a single secure access system fails, it can quickly switch to ensure the continuity and real-time nature of the terminal acquisition and control services, and enhance the stability and robustness of the business system. The present invention also designs a corresponding system, which subdivides the method execution process through the specific module design of the acquisition and control terminals and the secure access system, and improves the accuracy and work efficiency of practical applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the existing terminal access and service access process; Figure 2 It is a schematic diagram of the system architecture of the highly reliable and secure access method for acquisition and control terminals designed by the present invention; Figure 3 It is a schematic diagram of the architecture of the acquisition control terminal in the design of the present invention; Figure 4 It is a schematic diagram of the architecture of the secure access gateway in the design of the present invention; Figure 5 It is a schematic diagram of the process of identity authentication in the design of the present invention; Figure 6 It is a schematic diagram of the architecture of the switching of the primary and standby access gateways in the design of the present invention. DETAILED DESCRIPTION

[0020] The specific implementation modes of the present invention will be further described in detail below in conjunction with the accompanying drawings.

[0021] In view of the shortcomings of the prior art, the present invention proposes the following specific design ideas: Design a secure access method for acquisition control terminals, implement the terminal identity authentication and key negotiation mechanism without changing the original business communication mode, which not only ensures the legitimacy of the terminal, but also improves the security of the business; Design a highly reliable dual-machine hot standby mechanism for secure access gateways suitable for control services. When a single secure access gateway fails, it can quickly switch to ensure the continuity and real-time performance of acquisition and control services, and enhance the stability and robustness of the business system. A highly reliable and secure access system for acquisition and control terminals is provided, including an acquisition and control terminal, a secure access gateway and a business master station SCADA system; the secure access gateway is deployed in series between the acquisition and control terminal and the business master station SCADA system in a hot standby manner, which realizes identity authentication of the acquisition and control terminal without changing the original business communication mode.

[0022] According to the above design ideas, the present invention specifically designs a highly reliable and secure access method and system for acquisition and control terminals, such as Figure 2 As shown, the design system includes a business master station SCADA system, a security access system, and at least one acquisition control terminal. The business master station SCADA system is connected to at least one acquisition control terminal via the security access system. The security access system includes two security access gateways that communicate with each other, and one of the two security access gateways selectively accesses the communication link between the acquisition control terminal and the business master station SCADA system.

[0023] In actual applications, the structures of the acquisition and control terminals are designed to be the same as each other, such as Figure 3 As shown, each acquisition and control terminal includes a business module, an identity authentication module, a data encryption and decryption module, and a communication module. In the acquisition and control terminal structure, the business module is communicated with the identity authentication module and the data encryption and decryption module respectively, the identity authentication module is communicated with the data encryption and decryption module, and the identity authentication module and the data encryption and decryption module are communicated with the communication module respectively.

[0024] like Figure 4 As shown, each security access gateway includes an external network communication module, an internal network communication module, an identity authentication module, a data encryption and decryption module, a status synchronization module, an active-standby control module, an external network heartbeat module, an active-standby heartbeat module, an internal network heartbeat module, and a heartbeat communication module. In the structure of the security access gateway, the data encryption and decryption module is respectively communicated with the external network communication module and the internal network communication module, the identity authentication module is respectively communicated with the external network communication module and the data encryption and decryption module, the status synchronization module is respectively communicated with the identity authentication module, the data encryption and decryption module, and the heartbeat communication module, the active-standby control module is respectively communicated with the external network heartbeat module, the active-standby heartbeat module, and the internal network heartbeat module, the external network heartbeat module is communicated with the external network communication module, the internal network heartbeat module is communicated with the internal network communication module, and the active-standby heartbeat modules are simultaneously communicated with the heartbeat communication module.

[0025] In the secure access system structure, the heartbeat communication modules in the two secure access gateways communicate with each other, based on the virtual network cards preset and configured on the external network communication modules and the internal network communication modules in each secure access gateway. , , and the corresponding assigned IP address, the external network heartbeat modules in the two secure access gateways are respectively connected through the virtual network cards on the external network communication modules to which they are connected To achieve mutual communication, the intranet heartbeat modules in the two secure access gateways communicate with each other through the virtual network cards on the intranet communication modules to which they are connected. Realize mutual communication and adopt dual-machine deployment to achieve high reliability and high stability of terminal access.

[0026] The communication module in the acquisition control terminal is connected to the external network communication module in the security access gateway, and the internal network communication module in the security access gateway is connected to the business master station SCADA system; the business master station SCADA system passes through the internal network communication module, data encryption and decryption module, and external network communication module in the main security access gateway to the communication module in the acquisition control terminal, forming a communication link between the business master station SCADA system and the acquisition control terminal.

[0027] Based on the above system design, the present invention specifically designs a highly reliable and secure access method for acquisition and control terminals. In actual application, for each acquisition and control terminal, the following steps A to B are executed to realize the control of the acquisition and control terminals by the business master station SCADA system.

[0028] Step A. The security access gateway connected to the communication link between the acquisition control terminal and the business master station SCADA system constitutes the main security access gateway, and the other security access gateway constitutes the backup security access gateway. First, the main security access gateway forwards the ARP request initiated by the business master station SCADA system to the acquisition control terminal, and the main security access gateway forwards the ARP response fed back by the acquisition control terminal to the business master station SCADA system to confirm the IP communication between the business master station SCADA system and the acquisition control terminal.

[0029] The main security access gateway then forwards the target communication protocol connection, such as a TCP connection, initiated by the business master station SCADA system to the acquisition control terminal, and the main security access gateway records the status of the TCP connection three-step handshake. After the target communication protocol connection is completed, the main security access gateway records the TCP connection information and then enters step B.

[0030] Step B. The main security access gateway initiates identity authentication to the collection control terminal based on the TCP connection information, and based on the successful identity authentication of the collection control terminal, the business master station SCADA system initiates control instructions to the collection control terminal through the main security access gateway based on the target communication protocol connection, and receives the response of the collection control terminal through the main security access gateway, thereby realizing the control of the collection control terminal by the business master station SCADA system.

[0031] In practical applications, in the above step B, if Figure 5 As shown, the specific design executes the following steps B1 to B4 to complete identity authentication.

[0032] Step B1. The identity authentication module in the main secure access gateway generates a random number , and combined with the preset public key corresponding to the control terminal IP in the TCP connection information , the encryption function of the SM2 algorithm is applied by the data encryption and decryption module ,according to Encrypt and get .

[0033] And for SM3 hash result , combined with the preset private key corresponding to the main security access gateway in the target communication protocol connection information , the signature function of the SM2 algorithm is applied by the data encryption module ,according to Sign and get .

[0034] Then the identity authentication module in the main security access gateway builds a The identity authentication initiation message corresponding to the TCP connection is sent to the collection control terminal through the external network communication module, and then enters step B2.

[0035] Step B2. The identity authentication module in the acquisition control terminal receives the identity authentication initiation message through the communication module to which it is connected. First, according to the preset private key corresponding to the TCP connection information , for the identity authentication initiation message , the decryption function of the SM2 algorithm is applied by the data encryption and decryption module ,according to Decrypt it and get ; then for SM3 hash result , combined with the public key corresponding to the main secure access gateway , the data encryption and decryption module applies the SM2 algorithm to verify the signature function ,according to Perform signature verification. If the signature verification is successful, feedback is sent to the identity authentication module and the process goes to step B3. If the signature verification is unsuccessful, feedback is sent to the identity authentication module that the identity authentication of the collection control terminal has failed.

[0036] Step B3. The identity authentication module in the acquisition control terminal generates a random number , combined with the preset public key corresponding to the primary secure access gateway in the TCP connection information , the encryption function of the SM2 algorithm is applied by the data encryption and decryption module ,according to Encrypt and get .

[0037] And for SM3 hash result , combined with the preset private key corresponding to the acquisition control terminal in the target communication protocol connection information , the signature function of the SM2 algorithm is applied by the data encryption and decryption module ,according to Sign and get .

[0038] Then the identity authentication module in the acquisition control terminal builds a The corresponding TCP connection authentication response message is returned to the main security access gateway through the communication module, and the data encryption and decryption module is used to SM3 hash result Create a session key corresponding to the acquisition control terminal , then go to step B4.

[0039] Step B4. The authentication module in the main secure access gateway receives the authentication response message via its connected external network communication module, according to the TCP connection information corresponding to the preset private key of the main secure access gateway. , for the authentication response message , the decryption function of the SM2 algorithm is applied by the data encryption and decryption module ,according to Decrypt it and get ; then for SM3 hash result , combined with the preset public key corresponding to the control terminal IP in the TCP connection information , the data encryption and decryption module applies the SM2 algorithm to verify the signature function ,according to If the signature verification is successful, the identity authentication module will be informed that the identity authentication of the acquisition control terminal is successful. SM3 hash result Create a session key corresponding to the primary secure access gateway , then proceed to step B5; if the signature verification fails, the identity authentication failure of the collection control terminal is fed back to the identity authentication module.

[0040] Step B5. The intranet communication module in the main security access gateway receives the control command initiated by the business master SCADA system to the acquisition control terminal and sends it to the data encryption and decryption module, which applies the session key corresponding to the main security access gateway. , perform symmetrical encryption on the control instruction, and generate a control instruction encrypted message corresponding to the ciphertext TCP connection, which is sent to the collection control terminal via the external network communication module, and enter step B6.

[0041] Step B6. The communication module in the acquisition control terminal receives the encrypted control command message and sends it to the data encryption and decryption module, which applies the session key corresponding to the acquisition control terminal. Decrypt the data, obtain the control instruction, and send it to the business module for execution. If the control instruction requires a reply, the response result is returned to the data encryption and decryption module based on the business module's response to the control instruction. The data encryption and decryption module collects the session key corresponding to the control terminal. Encryption is performed, and then the ciphertext corresponding to the TCP connection command response encrypted message is generated, which is returned to the main security access gateway through the communication module and enters step B7; if the control instruction does not require a reply, the business module in the acquisition control terminal does not perform further processing.

[0042] Step B7. The external network communication module in the main secure access gateway receives the command response encrypted message and forwards it to the data encryption and decryption module, which applies the session key corresponding to the main secure access gateway. Decryption is performed to obtain the response result, and a command response message corresponding to the TCP connection is generated and returned to the business master station SCADA system through the intranet communication module.

[0043] The design and execution of step B above does not modify the original communication logic of the service, which solves the problem of service interruption caused by network address translation under the traditional VPN mechanism, and at the same time enhances the credibility of the terminal identity during the service communication process and the non-repudiation of communication.

[0044] In order to ensure the stable and highly reliable operation of the secure access gateway and to ensure that the service is not interrupted due to abnormal reasons such as the crash or downtime of a single secure access gateway, a highly reliable network dual-machine hot standby and switching mechanism is designed. By adding multiple heartbeat line mechanisms, the high availability of the secure access service is achieved, that is, a highly reliable gateway dual-machine hot standby and switching mechanism is designed.

[0045] Therefore, while step A to step B are being executed, the two security access gateways communicate with each other according to a preset period, and according to the preset master-slave switching strategy, the master-slave status of the two security access gateways is switched. The master security access gateway accesses the communication link between the collection control terminal and the business master station SCADA system, and the standby security access gateway disconnects from the communication link between the collection control terminal and the business master station SCADA system, thereby realizing the switching of the master-slave access gateway.

[0046] In practical applications, such as Figure 6As shown, the following steps C to F are performed according to a preset period to implement the switching of the primary and standby secure access gateways.

[0047] Step C. Based on the communication between the heartbeat communication module in the primary security access gateway and the heartbeat communication module in the standby security access gateway, the status synchronization module in the primary security access gateway shares the identity authentication status of the acquisition control terminal determined by the identity authentication module and the data transmission status of the acquisition control terminal controlled by its data encryption and decryption module with the status synchronization module in the standby security access gateway, and sends them to the identity authentication module and the data encryption and decryption module in the standby security access gateway, and then enters step D.

[0048] Step D. Based on the communication between the heartbeat communication module in the primary security access gateway and the heartbeat communication module in the standby security access gateway, the active-standby heartbeat module in the standby security access gateway initiates a status inquiry to the heartbeat communication module and the active-standby heartbeat module in the primary security access gateway via the heartbeat communication module to which it is connected, and receives a status reply from the active-standby heartbeat module in the primary security access gateway; the external network heartbeat module in the standby security access gateway initiates a status inquiry to the external network heartbeat module in the primary security access gateway via the external network communication module, and receives a status reply from the external network heartbeat module in the primary security access gateway; the intranet heartbeat module in the standby security access gateway initiates a status inquiry to the intranet heartbeat module in the primary security access gateway via the intranet communication module, and receives a status reply from the intranet heartbeat module in the primary security access gateway, and then proceeds to step E.

[0049] Step E. The active-standby control module in the standby security access gateway receives the status of the active security access gateway uploaded by the external network heartbeat module, the active-standby heartbeat module, and the internal network heartbeat module to which it is connected, analyzes the received feedback according to the preset active-standby switching strategy, contacts the active-standby control module in the active security access gateway, controls the active security access gateway and the standby security access gateway to remain unchanged, or controls the active-standby status of the active-standby access gateway and the standby security access gateway to switch, the new active security access gateway accesses the communication link between the acquisition control terminal and the business master station SCADA system, the new standby security access gateway disconnects from the communication link between the acquisition control terminal and the business master station SCADA system, and then enters step F.

[0050] In actual applications, the specific design of the preset active / standby switching strategy is as follows: If the main security access gateway is operating normally and the communication status between the main security access gateway and the acquisition control terminal and the business terminal is normal, the control of the main security access gateway and the backup security access gateway remains unchanged; If the operation status of the main security access gateway is abnormal and the communication status between the main security access gateway and the collection control terminal and the business terminal is normal, the control of the main security access gateway and the backup security access gateway remains unchanged; If the main security access gateway is in normal operation, the communication status between the main security access gateway and the acquisition control terminal is abnormal, and the communication status between the main security access gateway and the business terminal is normal, the main security access gateway and the backup security access gateway are controlled to switch between the main and backup states; If the main security access gateway is in normal operation, the communication status between the main security access gateway and the acquisition control terminal is normal, and the communication status between the main security access gateway and the business terminal is abnormal, the main security access gateway and the backup security access gateway are controlled to switch between the main and backup states; If the operation status of the main security access gateway is abnormal, the communication status between the main security access gateway and the acquisition control terminal is normal, and the communication status between the main security access gateway and the business terminal is abnormal, the main security access gateway and the backup security access gateway are controlled to switch between the main and backup states; If the operating status of the main security access gateway is abnormal, and the communication status between the main security access gateway and the collection control terminal and the business terminal are abnormal, the main security access gateway and the backup security access gateway are controlled to switch between the main and backup states.

[0051] Regarding the further design of the preset active-standby switching strategy in practice, the operation of controlling the active-standby state switching of the active and standby security access gateways is analyzed.

[0052] If the communication status between the main security access gateway and the collection control terminal is abnormal, or the communication status between the main security access gateway and the business terminal is abnormal, first control the original main security access gateway to switch to the new backup security access gateway, and then control the original backup security access gateway to switch to the new main security access gateway.

[0053] If the operating status of the main security access gateway is abnormal and the communication status between the main security access gateway and the collection control terminal and the business terminal are abnormal, the original backup security access gateway is directly controlled to switch to the new main security access gateway.

[0054] After executing step E as described above, further execute the following step F.

[0055] Step F. The main security access gateway continues to implement the control of the acquisition control terminal by the business master station SCADA system based on the identity authentication status of the acquisition control terminal and the data transmission status of the acquisition control terminal control.

[0056] The highly reliable and secure access method for acquisition and control terminals designed in the above technical scheme is based on the business main station connecting to the acquisition and control terminals via the security access system, and is designed to initiate identity authentication to the acquisition and control terminals based on the communication link by the main security access gateway. Combined with the encryption and decryption design between the two parties, a strict security authentication mechanism is established to effectively prevent network attacks and data leakage, and improve the security of terminals and business systems; a security access system is designed with dual security access gateways, and through a highly reliable dual-machine hot standby mechanism, when a single security access system fails, it can be quickly switched to ensure the continuity and real-time nature of the terminal acquisition and control business, and enhance the stability and robustness of the business system; the present invention also designs a corresponding system, through the specific module design of the acquisition and control terminals and the security access system, the method execution process is subdivided to improve the accuracy and work efficiency of practical applications.

[0057] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge scope of ordinary technicians in this field without departing from the purpose of the present invention.

Claims

1. A highly reliable and secure access method for acquisition and control terminals, characterized by: Based on the business main station being connected to at least one acquisition control terminal via a security access system, and the security access system comprising two security access gateways communicating with each other, and one of the two security access gateways selectively accessing the communication link between the acquisition control terminal and the business main station; for each acquisition control terminal, executing the following steps A to B respectively, to realize the control of the acquisition control terminal by the business main station; Step A. The secure access gateway connected to the communication link between the acquisition control terminal and the business master station constitutes the main secure access gateway, and the other secure access gateway constitutes the backup secure access gateway. The business master station establishes a target communication protocol connection with the acquisition control terminal via the main secure access gateway, and then proceeds to step B; Step B. The main security access gateway initiates identity authentication to the acquisition control terminal based on the target communication protocol connection information, and based on the successful identity authentication of the acquisition control terminal, the business main station initiates a control instruction to the acquisition control terminal via the main security access gateway based on the target communication protocol connection, and receives the response of the acquisition control terminal via the main security access gateway, thereby realizing the control of the acquisition control terminal by the business main station; While step A to step B are being executed, the two security access gateways communicate with each other according to a preset period, and according to the preset master-slave switching strategy, the master-slave status of the two security access gateways is switched. The master security access gateway accesses the communication link between the collection control terminal and the business main station, and the standby security access gateway disconnects from the communication link between the collection control terminal and the business main station, thereby realizing the switching of the master and standby access gateways.

2. According to claim 1, a highly reliable and secure access method for acquisition and control terminals is characterized by: In step A, the main security access gateway first forwards the ARP request initiated by the service master station to the acquisition control terminal, and the main security access gateway forwards the ARP response fed back by the acquisition control terminal to the service master station to confirm the IP communication between the service master station and the acquisition control terminal; The main security access gateway then forwards the target communication protocol connection initiated by the business master station to the acquisition control terminal, and the main security access gateway records the status of the target communication protocol connection process. After the target communication protocol connection is completed, the main security access gateway records the target communication protocol connection information.

3. A highly reliable and secure access method for acquisition and control terminals according to claim 1 or 2, characterized in that: In step B, identity authentication is completed according to steps B1 to B4 as follows; Step B1. The primary secure access gateway generates a random number , and combined with the preset public key corresponding to the control terminal IP in the target communication protocol connection information , encryption function using SM2 algorithm ,according to Encrypt and get ; And for SM3 hash result , combined with the preset private key corresponding to the main security access gateway in the target communication protocol connection information , the signature function of the SM2 algorithm is applied ,according to Sign and get ; Then the main security access gateway builds An identity authentication message corresponding to the target communication protocol is initiated and sent to the acquisition control terminal, and then step B2 is entered; Step B2. The acquisition control terminal first connects the target communication protocol to the corresponding preset private key. , for the received identity authentication initiation message , decryption function using SM2 algorithm ,according to Decrypt it and get ; then for SM3 hash result , combined with the public key corresponding to the main secure access gateway , the signature verification function using the SM2 algorithm ,according to Perform signature verification. If the signature verification is successful, proceed to step B3; if the signature verification is unsuccessful, the identity authentication of the collection control terminal fails; Step B3. The acquisition control terminal generates a random number , and combined with the preset public key corresponding to the main security access gateway in the target communication protocol connection information , encryption function using SM2 algorithm ,according to Encrypt and get ; And for SM3 hash result , combined with the preset private key corresponding to the acquisition control terminal in the target communication protocol connection information , the signature function of the SM2 algorithm is applied ,according to Sign and get ; Then collect the control terminal connection information according to the target communication protocol, and build The identity authentication response message corresponding to the target communication protocol is returned to the main security access gateway, and then the process proceeds to step B4; Step B4. The main secure access gateway connects to the target communication protocol according to its corresponding preset private key , for the received authentication response message , decryption function using SM2 algorithm ,according to Decrypt it and get ; then for SM3 hash result , combined with the preset public key corresponding to the acquisition control terminal IP in the target communication protocol connection information , the signature verification function using the SM2 algorithm ,according to Perform signature verification. If the signature verification is successful, the identity authentication of the collection control terminal is successful; if the signature verification is unsuccessful, the identity authentication of the collection control terminal fails.

4. According to claim 3, a highly reliable and secure access method for acquisition and control terminals is characterized by: The step B3 also includes: SM3 hash result Create a session key corresponding to the acquisition control terminal ; In step B4, based on the successful authentication of the acquisition control terminal, it also includes SM3 hash result Create a session key corresponding to the primary secure access gateway ; In the step B, based on the successful identity authentication of the acquisition control terminal, the business host station controls the acquisition control terminal according to the following steps B5 to B7; Step B5. The primary secure access gateway applies its corresponding session key , symmetrically encrypt the control instructions initiated by the business master station to the acquisition control terminal, and generate a control instruction encrypted message corresponding to the target communication protocol, send it to the acquisition control terminal, and enter step B6; Step B6. The acquisition control terminal encrypts the received control command message and applies the corresponding session key Decrypt, obtain the control instruction and execute it. If the control instruction requires a reply, the acquisition control terminal obtains the response result based on its response to the control instruction and applies its corresponding session key Encryption is performed, and then the ciphertext is generated to correspond to the instruction response encrypted message of the target communication protocol, which is returned to the main security access gateway and enters step B7; if the control instruction does not require a reply, the acquisition control terminal does not perform further processing; Step B7. The main secure access gateway responds to the received instruction encrypted message and applies its corresponding session key Decrypt it, obtain the response result, generate the command response message corresponding to the target communication protocol, and return it to the business main station.

5. According to claim 4, a highly reliable and secure access method for acquisition and control terminals is characterized in that: While the steps A to B are being executed, the following steps C to F are executed according to a preset period to implement the switching of the primary and standby secure access gateways; Step C. The main security access gateway shares the identity authentication status of the acquisition control terminal determined by it, and the data transmission status controlled by the acquisition control terminal, with the backup security access gateway, and proceeds to step D; Step D. The standby security access gateway initiates a status query to the main security access gateway; the main security access gateway receives the status query and feeds back to the standby security access gateway its own operating status, the status of the network port communicating with the standby security access gateway, and the communication status with the acquisition control terminal and the business terminal, and proceeds to step E; Step E. The standby security access gateway analyzes the received feedback according to the preset master-slave switching strategy, controls the master security access gateway and the standby security access gateway to remain unchanged, or controls the master security access gateway and the standby security access gateway to switch the master status, the new master security access gateway accesses the communication link between the collection control terminal and the service master station, the new standby security access gateway is disconnected from the communication link between the collection control terminal and the service master station, and then enters step F; Step F. The main security access gateway continues to implement the control of the acquisition control terminal by the service master station based on the identity authentication status of the acquisition control terminal and the data transmission status of the acquisition control terminal.

6. According to claim 5, a highly reliable and secure access method for acquisition and control terminals is characterized in that: In the step E, the standby secure access gateway analyzes the received feedback according to the preset active-standby switching strategy as follows to implement active-standby access gateway switching; If the main security access gateway is operating normally and the communication status between the main security access gateway and the acquisition control terminal and the business terminal is normal, the control of the main security access gateway and the backup security access gateway remains unchanged; If the operation status of the main security access gateway is abnormal and the communication status between the main security access gateway and the collection control terminal and the business terminal is normal, the control of the main security access gateway and the backup security access gateway remains unchanged; If the main security access gateway is in normal operation, the communication status between the main security access gateway and the acquisition control terminal is abnormal, and the communication status between the main security access gateway and the business terminal is normal, the main security access gateway and the backup security access gateway are controlled to switch between the main and backup states; If the main security access gateway is in normal operation, the communication status between the main security access gateway and the acquisition control terminal is normal, and the communication status between the main security access gateway and the business terminal is abnormal, the main security access gateway and the backup security access gateway are controlled to switch between the main and backup states; If the operation status of the main security access gateway is abnormal, the communication status between the main security access gateway and the acquisition control terminal is normal, and the communication status between the main security access gateway and the business terminal is abnormal, the main security access gateway and the backup security access gateway are controlled to switch between the main and backup states; If the operating status of the main security access gateway is abnormal, and the communication status between the main security access gateway and the collection control terminal and the business terminal are abnormal, the main security access gateway and the backup security access gateway are controlled to switch between the main and backup states.

7. According to claim 6, a highly reliable and secure access method for acquisition and control terminals, characterized in that: Analyze the operation of controlling the main security access gateway and the backup security access gateway to switch between the main and backup states. If the communication state between the main security access gateway and the acquisition control terminal is abnormal, or the communication state between the main security access gateway and the service terminal is abnormal, first control the original main security access gateway to switch to the new backup security access gateway, and then control the original backup security access gateway to switch to the new main security access gateway; If the operating status of the main security access gateway is abnormal and the communication status between the main security access gateway and the collection control terminal and the business terminal are abnormal, the original backup security access gateway is directly controlled to switch to the new main security access gateway.

8. A system for implementing the highly reliable and secure access method for acquisition and control terminals as described in claim 7, characterized in that: The structures of the acquisition control terminals are the same as each other. Each acquisition control terminal includes a business module, an identity authentication module, a data encryption and decryption module, and a communication module. In the acquisition control terminal structure, the business module is connected to the identity authentication module and the data encryption and decryption module, the identity authentication module is connected to the data encryption and decryption module, and the identity authentication module and the data encryption and decryption module are connected to the communication module. The structures of the two security access gateways in the security access system are identical to each other. Each security access gateway includes an external network communication module, an internal network communication module, an identity authentication module, and a data encryption and decryption module. In the structure of the security access gateway, the data encryption and decryption module is respectively connected to the external network communication module and the internal network communication module, and the identity authentication module is respectively connected to the external network communication module and the data encryption and decryption module; The communication module in the acquisition control terminal is connected to the external network communication module in the security access gateway, and the internal network communication module in the security access gateway is connected to the business main station; The business main station sequentially passes through the intranet communication module, data encryption and decryption module, and extranet communication module in the main security access gateway to the communication module in the acquisition control terminal, forming a communication link between the business main station and the acquisition control terminal. The intranet communication module in the main security access gateway and the communication module in the acquisition control terminal establish a target communication protocol connection based on the communication link; the identity authentication module in the main security access gateway and the identity authentication module in the acquisition control terminal are used to perform steps B1 to B4 based on the communication link to complete the identity authentication, and the data encryption and decryption module in the main security access gateway is used for the encryption and decryption operations of the data in the identity authentication process corresponding to the identity authentication module in the main security access gateway, as well as the signature and signature verification operations, and the data encryption and decryption module in the acquisition control terminal is used for the encryption and decryption operations of the data in the identity authentication process corresponding to the identity authentication module in the acquisition control terminal, as well as the signature and signature verification operations; The business main station executes steps B5 to B7 based on the communication link, sends control instructions to the acquisition control terminal, and transmits the control instructions to the business module through the data encryption and decryption module in the acquisition control terminal. The business module receives the control instructions and responds, wherein the data encryption and decryption module in the main security access gateway and the data encryption and decryption module in the acquisition control terminal are used for data encryption and decryption operations.

9. The system according to claim 8, characterized in that: Each security access gateway also includes a state synchronization module, a master-slave control module, an external network heartbeat module, a master-slave heartbeat module, an internal network heartbeat module, and a heartbeat communication module; in the security access gateway structure, the state synchronization module is respectively connected to the identity authentication module, the data encryption and decryption module, and the heartbeat communication module; the master-slave control module is respectively connected to the external network heartbeat module, the master-slave heartbeat module, and the internal network heartbeat module; the external network heartbeat module is connected to the external network communication module; the internal network heartbeat module is connected to the internal network communication module; and the master-slave heartbeat module is connected to the heartbeat communication module at the same time; The heartbeat communication modules in the two secure access gateways are connected to each other for communication. Based on the virtual network cards preset on the external network communication module and the internal network communication module in each secure access gateway, the external network heartbeat modules in the two secure access gateways communicate with each other via the virtual network cards on the external network communication modules to which they are connected, and the internal network heartbeat modules in the two secure access gateways communicate with each other via the virtual network cards on the internal network communication modules to which they are connected; The state synchronization module in the main security access gateway executes step C via the heartbeat communication module to share the identity authentication state of the acquisition control terminal and the data transmission state to the standby security access gateway; During the execution of step D, the active-standby heartbeat module in the standby security access gateway initiates a status inquiry to the heartbeat communication module and the active-standby heartbeat module in the primary security access gateway via the heartbeat communication module to which it is connected, and receives a status reply from the active-standby heartbeat module in the primary security access gateway; the extranet heartbeat module in the standby security access gateway is used to initiate a status inquiry to the extranet heartbeat module in the primary security access gateway, and receive a status reply from the extranet heartbeat module in the primary security access gateway; The intranet heartbeat module in the standby security access gateway is used to initiate a status query to the intranet heartbeat module in the primary security access gateway, and receive a status reply from the intranet heartbeat module in the primary security access gateway; The active-standby control module in the standby security access gateway receives the status of the active security access gateway uploaded by the external network heartbeat module, the active-standby heartbeat module, and the intranet heartbeat module to which it is connected, executes step E, contacts the active-standby control module in the active security access gateway, and implements active-standby access gateway switching for the active security access gateway and the standby security access gateway.

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