Power system AMI information security transmission method based on improved endogenous security

Abstract

The invention discloses an improved endogenous security-based power system AMI information security transmission method. The method comprises the following steps of: randomly dividing a message into three sub-messages with different lengths by using a message segmentation algorithm; processing the three sub-messages by using a heterogeneous redundancy encryption executor to obtain three sub-ciphertexts and message authentication codes, synthesizing the three sub-ciphertexts and the message authentication codes into AEP, and sending the AEP to a data concentrator; the data concentrator decomposes the AEP to obtain three sub-ciphertexts and a message authentication code, and processes the three sub-ciphertexts by using a heterogeneous redundancy decryption executor to obtain three sub-messages; and the data concentrator synthesizes the sub-messages into an unauthenticated message, the message authentication function processes the unauthenticated message to obtain the MAC1, the MAC is compared with the MAC1, if the MAC is the same as the MAC1, the message is output, and if the MAC is different from the MAC1, the information is tampered and the information is sent again. According to the method, efficient and stable AMI information secure transmission can be realized, and the overall security of the system is effectively guaranteed.

Description

Technical Field

[0001] The present invention belongs to the field of power system information security, and relates to a power system advanced measurement architecture (AMI) information security transmission method, and specifically to a power system AMI information security transmission method based on improved intrinsic security. Background Art

[0002] In the context of global energy transformation and smart grid construction, AMI has become an important part of the new power system. Through smart meters, communication networks and data management platforms, AMI helps to achieve intelligent matching between user power demand and power grid power supply capacity, and supports real-time collection, remote control and two-way information interaction of power consumption data. This not only improves the operating efficiency of the power grid, but also provides support in peak load management, power outage management and energy use optimization. In addition, AMI has also promoted the application of technologies such as distributed energy and microgrids, making the access and utilization of renewable energy more flexible and intelligent. Therefore, AMI is of irreplaceable importance in the operation and maintenance of power systems and is a key link in realizing smart energy management.

[0003] With the widespread application of AMI in power systems, the importance of secure information transmission has become increasingly prominent. The AMI system needs to frequently transmit a large amount of user electricity consumption data, including sensitive information such as electricity usage habits and electricity consumption. Once tampered with or leaked, it will not only affect user privacy, but may also endanger the operational stability of the power system. What is more serious is that AMI connects a large number of power equipment and user terminals, becoming a potential entry point for network attacks, and therefore faces multiple threats including data tampering and malicious attacks. Effective information security transmission methods can ensure the integrity, confidentiality and availability of information, ensure the authenticity and real-time nature of information transmission, and prevent network attacks from damaging the power grid. It is an important guarantee for the stable and safe operation of the power system.

[0004] Traditional AMI information security transmission methods have great limitations when facing complex network attacks and changing security threats. They are difficult to effectively defend against 0Day attacks and have high resource consumption. Although intrinsic security has the advantages of autonomous defense and strong adaptability, its direct application in power systems faces problems such as high computing overhead and poor hardware compatibility. Summary of the invention

[0005] The present invention aims at the security issues such as data leakage, malicious attack and tampering faced in the process of AMI information transmission of power system, and provides a method for secure transmission of AMI information of power system based on improved intrinsic security. The method meets the high real-time and low power consumption requirements of power system for information transmission, can realize efficient and stable secure transmission of AMI information, and effectively ensure the overall security of the system.

[0006] The objective of the present invention is achieved through the following technical solutions:

[0007] A method for secure transmission of AMI information of a power system based on improved intrinsic safety comprises the following steps:

[0008] Step S1: The smart meter collects data, designs a message segmentation algorithm based on chaotic mapping, and uses this algorithm to segment the message M S Randomly divided into three sub-messages of different lengths M 1 , sub-message M 2 and sub-message M 3 , the specific steps are as follows:

[0009] Step S11: The smart meter collects data and sends the message M S Send to the message segmentation program and enter the message random segmentation stage;

[0010] Step S12: Determine the system parameters of the chaotic map: Set the initial value (x, y, z) of the parameter-transformed Lorenz chaotic map to (x 0 ,y 0 ,z 0 ), the parameters σ, ρ, β are set to σ=a·σ′+k σ ·Dσ、ρ=b·ρ′+k ρ ·Dρ,β=c·β′+k β Dβ, where (a, b, c) = (0, 1, 1), k σ =1,2,…,400,k ρ =0, k ρ =0;

[0011] Step S13: Establishing the boundless Markov random field of the message: S Convert to the corresponding hexadecimal ASCII code, and take a message byte as a node in the Markov random field. In order to ensure the randomness and unpredictability of node distribution, the three-dimensional coordinates of the node are obtained based on the Lorenz chaotic map of parameter transformation, and then the boundless Markov random field of the message is established;

[0012] Step S14: Calculate the potential function φ(i) of each node in the Markov random field = -log(P(x i )), where P(x i ) is the character x i The frequency of occurrence;

[0013] Step S15: Calculate the edge potential function ψ(i,j)=exp(-d(x i ,x j )), where d(x i ,xj )Node x i and node x j The distance between

[0014] Step S16: randomly grouping the nodes in the Markov random field: randomly assigning an initial group to each node, setting the total number of groups num_groups = m, and the number of nodes contained in each group group_size = n;

[0015] Step S17: Update group status: for node i, calculate the sum of its potential function value and edge potential function value under the current group to obtain the current energy current_energy; traverse all candidate groups g, calculate the energy difference energy_diff after node i moves to group g, which is the difference between the energy of node i under group g and the current energy; calculate the transition probability transition_prob based on the energy difference and perform normalization processing; sample and update the group, sample from the candidate groups according to the transition probability, and update the group status of node i;

[0016] Step S18: Repeat step S17 several times until the system reaches a stable distribution and obtains three sub-messages M 1 、M 2 and M 3 ;

[0017] Step S2: The smart meter uses a heterogeneous redundant encryption executor to encrypt the three sub-messages and message M S After processing, we get the three-part ciphertext SE 1 , SE 2 , SE 3 The sub-ciphertext and the message authentication code MAC are combined into an authentication encryption package AEP and sent to the data concentrator. The specific steps are as follows:

[0018] Step S21: message encryption operation: the smart meter converts the sub-message M 1 、M 2 and M 3 Send to the encryption execution body to perform encryption operation SE 1 =Symmetric_encrypt 1 (M 1 )、SE 2 =Symmetric_encrypt 2 (M 2 ) and SE 3 =Symmetric_encrypt 3 (M 3 ), and get the three-part ciphertext SE 1 , SE 2 and SE3 ;

[0019] Step S22: message authentication operation: the smart meter sends the message M S Send to the message authentication execution body, perform message authentication operation MAC = MAC (M S ), and obtain the message authentication code MAC;

[0020] Step S23: The smart meter sends the ternary ciphertext SE 1 , SE 2 and SE 3 and message authentication code MAC to form an authentication encryption package AEP and send the AEP to the data concentrator;

[0021] Step S3: The data concentrator decomposes AEP to obtain the three sub-ciphertexts SE 1 , SE 2 , SE 3 and the message authentication code MAC, and use the heterogeneous redundant decryption execution body to process the three sub-ciphertexts to obtain the three sub-messages M 1 、M 2 and M 3 , the specific steps are as follows:

[0022] Step S31: The data concentrator splits the received AEP to obtain three sub-ciphertexts SE 1 , SE 2 , SE 3 and message authentication code MAC;

[0023] Step S32: Decryption operation: The data concentrator converts the sub-ciphertext SE 1 , SE 2 and SE 3 Send to the decryption execution body to perform decryption operation M 1 =Symmetric_decrypt 1 (SE 1 )、M 2 =Symmetric_decrypt 2 (SE 2 ) and M 3 =Symmetric_decrypt 3 (SE 3 ), and get three sub-messages M 1 、M 2 and M 3 ;

[0024] Step S4: The data concentrator sends the sub-message M 1 、M 2 and M 3 Combined into unauthenticated message MR_unauthenticated , the message authentication function is used to authenticate the unauthenticated message M R_unauthenticated Process and get MAC 1 , MAC and MAC 1 Compare them. If they are the same, output the message. If they are different, it means that the information has been tampered with and resend the information. The specific steps are as follows:

[0025] Step S41: The data concentrator sends the sub-message M 1 、M 2 and M 3 Combined into unauthenticated message M R_unauthenticated ;

[0026] Step S42: Unauthenticated message authentication operation: The data concentrator converts the unauthenticated message M R_unauthenticated Send to the message authentication execution body, perform message authentication operation MAC = MAC (M R_unauthenticated ), get the message authentication code MAC of the unauthenticated message 1 ;

[0027] Step S43: The data concentrator compares the message authentication code MAC with the message authentication code MAC of the unauthenticated message. 1 Compare, if they are the same, output message M R =M R_unauthenticated If they are different, it means the information has been tampered with and you need to resend the information.

[0028] Compared with the prior art, the present invention has the following advantages:

[0029] 1. The present invention optimizes the inherent security mechanism to enable it to have stronger autonomous defense capabilities and resource efficiency, thereby better adapting to the power system's high real-time and low power consumption requirements for information transmission.

[0030] 2. Through the method of the present invention, the integrity, confidentiality and system stability of AMI data during transmission are effectively guaranteed, which significantly improves the information security level of the power system.

[0031] 3. Compared with the high resource consumption of traditional endogenous security protection measures, the method proposed in the present invention reduces the resource consumption of protection measures by introducing a message segmentation algorithm, meets the power system's requirements for real-time and low power consumption, and effectively ensures the security of AMI information transmission. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is an overall flow chart of the AMI information security transmission method for power systems based on improved intrinsic security;

[0033] Figure 2The present invention is a specific flow chart of the method for secure transmission of AMI information in power systems based on improved intrinsic safety. DETAILED DESCRIPTION

[0034] The technical solution of the present invention is further described below in conjunction with the accompanying drawings, but is not limited thereto. Any modification or equivalent replacement of the technical solution of the present invention without departing from the spirit and scope of the technical solution of the present invention should be included in the protection scope of the present invention.

[0035] The present invention provides a method for secure transmission of AMI information in a power system based on improved intrinsic safety, such as Figure 1 As shown, the method comprises the following steps:

[0036] Step S1: The smart meter collects data, designs a message segmentation algorithm based on chaotic mapping, and uses this algorithm to segment the message M S Randomly divided into three sub-messages of different lengths M 1 , sub-message M 2 and sub-message M 3 .

[0037] Step S2: The smart meter uses a heterogeneous redundant encryption executor to encrypt the three sub-messages and message M S After processing, we get the three-part ciphertext SE 1 , SE 2 , SE 3 The sub-ciphertext and the message authentication code MAC are combined into an authenticated encryption package AEP and sent to the data concentrator.

[0038] Step S3: The data concentrator decomposes AEP to obtain the three sub-ciphertexts SE 1 , SE 2 , SE 3 and the message authentication code MAC, and use the heterogeneous redundant decryption execution body to process the three sub-ciphertexts to obtain the three sub-messages M 1 、M 2 and M 3 .

[0039] Step S4: The data concentrator sends the sub-message M 1 、M 2 and M 3 Combined into unauthenticated message M R_unauthenticated , the message authentication function is used to authenticate the unauthenticated message M R_unauthenticated Process and get MAC 1 , MAC and MAC 1 Compare them, if they are the same, output the message, if they are different, it means the information has been tampered with and resend the information.

[0040] like Figure 2As shown, the specific implementation steps are as follows:

[0041] Step S1: The smart meter collects data and sends the message M S Send it to the message segmentation program and enter the random message segmentation stage.

[0042] Step S2: Determine the system parameters of the chaotic map. Set the initial value (x, y, z) of the parameter-transformed Lorenz chaotic map to (x 0 ,y 0 ,z 0 ) parameters σ, ρ, β are set to σ=a·σ′+k σ ·Dσ、ρ=b·ρ′+k ρ ·Dρ,β=c·β′+k β Dβ, where (a, b, c) = (0, 1, 1), k σ =1,2,…,400,k ρ =0, k ρ =0.

[0043] Step S3: Establish an infinite Markov random field of messages. S Convert to the corresponding hexadecimal ASCII code, and take a message byte as a node in the Markov random field. In order to ensure the randomness and unpredictability of node distribution, the three-dimensional coordinates of the node are obtained based on the Lorenz chaotic map with parameter transformation, and then the boundless Markov random field of the message is established.

[0044] Step S4: Calculate the potential function of each node in the Markov random field. The frequency-based potential function ensures that high-frequency characters have lower potential function values, so that these characters are more likely to keep their positions unchanged during the segmentation process, thereby reducing the frequent segmentation of high-frequency characters and maintaining the semantic structure and readability of the message. Therefore, the potential function of each node is φ(i) = -log(P(x i )), where P(x i ) is the character x i The frequency of occurrence.

[0045] Step S5: Calculate the edge potential function between nodes in the Markov random field. The distance-based edge potential function quantifies the spatial distance between nodes to ensure that characters with closer distances are more likely to be assigned to the same group. This method utilizes the spatial correlation between characters, increases the rationality of segmentation, and ensures the consistency of message segmentation results in space. Therefore, the edge potential function between nodes is ψ(i,j)=exp(-d(x i ,x j )), where d(x i ,x j )Node x iand node x j The distance between.

[0046] Step S6: Randomly group the nodes in the Markov random field. Randomly assign an initial group to each node, set the total number of groups num_groups = m, and the number of nodes in each group group_size = n.

[0047] Step S7: Update the group status. For node i, calculate the sum of its potential function value and edge potential function value under the current group to obtain the current energy current_energy. Traverse all candidate groups g and calculate the energy difference energy_diff after node i moves to group g. The energy difference is the difference between the energy of node i under group g and the current energy. Calculate the transition probability transition_prob based on the energy difference. The transition probability is proportional to the negative exponent of the energy difference and is normalized. Sample and update the group. According to the transition probability, sample from the candidate group and update the group status of node i.

[0048] Step S8: Repeat step S7 several times until the system reaches a stable distribution and obtains three sub-messages M 1 、M 2 and M 3 .

[0049] Step S9: message encryption operation. The smart meter converts the sub-message M 1 、M 2 and M 3 Send to the encryption execution body to perform encryption operation SE 1 =Symmetric_encrypt 1 (M 1 )、SE 2 =Symmetric_encrypt 2 (M 2 ) and SE 3 =Symmetric_encrypt 3 (M 3 ), and get the three-part ciphertext SE 1 , SE 2 and SE 3 .

[0050] Step S10: message authentication operation. The smart meter sends the message M S Send to the message authentication execution body, perform message authentication operation MAC = MAC (M S ) and get the message authentication code MAC.

[0051] Step S11: The smart meter sends the tripartite ciphertext SE 1 , SE2 and SE 3 and message authentication code MAC are combined into an authentication encryption package AEP and the AEP is sent to the data concentrator.

[0052] Step S12: The data concentrator splits the received AEP to obtain three sub-ciphertexts SE 1 , SE 2 , SE 3 And message authentication code MAC.

[0053] Step S13: Decryption operation. The data concentrator converts the sub-ciphertext SE 1 , SE 2 and SE 3 Send to the decryption execution body to perform decryption operation M 1 =Symmetric_decrypt 1 (SE 1 )、M 2 =Symmetric_decrypt 2 (SE 2 ) and M 3 =Symmetric_decrypt 3 (SE 3 ), and get three sub-messages M 1 、M 2 and M 3 .

[0054] Step S14: The data concentrator sends the sub-message M 1 、M 2 and M 3 Combined into unauthenticated message M R_unauthenticated .

[0055] Step S15: Authentication operation of unauthenticated message. R_unauthenticated Send to the message authentication execution body, perform message authentication operation MAC = MAC (M R_unauthenticated ) Get the message authentication code MAC of the unauthenticated message 1 .

[0056] Step S16: The data concentrator compares the message authentication code MAC with the message authentication code MAC of the unauthenticated message. 1 Compare, if they are the same, output message M R =M R_unauthenticated , if they are different, it means the information has been tampered with and you need to resend the information.

Claims

1. A method for secure transmission of AMI information in a power system based on improved intrinsic safety, characterized in that The method comprises the following steps: Step S1: The smart meter collects data, designs a message segmentation algorithm based on chaotic mapping, and uses this algorithm to segment the message M S Randomly divide into three sub-messages M1, M2 and M3 of different lengths; Step S2: The smart meter uses a heterogeneous redundant encryption executor to encrypt the three sub-messages and message M S After processing, three sub-ciphertexts SE1, SE2, SE3 and a message authentication code MAC are obtained, and the sub-ciphertexts and the message authentication code are combined into an authenticated encryption package AEP and sent to the data concentrator; Step S3: The data concentrator decomposes the AEP to obtain three sub-ciphertexts SE1, SE2, SE3 and a message authentication code MAC, and uses a heterogeneous redundant decryption executive to process the three sub-ciphertexts to obtain three sub-messages M1, M2 and M3; Step S4: The data concentrator combines sub-messages M1, M2 and M3 into an unauthenticated message M R_unauthenticated , the message authentication function is used to authenticate the unauthenticated message M R_unauthenticated Process and obtain MAC1, compare MAC with MAC1, if they are the same, output the message, if they are different, it means that the information has been tampered with and resend the information.

2. The method for secure transmission of AMI information in a power system based on improved intrinsic safety according to claim 1 is characterized in that The specific steps of step S1 are as follows: Step S11: The smart meter collects data and sends the message M S Send to the message segmentation program and enter the message random segmentation stage; Step S12: Determine the system parameters of the chaotic map: set the initial value (x, y, z) of the parameter-transformed Lorenz chaotic map to (x0, y0, z0), and set the parameters σ, ρ, and β to σ = a·σ′+k σ ·Dσ、ρ=b·ρ′+k ρ ·Dρ,β=c·β′+k β Dβ, where (a, b, c) = (0, 1, 1), k σ =1,2,…,400,k ρ =0, k ρ =0; Step S13: Establishing the boundless Markov random field of the message: S Convert to the corresponding hexadecimal ASCII code, and take a message byte as a node in the Markov random field. In order to ensure the randomness and unpredictability of node distribution, the three-dimensional coordinates of the node are obtained based on the Lorenz chaotic map of parameter transformation, and then the boundless Markov random field of the message is established; Step S14: Calculate the potential function φ(i) of each node in the Markov random field = -log(P(x i )), where P(x i ) is the character x i The frequency of occurrence; Step S15: Calculate the edge potential function ψ(i,j)=exp(-d(x i ,x j )), where d(x i ,x j )Node x i and node x j The distance between Step S16: randomly grouping the nodes in the Markov random field: randomly assigning an initial group to each node, setting the total number of groups num_groups = m, and the number of nodes contained in each group group_size = n; Step S17: Update group status: for node i, calculate the sum of its potential function value and edge potential function value under the current group to obtain the current energy current_energy; traverse all candidate groups g, calculate the energy difference energy_diff after node i moves to group g, which is the difference between the energy of node i under group g and the current energy; calculate the transition probability transition_prob based on the energy difference and perform normalization processing; sample and update the group, sample from the candidate groups according to the transition probability, and update the group status of node i; Step S18: Repeat step S17 several times until the system reaches a stable distribution and obtains three sub-messages M1, M2 and M3.

3. The method for secure transmission of AMI information in a power system based on improved intrinsic safety according to claim 1 is characterized in that The specific steps of step S2 are as follows: Step S21: message encryption operation: the smart meter sends the sub-messages M1, M2 and M3 to the encryption execution body, performs encryption operations SE1=Symmetric_encrypt1(M1), SE2=Symmetric_encrypt2(M2) and SE3=Symmetric_encrypt3(M3), and obtains three sub-ciphertexts SE1, SE2 and SE3; Step S22: message authentication operation: the smart meter sends the message M S Send to the message authentication execution body, perform message authentication operation MAC = MAC (M S ), and obtain the message authentication code MAC; Step S23: The smart meter combines the three sub-ciphertexts SE1, SE2 and SE3 and the message authentication code MAC into an authentication encryption package AEP and sends the AEP to the data concentrator.

4. The method for secure transmission of AMI information in a power system based on improved intrinsic safety according to claim 1 is characterized in that The specific steps of step S3 are as follows: Step S31: The data concentrator splits the received AEP to obtain three sub-ciphertexts SE1, SE2, SE3 and a message authentication code MAC; Step S32: Decryption operation: The data concentrator sends the sub-ciphertexts SE1, SE2 and SE3 to the decryption execution body, performs decryption operations M1=Symmetric_decrypt1(SE1), M2=Symmetric_decrypt2(SE2) and M3=Symmetric_decrypt3(SE3), and obtains three sub-messages M1, M2 and M3.

5. The method for secure transmission of AMI information in a power system based on improved intrinsic safety according to claim 1 is characterized in that The specific steps of step S4 are as follows: Step S41: The data concentrator combines sub-messages M1, M2 and M3 into an unauthenticated message M R_unauthenticated ; Step S42: Unauthenticated message authentication operation: The data concentrator converts the unauthenticated message M R_unauthenticated Send to the message authentication execution body, perform message authentication operation MAC = MAC (M R_unauthenticated ), obtain the message authentication code MAC1 of the unauthenticated message; Step S43: The data concentrator compares the message authentication code MAC with the message authentication code MAC1 of the unauthenticated message, and outputs the message M if they are the same. R =M R_unauthenticated If they are different, it means the information has been tampered with and you need to resend the information.

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