Equipment message mutual access application system based on 5GLAN static multicast

Abstract

The invention discloses an equipment message mutual access application system based on 5GLAN static multicast, and relates to the technical field of communication. A 5GLAN network is constructed in a coverage area of a smart power grid, static multicast groups are divided according to a distribution area and management membership of smart electric meters, and the static multicast groups are distributed according to the distribution area and the management membership of the smart electric meters; the control center transmits a meter reading instruction and a digital certificate of the control center to the static multicast group, the static multicast group respectively selects digital certificate verification, equipment number verification, equipment membership verification and instruction frequency verification according to the level of the control center to carry out combined verification, if the verification is successful, the identity of the control center is passed, otherwise, the control center does not receive the instruction, and the static multicast group does not receive the instruction. And after the intelligent electric meter and the concentrator receive the instruction, the concentrator acquires related data, performs identity verification on the static multicast group before transmission, and performs lossless compression on encrypted data and transmits the compressed encrypted data to the static multicast group if the data succeeds in transmission. According to the invention, the data acquisition efficiency of the intelligent electric meter is improved, and the data transmission safety and integrity of the intelligent electric meter are effectively guaranteed.

Description

Technical Field

[0001] The present invention relates to the field of communication technology, and in particular to a device message mutual access application system based on 5GLAN static multicast. Background Art

[0002] With the continuous advancement of smart grid development, a large number of smart meters are connected to the network to achieve data interaction and management. Although the technical solution of connecting many smart meters using 5GLAN, static multicast groups and control centers has certain advantages, it also has many problems.

[0003] In terms of identity authentication, the identity authentication system in existing technologies is not perfect. Unauthorized access to static multicast groups to obtain smart meter data leads to the leakage of user electricity usage information, which not only infringes on user privacy but may also cause problems such as abnormal electricity bills.

[0004] In terms of data transmission efficiency, when many smart meters transmit data to the multicast group simultaneously, there is a lack of an effective scheduling mechanism. For example, during peak electricity consumption periods, a large number of smart meters upload data simultaneously, causing network congestion and severe data transmission delays. In addition, the control center spends a lot of time collecting data and is unable to obtain electricity consumption data in a timely and accurate manner, which affects the power company's real-time monitoring and scheduling of grid loads and reduces the stability of power supply.

[0005] The ability to respond to network failures is poor. When a 5GLAN network fails, smart meters lack a reliable data caching mechanism. Some smart meters only have a small amount of temporary cache space. Once the network failure lasts for a while, the newly generated smart meter data will be lost. After the network connection is restored, the missing data cannot be supplemented, resulting in incomplete power data, affecting the accuracy of power data analysis. These problems seriously restrict the efficient and safe operation of smart grids and urgently need more complete technical solutions to solve them. Summary of the Invention

[0006] In response to the shortcomings of the existing technology, the present invention provides a device message mutual access application system based on 5GLAN static multicast, which solves the problems of easy leakage, low efficiency and easy data loss in the data transmission process of many smart meters during failure.

[0007] To achieve the above objectives, the present invention is implemented through the following technical solutions: a device message mutual access application system based on 5GLAN static multicast, comprising: The instruction generation and transmission module generates meter reading instructions for different smart meters through the control center and transmits its own digital certificate and meter reading instructions to the instruction receiving and processing module; The command receiving and processing module divides the control center into low, medium, and high risks based on network delay, packet loss rate, and time deviation amplitude. For low risk, digital certificate verification is used; for medium risk, digital certificate verification, device number verification, and device affiliation verification are used; for high risk, digital certificate verification, device number verification, device affiliation verification, and command frequency verification are used; The data return module pre-assigns a unique pre-shared key (PSK) to the concentrator and the corresponding static multicast group. Before the concentrator transmits data to the static multicast group, it will issue a historical data return instruction to the static multicast group and transmit the encrypted instruction to the static multicast group. After obtaining the encrypted instruction, the static multicast group uses the PSK to decrypt it and returns the answer to the concentrator. The concentrator matches the decrypted data with the cached data. If successful, the concentrator will losslessly compress the encrypted data and transmit it to the static multicast group. Otherwise, the identity of the static multicast group is judged to be suspicious and the data will not be transmitted.

[0008] As a further solution of the present invention, it also includes a network multicast configuration module and a data receiving module; The network multicast configuration module builds a 5GLAN network in the smart grid coverage area. When dividing static multicast groups, the smart meters are grouped according to their distribution area and management affiliation. The control center and concentrator responsible for smart meter data management in the area are added to the communication system corresponding to the smart meter group. During the equipment installation phase, the 5GLAN communication module and related parameters are configured for each smart meter and concentrator. After the configuration is completed, the network connection of the device is fully tested using professional network testing tools to ensure that it can stably access the 5GLAN network and successfully join the corresponding static multicast group. The data receiving module receives the data transmitted by the concentrator through the static multicast group, unpacks and decompresses it, restores the original size of the data, and decrypts the data using PSK to obtain the original smart meter data. The control center maintains close communication with the static multicast group to ensure that the original smart meter data can be quickly obtained after decryption is completed.

[0009] As a further solution of the present invention, the specific steps of classifying the instruction sending time into different levels according to the time deviation amplitude are as follows: Set the normal business time interval to [t1, t2]; The time range of a day is divided into [0,24), and the intervals outside normal business hours are [0,t1) and (t2,24); If t∈[0,t1), the most recent deviation time is min{t1-t,t+24-t2}, and the deviation amplitude miu=min{t1-t,t+24-t2} / t1+24-t2 is calculated based on the most recent deviation time; If \(t\in(t_2, 24)\), the recent deviation time is \(\min\{t - t_2, t_1 + 24 - t\}\), and the deviation amplitude \(\mu=\frac{\min\{t - t_2, t_1 + 24 - t\}}{t_1 + 24 - t_2}\) is calculated based on the recent deviation time. If \(\mu<\mu_1\), it is recorded as a third-level deviation; if \(\mu_1\leqslant\mu\leqslant\mu_2\), it is recorded as a second-level deviation; if \(\mu>\mu_2\), it is recorded as a first-level deviation, where \(\mu_1\) and \(\mu_2\) are amplitude thresholds.

[0010] As a further aspect of the present invention, the specific method for marking the control center level according to network delay, packet loss rate, and time deviation level is as follows: If the network delay \(\leqslant a_1\) and the packet loss rate \(\leqslant b_1\), and the sending time deviation level is the third level, the control center is marked as low risk; If \(a_1 <\) network delay \(\leqslant a_2\) or \(b_1 <\) packet loss rate \(\leqslant b_2\), the sending time deviation level is the third level, or the network delay \(\leqslant a_1\) and the packet loss rate \(\leqslant b_1\), and the sending time deviation level is the second level, the control center is marked as medium risk; If the network delay \(> a_2\) or the packet loss rate \(> b_2\) or the sending time deviation level is the first level, the control center is marked as high risk, where \(a_1\), \(a_2\), \(b_1\), and \(b_2\) are control thresholds.

[0011] As a further aspect of the present invention, each concentrator corresponds to a specific group of smart meters. The numbers of the meters in the group of smart meters have a subordination relationship with the concentrator number, and the group of smart meters represents a number of smart meters collected by the concentrator.

[0012] As a further aspect of the present invention, a frequency threshold for the control center to send instructions to the static multicast group is predefined. If the predefined frequency threshold is exceeded, it indicates that the current control center is abnormal or an attacker is attempting to break through the authentication, and the static multicast group will determine that the identity of the control center is suspicious.

[0013] As a further aspect of the present invention, the concentrator sends a historical data feedback instruction to the static multicast group. The historical data feedback instruction is specifically the smart meter data that the concentrator has historically transmitted to the corresponding static multicast group. The smart meter data is temporarily cached in the static multicast group and each corresponds to a different timestamp, and the corresponding meter data is retrieved according to the timestamp.

[0014] As a further solution of the present invention, when the concentrator receives an instruction from the control center to collect meter data for a specific time period, the concentrator will extract the time period in the instruction and compare it with the time period of the data cached by itself. If they match, the concentrator will directly extract the relevant data from the cache for processing and return. Otherwise, after receiving the instruction, the concentrator will interrupt the currently executing routine task and immediately establish a connection with the corresponding meter group to collect data.

[0015] As a further solution of the present invention, the static multicast group encrypts and encapsulates the command answer and transmits it back to the concentrator. If the return time exceeds the specified time threshold, the static multicast group is judged to be suspicious and the data is not transmitted.

[0016] As a further solution of the present invention, data transmission between the static multicast group and the concentrator is encrypted using AES, and the specific algorithm used by the concentrator to losslessly compress the encrypted data is the Zlib algorithm.

[0017] The present invention provides a device message mutual access application system based on 5GLAN static multicast, which has the following advantages compared with the existing technology: (1) The present invention builds an efficient data collection link by deploying a concentrator to collect data from each smart meter. The control center only needs to locate the concentrator of the static multicast group to obtain data, without having to directly interact with a large number of smart meters one by one, thereby improving the efficiency of smart meter data acquisition. At the same time, the concentrator has a certain data caching capability. When the network is interrupted, it can temporarily store smart meter data, effectively preventing smart meter data loss due to network failure. (2) The present invention effectively ensures the security and integrity of smart meter data transmission by constructing a multiple authentication mechanism among the control center, static multicast group, and concentrator, and also involves data encryption and compression technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a block diagram of the system principle of the present invention. DETAILED DESCRIPTION

[0019] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0020] like Figure 1 , this application provides a device message mutual access application system based on 5GLAN static multicast, including: The network multicast configuration module builds a 5G LAN network in the smart grid coverage area, deploys 5G base stations and related communication equipment, and ensures stable and high-speed 5G LAN signal coverage at the location of smart meters, providing a basic network environment for subsequent communications. When building a 5G LAN network, consider a large urban smart grid covering 5 square kilometers. This urban area, with its numerous high-rise buildings and underground facilities, severely hinders 5G signal propagation. To achieve comprehensive 5G LAN network coverage in the urban area, in addition to requiring a professional technical team, the site selection and layout of 5G base stations must be scientifically planned based on the urban terrain and the distribution of smart meters. In areas with dense high-rise buildings, base station transmit power can be increased, and beamforming technology can be used to ensure precise signal coverage of smart meters. This ensures that signal strength meets the requirements for stable communication between the concentrator and smart meters, and that network transmission latency is kept within a reasonable range that does not affect data recording and interaction. When creating static multicast groups, group smart meters based on their distribution area and management affiliation. For example, all smart meters in a street can be grouped as "Street X Smart Meter Group," assigned the multicast IP address 239.50.50.50, and the control center and concentrator responsible for managing smart meter data in that area can be added to the communication system corresponding to this smart meter group. The concentrator is an important hub connecting smart meters and the control center. Its primary task is to collect data from each smart meter. The concentrator will proactively send data collection instructions to the smart meters in its area of ​​responsibility at preset time intervals. After collecting data, the concentrator will summarize these scattered data into a complete file to facilitate subsequent processing and transmission. During this process, when there is a network failure or congestion, the concentrator can temporarily store the collected smart meter data in a local large-capacity storage device to avoid data loss. For example, during a brief network outage caused by a community network upgrade, the concentrator will completely cache the smart meter data collected for several hours and upload the data accurately after the network is restored. The concentrator can also use built-in data analysis algorithms to conduct preliminary analysis of smart meter data and diagnose potential faults in advance. For example, by monitoring fluctuations in voltage and current data, it can determine whether the smart meter has abnormal measurement or line faults. If the voltage data of a smart meter is found to be continuously outside the normal range, the concentrator will transmit this fault information along with other data of the smart meter to the static multicast group; During the equipment installation phase, a 5GLAN communication module and related parameters are configured for each smart meter and concentrator. For a newly added smart meter, for example, technicians need to accurately enter the multicast IP address, subnet mask, gateway, and other information of the static multicast group on the smart meter's setup interface. After configuration is complete, a professional network testing tool is used to thoroughly test the device's network connection to ensure stable access to the 5GLAN network and successful joining of the "Street X Smart Meter Group."

[0021] The instruction generation and transmission module generates meter reading instructions for different smart meter groups through the control center, and transmits its own digital certificate and meter reading instructions to the instruction receiving and processing module; The control center's meter reading instructions take into account multiple factors, such as the location and type of smart meters, to determine the group of smart meters that need to record data. For example, for the "street x smart meter group" example, the instructions not only include specific meter reading requirements, such as reading monthly electricity consumption, daily peak and valley values, but also include a precise timestamp to record the exact time the instruction was generated, facilitating subsequent traceability and data management. After encapsulating the control center's digital certificate and meter reading instructions according to the 5GLAN communication protocol, a static multicast group address needs to be added to the message header. For example, the multicast IP address corresponding to the smart meter group in this area is 239.50.50.50, which clearly indicates that the instruction is sent to all smart meters and related concentrators in the "street X smart meter group"; The high speed and low latency of the 5GLAN network allow commands to quickly enter the network transmission channel. Ideally, the time interval from when the control center sends the command to when the smart meter and concentrator receive the command is extremely short, ensuring that the meter reading command can be transmitted in a timely manner.

[0022] The command receiving and processing module selects different verification methods by monitoring the network and recording the time of the control center's commands to ensure the security and accuracy of smart meter data recording; When the control center sends a meter reading command to the "street X smart meter group," the command first reaches the corresponding static multicast group. After the static multicast group receives the command, network monitoring tools are used to obtain two key indicators: network latency and packet loss rate. Network latency refers to the time it takes from the control center sending the command to the static multicast group receiving it. The packet loss rate refers to the proportion of lost packets among the sent packets. At the same time, the specific time of each command sent by the control center must be recorded. The static multicast group can maintain a log file that records the sending time of each command to the second and compares it with the pre-set normal business time interval [t1, t2]. The normal business time interval [t1, t2] is determined according to the actual business requirements and operation rules of the system. For example, for the control center of a power system, the normal business time may be set as 9:00 - 17:00 on weekdays, that is, t1 = 9 and t2 = 17; The time range of a day is divided into [0, 24). The intervals outside the normal business time are [0, t1) and (t2, 24). According to the interval where the instruction sending time t is located, calculate the nearest deviation time and deviation amplitude: If t ∈ [0, t1), the nearest deviation time is min{t1 - t, t + 24 - t2}. For example, when t1 = 9, t2 = 17, and the instruction sending time t = 3, t1 - t = 9 - 3 = 6, t + 24 - t2 = 3 + 24 - 17 = 10, then the nearest deviation time is min{6, 10} = 6; Calculate the deviation amplitude miu = min{t1 - t, t + 24 - t2} / (t1 + 24 - t2). In the above example, t1 + 24 - t2 = 9 + 24 - 17 = 16, so miu = 6 / 16 = 0.375; If t ∈ (t2, 24), the nearest deviation time is min{t - t2, t1 + 24 - t}. For example, when t = 20, t - t2 = 20 - 17 = 3, t1 + 24 - t = 9 + 24 - 20 = 13, then the nearest deviation time is min{3, 13} = 3; The deviation amplitude miu = min{t - t2, t1 + 24 - t} / (t1 + 24 - t2). Here miu = 3 / 16 = 0.1875; According to the calculated deviation amplitude miu, compare it with the pre-set thresholds miu1 and miu2, where miu1 < miu2, and divide the deviation levels: If miu < miu1, it is recorded as a level-three deviation, indicating that the deviation degree of the instruction sending time from the normal business time is relatively small and the risk is relatively low. For example, if miu1 = 0.2 and miu = 0.1875, it belongs to a level-three deviation; If miu1 <= miu <= miu2, it is recorded as a level-two deviation, with a moderate deviation degree and certain risks; If miu > miu2, it is recorded as a level-one deviation, indicating that the deviation degree of the instruction sending time from the normal business time is relatively large, there may be abnormal situations, and the risk is relatively high. For example, if miu2 = 0.5 and miu = 0.6, it belongs to a level-one deviation; According to the network delay, packet loss rate, and time deviation level, formulate the verification level division rules: If the network delay is less than or equal to a1 and the packet loss rate is less than or equal to b1, and the sending time deviation level is level 3, this means that the network condition is good, the deviation between the instruction sending time and normal business hours is small, and the risk faced by the system is low, so it is marked as low risk; For control centers marked as low-risk, only the control center's digital certificate needs to be verified. The signature of the control center's digital certificate is decrypted using the pre-stored CA public key and compared in detail with the original information in the certificate to check the integrity and authenticity of the certificate. At the same time, the static multicast group also checks the certificate validity period and whether the control center name is consistent with the system records. Only after the digital certificate verification steps are successfully passed, the verification is considered passed. If a1 < network delay <= a2 or b1 < packet loss rate <= b2, the sending time deviation level is level 3; or if network delay <= a1 and packet loss rate <= b1, the sending time deviation level is level 2, then it is marked as medium risk; For control centers marked as medium risk, the first task is to verify the control center's digital certificate. If the verification passes, the device number verification process will proceed as follows: The static multicast group extracts the numbers of the concentrator and each smart meter from the command and checks them against the numbers of all associated devices stored in its own storage. Each concentrator and smart meter has a unique number. The static multicast group stores complete number information. It will carefully compare the number in the command with the number stored in its own storage to see if it matches. If the number verification passes, it means that the device number in the command is consistent with the system record, and then proceed to the next step of device affiliation verification. If the verification passes, it continues to device affiliation verification: The static multicast group extracts the affiliation information between the concentrator and the smart meter group from the command sent by the control center. In the smart grid system, each concentrator corresponds to a specific smart meter group, and this affiliation is also clearly recorded in the static multicast group. If the affiliation in the command matches the affiliation stored in the static multicast group, the verification is successful. Otherwise, the control center is considered suspicious. For example, concentrator A is numbered C001. The smart meters in smart meter group X on street X are numbered M001-M1000, and the smart meters in smart meter group Y on street Y are numbered N001-N1000. Based on the command information sent by the control center, the control center extracts numbers C001, M001-M1000, and N001-N100. The static multicast group compares these numbers with its own stored numbers and finds a match. The process then proceeds to device affiliation verification. Based on the affiliation relationships between devices in the static multicast group, concentrator C001 can only collect data from M001-M1000, i.e., smart meter group X on street X. Data from N001-N100 cannot be collected by C001, indicating that there is no affiliation relationship between the two. Therefore, the control center's identity is considered suspicious. If the network delay is greater than a2, the packet loss rate is greater than b2, or the sending time deviation level is level 1, it is marked as high risk; For control centers marked as high-risk, digital certificate verification, device number verification, and device affiliation verification are performed one by one. If any of these verifications fail, the control center's identity is considered suspicious. Finally, command frequency verification is required. Based on actual business needs, a frequency threshold for the control center to send commands to the "street X smart meter group" is set. Exceeding the specified frequency threshold indicates that the current control center is abnormal or an attacker is attempting to break through identity verification. For example, under normal circumstances, the control center must not send more than 30 adjustment commands to the group of devices per hour. If the static multicast group receives 35 commands within an hour, the static multicast group will determine the control center's identity is suspicious, indicating abnormal operation or malicious attack, and timely preventive measures will be taken. If the control centers marked as low, medium, or high risk all pass verification, the static multicast group will forward the control center's instructions to the concentrators and smart meters within the group. After receiving the instructions, the concentrators and smart meters will decapsulate and parse them. Based on the parsed instructions, the smart meters will read their own recorded smart meter data, such as monthly electricity consumption, voltage and current data at different time periods, and transmit this data to the concentrator. If the concentrator collects data at fixed intervals and has already collected and cached data within the specified time period when it receives a command, the concentrator can directly extract the relevant data from the cache for processing. For example, the concentrator collects smart meter data every 15 minutes. The control center requires the collection of smart meter data within the past 10-20 minutes. The concentrator just completed data collection 10 minutes ago. At this time, it only needs to filter out the 10-20 minute portion from the cache for subsequent processing. This can improve data acquisition efficiency and reduce unnecessary communication overhead and device resource consumption.

[0023] Data return module, which ensures the reliability and efficiency of smart meter data return through strict security mechanisms and efficient data processing processes; The concentrator and the corresponding static multicast group are pre-assigned a unique pre-shared key (PSK), which is distributed through a secure offline channel and stored in the secure storage modules of the concentrator and the static multicast group respectively. Before the concentrator transmits the collected smart meter data to the static multicast group, it needs to use PSK to authenticate the static multicast group to ensure data security and accuracy; The concentrator sends a historical data return instruction to the static multicast group, encrypts and encapsulates the instruction using PSK, and transmits it to the static multicast group via 5GLAN. The historical data transmission instructions mentioned above mainly include the smart meter data that the concentrator has historically transmitted to the static multicast group. Because both the static multicast group and the concentrator can store historical smart meter data, identity verification can be achieved by verifying the historical data of both. After receiving the encrypted instruction, the static multicast group uses the same PSK to decrypt it, encrypts and encapsulates the instruction answer, and then sends it back to the concentrator. If the return time exceeds the specified time threshold, the static multicast group identity is judged to be suspicious. If the return time is within the specified time threshold, the concentrator uses PSK to decrypt again and compares the decrypted data with its own cached data one by one. If the match is successful, the identity authentication is successful. Otherwise, the static multicast group identity is judged to be suspicious. For example, the concentrator stores the smart meter data transmitted to the static multicast group within the past time T in the cache. At this time, in order to verify the identity of the static multicast group, the concentrator sends the "smart meter data within the past time T" instruction to the static multicast group. This instruction will be encrypted using PSK. If the decryption time of the static multicast group is within the time threshold and the returned smart meter data is consistent, the static multicast group identity authentication is successful; otherwise, the identity authentication fails. After receiving the data returned by the static multicast group, the timestamp, data value and other information of each record are compared one by one. If the comparison is consistent, the identity authentication of both parties is successful; otherwise, the identity authentication fails. The data obtained by the concentrator is encrypted using the AES algorithm, which has high encryption strength and efficiency. The encrypted data is then losslessly compressed. For example, the Zlib algorithm is used for lossless compression, with a compression ratio of over 70%, effectively reducing the amount of data transmitted. The compressed data is encapsulated according to the 5GLAN communication protocol, and the target static multicast group address is added to the message header. At this time, the static multicast group includes the control center, indicating that the data is sent back to them.

[0024] Data receiving module, which receives smart meter data by continuously monitoring the corresponding multicast address, decrypts the data using the pre-shared key, verifies the integrity and accuracy of the data, and filters out valid data; After receiving the data transmitted by the concentrator, the static multicast group first decapsulates it, then decompresses it using the same compression algorithm to restore the original size of the data. Finally, it decrypts the data using the shared key to obtain the smart meter data transmitted by the concentrator, such as the real-time power consumption, voltage, current of each smart meter, and abnormal information initially processed by the concentrator. The control center maintains close communication with the static multicast group and can quickly and accurately obtain the decrypted smart meter data from the static multicast group. The control center uses data analysis tools to conduct in-depth mining and analysis of the smart meter data. For example, by analyzing electricity consumption in different time periods, the control center can determine the peak and trough periods of residents' electricity consumption, providing a basis for power dispatch. It can also compare the data of each smart meter to detect abnormal electricity consumption and ensure the stable and efficient operation of the power system.

[0025] Some of the data in the above formulas are dimensionless and numerically calculated. Meanwhile, the contents not described in detail in this specification belong to the prior art known to those skilled in the art.

[0026] The above embodiments are only used to illustrate the technical method of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical method of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical method of the present invention.

Claims

1. The device message mutual access application system based on 5GLAN static multicast is characterized by: include: The instruction generation and transmission module generates meter reading instructions for different smart meters through the control center and transmits its own digital certificate and meter reading instructions to the instruction receiving and processing module; The command receiving and processing module divides the control center into low, medium, and high risks based on network delay, packet loss rate, and time deviation amplitude. For low risk, digital certificate verification is used; for medium risk, digital certificate verification, device number verification, and device affiliation verification are used; for high risk, digital certificate verification, device number verification, device affiliation verification, and command frequency verification are used; The data return module pre-assigns a unique pre-shared key (PSK) to the concentrator and the corresponding static multicast group. Before the concentrator transmits data to the static multicast group, it will issue a historical data return instruction to the static multicast group and transmit the encrypted instruction to the static multicast group. After obtaining the encrypted instruction, the static multicast group uses the PSK to decrypt it and returns the answer to the concentrator. The concentrator matches the decrypted data with the cached data. If successful, the concentrator will losslessly compress the encrypted data and transmit it to the static multicast group. Otherwise, the identity of the static multicast group is judged to be suspicious and the data will not be transmitted.

2. The device message mutual access application system based on 5GLAN static multicast according to claim 1 is characterized in that: It also includes a network multicast configuration module and a data receiving module; The network multicast configuration module builds a 5GLAN network in the smart grid coverage area. When dividing static multicast groups, the smart meters are grouped according to their distribution area and management affiliation. The control center and concentrator responsible for smart meter data management in the area are added to the communication system corresponding to the smart meter group. During the equipment installation phase, the 5GLAN communication module and related parameters are configured for each smart meter and concentrator. After the configuration is completed, the network connection of the device is fully tested using professional network testing tools to ensure that it can stably access the 5GLAN network and successfully join the corresponding static multicast group. The data receiving module receives the data transmitted by the concentrator through the static multicast group, unpacks and decompresses it, restores the original size of the data, and decrypts the data using PSK to obtain the original smart meter data. The control center maintains close communication with the static multicast group to ensure that the original smart meter data can be quickly obtained after decryption is completed.

3. The device message mutual access application system based on 5GLAN static multicast according to claim 1 is characterized in that: The specific steps for classifying instruction sending time into different levels according to the time deviation are as follows: Set the normal business time interval to [t1, t2]; The time range of a day is divided into [0,24), and the intervals outside normal business hours are [0,t1) and (t2,24); If t∈[0,t1), the most recent deviation time is min{t1-t,t+24-t2}, and the deviation amplitude miu=min{t1-t,t+24-t2} / t1+24-t2 is calculated based on the most recent deviation time; If t∈(t2,24), the most recent deviation time is min{t-t2,t1+24-t}, and the deviation amplitude miu=min{t-t2,t1+24-t} / t1+24-t2 is calculated based on the most recent deviation time; If μ < μ1, it is recorded as a third-level deviation. If μ1 <= μ <= μ2, it is recorded as a second-level deviation. If μ > μ2, it is recorded as a first-level deviation. Here, μ1 and μ2 are amplitude thresholds.

4. The device message mutual access application system based on 5GLAN static multicast according to claim 1 is characterized in that: The specific method for marking the control center level according to network latency, packet loss rate, and time deviation level is as follows: If the network latency <= a1 and the packet loss rate <= b1, and the sending time deviation level is the third level, then the control center is marked as low risk. If a1 < network latency <= a2 or b1 < packet loss rate <= b2, the sending time deviation level is the third level, or the network latency <= a1 and the packet loss rate <= b1, and the sending time deviation level is the second level, then the control center is marked as medium risk. If the network latency > a2 or the packet loss rate > b2, or the sending time deviation level is the first level, then the control center is marked as high risk. Here, a1, a2, b1, and b2 are control thresholds.

5. The device message mutual access application system based on 5GLAN static multicast according to claim 1 is characterized in that: Each concentrator corresponds to a specific group of smart meters. The numbers of the meters in the smart meter group have a subordination relationship with the concentrator number. The smart meter group represents a number of smart meters collected by this concentrator.

6. The device message mutual access application system based on 5GLAN static multicast according to claim 1 is characterized in that: A frequency threshold for the control center to send instructions to the static multicast group is predefined. If it exceeds the predefined frequency threshold, it indicates that the current control center is abnormal or an attacker is attempting to break through the authentication. The static multicast group will determine that the identity of the control center is suspicious.

7. The device message mutual access application system based on 5GLAN static multicast according to claim 1 is characterized in that: The concentrator will send a historical data feedback instruction to the static multicast group. The historical data feedback instruction is specifically the smart meter data that the concentrator has historically transmitted to the corresponding static multicast group. This smart meter data is temporarily cached in the static multicast group, and each corresponds to a different timestamp, and the corresponding meter data can be retrieved according to the timestamp.

8. The device message mutual access application system based on 5GLAN static multicast according to claim 1 is characterized in that: When the concentrator receives an instruction from the control center to collect meter data for a specific period, the concentrator will extract the period in the instruction and compare it with the period of the data cached by itself. If they match, it will directly extract the relevant data from the cache for processing and feedback. Otherwise, after receiving the instruction, the concentrator will interrupt the regular task currently being executed, immediately establish a connection with the corresponding meter group, and collect data.

9. The device message mutual access application system based on 5GLAN static multicast according to claim 1 is characterized in that: The static multicast group seals and encrypts the instruction answer and then feedbacks it to the concentrator. If the feedback time exceeds the predefined time threshold, it is determined that the identity of the static multicast group is suspicious, and no data will be transmitted.

10. The device message mutual access application system based on 5GLAN static multicast according to claim 1 is characterized in that: Data transmission between the static multicast group and the concentrator all uses AES encryption. The specific algorithm for the concentrator to perform lossless compression on the encrypted data is the Zlib algorithm.

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