Agricultural blockchain data encryption transmission method for digital economy

Abstract

The application discloses a kind of agricultural blockchain data encryption transmission methods for digital economy, the method constructs and configures agricultural operation type, time window, data type, state verification condition and the highest data precision level of agricultural state transition graph, state transition proof is generated according to the front and rear agricultural state of target plot, operation type, collection time and previous ciphertext state commitment value, and is verified by blockchain verification node, the present application relates to digital information security transmission and agricultural data element circulation technical field.The agricultural blockchain data encryption transmission method for digital economy will agricultural raw data be decomposed into basic data layer and progressive residual layer, and the layer key independent of each other is derived using state transition abstract, plot identification, crop batch identification, data type identification and level identification, so that layer key is bound with specific agricultural state, plot, batch and precision level.

Description

Technical Field

[0001] This invention relates to the fields of secure transmission of digital information and circulation of agricultural data elements, and more specifically, to a method for encrypted transmission of agricultural blockchain data for the digital economy. Background Technology

[0002] With the development of agricultural IoT and data element circulation, data on land environment, crop growth, and agricultural operations need to be securely transmitted between multiple network entities. Existing technologies typically employ methods such as data packet encryption, hash association, blockchain notarization, and access policies to achieve agricultural data sharing, authenticity verification, and access control. For example, CN113377727B discloses a blockchain-based agricultural data sharing scheme that protects raw agricultural data through data packet encryption, hash association, and blockchain notarization. In existing agricultural data transmission, agricultural status verification and data accuracy authorization are usually set separately. When the same plot of land and the same crop batch are at different agricultural stages, the correspondence between the data transmission accuracy and the agricultural status lacks a unified constraint, which can easily lead to a mismatch between data accuracy control and the actual agricultural status, further affecting the orderly transmission of hierarchical data and the consistency of accuracy verification in delivery. Summary of the Invention

[0003] The purpose of this invention is to provide an encrypted transmission method for agricultural blockchain data in the digital economy. This method constrains the highest data accuracy level of agricultural data by verifying the results of agricultural state transitions, and applies this constraint throughout the data layering, layer key derivation, layered encrypted transmission, and delivery verification processes. This ensures that the transmittable accuracy of agricultural data matches the actual agricultural state, thereby improving the reliability of layered encrypted transmission and data delivery accuracy verification.

[0004] This invention achieves the above objective through the following technical solution: a method for encrypted transmission of agricultural blockchain data for the digital economy, the method comprising: Construct an agricultural state transition graph, which includes agricultural state nodes and state transition edges. Each state transition edge is associated with the allowed operation type, time window, data type, state verification condition, and highest data precision level. Obtain the target plot's original agricultural data, plot identifier, crop batch identifier, previous agricultural status, current agricultural status, current operation type, data collection time, and previous encrypted status commitment value, and generate an agricultural status transition proof. The blockchain verification node verifies the agricultural state transition proof according to the state transition edge. When the verification is successful, a state transition summary is generated. When the verification fails, the original agricultural data transmission is blocked. The highest data precision level is determined based on the verified state transition edge, and the original agricultural data is decomposed into a basic data layer and a progressive residual layer not exceeding the highest data precision level. Using the state transition summary, the plot identifier, the crop batch identifier, the data type identifier, and the level identifier as key derivation parameters, a layer key for each data layer is generated, the corresponding data layer is encrypted independently, and the data layer ciphertext, level identifier, and previous layer ciphertext summary are encapsulated into a layered ciphertext transmission unit. Calculate the reconstruction error for different data layer combinations and generate reconstruction error commitments. Write the reconstruction error commitments, hierarchical ciphertext transmission unit indexes, and access policies into the blockchain. The data precision rights certificate of the recipient is verified by a smart contract, and the key share of the corresponding layer key is released when the requested precision level does not exceed the highest data precision level. The receiver reconstructs the layer key, decrypts and overlays the data layer in hierarchical order, verifies the recovered data based on the reconstruction error commitment, and completes delivery or generates an anomaly record based on the verification result.

[0005] Furthermore, the construction of the agricultural state transition graph includes: Multiple agricultural status nodes are set according to the agricultural process of the target crop, and each agricultural status node is configured with a status code and a crop batch field. The state transition edge is established by taking two agricultural state nodes with sequential constraints as the starting node and the target node, respectively. Write the starting state code, target state code, allowed operation type code, time window start point, time window end point, allowed data type code, state verification condition, and highest level sequence number into each state transition edge; The highest level sequence number is used as the upper limit of the number of data layers that can be generated for the corresponding state transition edge, and a graph version identifier is configured for the agricultural state transition graph.

[0006] Furthermore, the generation of the agricultural state transition proof includes: Agricultural event messages are generated in the order of fields: plot identifier, crop batch identifier, previous agricultural status, current agricultural status, current operation type, and data collection time. The raw agricultural data is hashed to obtain a summary of the raw data. The agricultural event message, the original data digest, and the previous encrypted state commitment value are concatenated in a fixed field order to obtain the state proof payload. The state proof payload is hashed to generate the agricultural state transition proof, thus establishing a continuous association between the current agricultural state, the original agricultural data, and the previous encrypted state commitment value.

[0007] Furthermore, the verification of the agricultural state transition proof by the blockchain verification node includes: Based on the state code of the previous agricultural state and the state code of the current agricultural state, query the target state transition edge from the agricultural state transition graph; Verify whether the current operation type is consistent with the allowed operation type code in the target state transition edge, whether the data collection time is between the start and end of the time window, whether the data type of the agricultural raw data is consistent with the allowed data type code, and whether the current agricultural state meets the state verification conditions. Read the previous state record associated with the plot identifier and crop batch identifier from the blockchain, and verify whether the previous encrypted state commitment value is consistent with the previous state record; When all verifications pass, hash calculation is performed on the agricultural state transition proof, verification results and map version identifier to obtain the state transition summary. If any verification fails, a transmission blocking command is output to the data sender, and the failed verification item, plot identifier, crop batch identifier, and data collection time are written to the blockchain.

[0008] Furthermore, the process of decomposing the raw agricultural data into a basic data layer and a progressive residual layer includes: Based on the data type of the agricultural raw data, data precision levels are set in ascending order, with each data precision level corresponding to a defined time sampling interval and spatial grid size. The raw agricultural data is aggregated according to the time sampling interval and spatial grid size of the lowest data precision level to generate the basic data layer. Agricultural data is reconstructed according to the first level of data precision, and the difference between the target data of the first level of data precision and the reconstruction result of the basic data layer is determined as the first progressive residual layer. For subsequent data precision levels, the difference between the target data of the current data precision level and the superimposed reconstruction results of the basic data layer and the preceding progressive residual layer is determined as the current progressive residual layer; Stop generating progressive residual layers with hierarchical indices greater than the highest data precision level.

[0009] Furthermore, the layered ciphertext transmission unit includes: Obtain the root key stored in the key management node, and combine the state transition summary, plot identifier, crop batch identifier, data type identifier, and the current data layer hierarchy identifier into the current key derivation parameters; The root key and the current key derivation parameters are processed by the key derivation function to generate the layer key for the current data layer; An authentication encryption algorithm is used to encrypt the current data layer using the layer key of the current data layer, resulting in the ciphertext of the current data layer and the authentication tag. Write the basic data layer ciphertext, authentication tag, and hierarchy identifier into the hierarchical ciphertext transmission unit corresponding to the basic data layer; Write the ciphertext of the progressive residual layer, the authentication tag, the level identifier, and the ciphertext digest of the previous layer ciphertext transmission unit into the layered ciphertext transmission unit corresponding to the progressive residual layer, so as to form a ciphertext digest chain from the basic data layer to the highest progressive residual layer.

[0010] Furthermore, the generation of the reconstruction error commitment includes: Data reconstruction is performed using the basic data layer and the combination of data layers consisting of the basic data layer and the continuously progressive residual layer, respectively, to obtain reconstructed data corresponding to each data precision level. Calculate the root mean square error between the reconstructed data and the original agricultural data, and normalize the root mean square error by the effective range difference of the corresponding data type to obtain the dimensionless reconstruction error. The dimensionless reconstruction error, data precision level, ciphertext digest of the corresponding hierarchical ciphertext transmission unit, and random commitment parameters are concatenated in a fixed field order to obtain the error commitment payload. The error commitment load is hashed to generate the reconstructed error commitment; Each reconstruction error commitment is associated with its corresponding data precision level, hierarchical encrypted transmission unit index, and state transition summary and written into the blockchain.

[0011] Furthermore, the verification of data accuracy rights certificates via smart contracts includes: Read the recipient's identity identifier, land parcel identifier, crop batch identifier, transaction batch identifier, authorization start time, authorization end time, authorized data purpose, and authorization precision level from the data precision rights certificate; The fields in the data precision rights certificate are matched item by item with the access policies in the blockchain, and the request precision level, the authorization precision level and the highest data precision level are compared. When the fields match, the current time is between the authorization start time and the authorization end time, and the requested precision level is not higher than the authorization precision level and the highest data precision level, determine the target data layer from the basic data layer to the requested precision level. The threshold secret sharing method is used to decompose the layer key of each target data layer into multiple key shares, and the smart contract specifies the key management node that can provide key shares to the verified recipient.

[0012] Furthermore, the receiver decrypts and overlays data layers in hierarchical order, including: Obtain the key share that has reached the threshold from the key management node, and reconstruct the layer key for each target data layer; Read the hierarchical encrypted transmission units in ascending order of hierarchical identifiers and verify the authentication tags in each hierarchical encrypted transmission unit; For the progressive residual layer, the ciphertext digest of the previous layer ciphertext transmission unit is calculated, and the calculation result is compared with the ciphertext digest of the previous layer recorded in the current layer ciphertext transmission unit. When both the authentication tag and the pre-layer ciphertext digest are verified, the data layer ciphertext is decrypted using the corresponding layer key. The plaintext of the basic data layer is used as the initial recovery data. The plaintext of each progressive residual layer is aligned according to the time sampling position and spatial grid position, and then superimposed on the initial recovery data in sequence to obtain the recovery data corresponding to the requested precision level.

[0013] Furthermore, the verification of the recovered data based on the reconstruction error commitment includes: Based on the transaction batch identifier and the request precision level, the corresponding reconstruction error commitment, the ciphertext digest of the layered ciphertext transmission unit, and the error limit are read from the blockchain; Calculate the actual root mean square error between the recovered data and the transaction verification data, and normalize it using the effective range difference of the data type to which the transaction verification data belongs, to obtain the actual reconstruction error; Obtain the random commitment parameter corresponding to the reconstruction error commitment, and concatenate the actual reconstruction error, the requested precision level, the ciphertext digest of the hierarchical ciphertext transmission unit, and the random commitment parameter according to the fixed field order and perform hash calculation to obtain the commitment to be verified. When the commitment to be verified is consistent with the on-chain reconstruction error commitment and the actual reconstruction error is not higher than the error limit, the smart contract generates data delivery confirmation information and executes transaction settlement. If the commitment to be verified is inconsistent with the on-chain reconstruction error commitment, or if the actual reconstruction error exceeds the error limit, transaction settlement will be suspended, and the transaction batch identifier, request precision level, actual reconstruction error, and state transition summary will be written into the data delivery anomaly record.

[0014] The beneficial effects of this invention are as follows: 1. This invention takes the legality of agricultural state transitions as a prerequisite for the generation and transmission of high-precision agricultural data. By jointly verifying the allowed operation types, time windows, allowed data types, and state verification conditions, it can prevent out-of-order agricultural operations, abnormally collected data, or data that is not continuous with the previous state record from entering the high-precision transmission link.

[0015] 2. This invention allows the verified agricultural status to directly determine the highest data precision level that can be generated, and locks data layers that exceed this precision level, thus restricting the premature generation or unauthorized transmission of high-precision agricultural data from the data generation and key derivation stages.

[0016] 3. This invention decomposes agricultural raw data into a basic data layer and a progressive residual layer, and uses state transition summaries, plot identifiers, crop batch identifiers, data type identifiers and hierarchical identifiers to derive mutually independent layer keys, so that the layer keys are bound to specific agricultural states, plots, batches and precision levels.

[0017] 4. The present invention writes the previous layer's ciphertext digest into the layered ciphertext transmission unit of the progressive residual layer, forming a ciphertext digest chain from the low-precision layer to the high-precision layer. This can identify data layer deletion, replacement, and order swapping, and prevent the receiving end from bypassing the preceding data layer to directly recover high-precision agricultural data.

[0018] 5. This invention utilizes data precision rights certificates to control the key share release range and verifies the actual precision of the recovered data through on-chain reconstruction error commitment verification, thereby forming a closed loop for agricultural data status verification, layered encryption, orderly transmission, precision-based authorization, delivery verification, and transaction settlement. Attached Figure Description

[0019] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings: Figure 1 A flowchart illustrating an agricultural blockchain data encryption transmission method for the digital economy provided by this invention; Figure 2 This invention provides a diagram of agricultural state transitions and a schematic diagram of the highest data precision level control. Figure 3 A schematic diagram of the structure of the agricultural blockchain data encryption transmission network provided by the present invention; Figure 4 This is a schematic diagram illustrating the agricultural data layering, layer key derivation, layered encrypted transmission, and delivery accuracy verification provided by the present invention. Detailed Implementation

[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments. The following embodiments are used to explain the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Equivalent substitutions made by those skilled in the art for agricultural status types, data precision levels, cryptographic algorithms, number of network nodes, or data types without departing from the concept of the present invention should all be included within the scope of protection of the present invention.

[0021] like Figures 1-3As shown, in one optional embodiment, the present invention can operate on an agricultural data transmission network consisting of a data sender, a blockchain verification node, a key management node, a ciphertext storage node, a smart contract, and a data receiver. The data sender is used to acquire raw agricultural data, generate agricultural state transition proofs, perform data layering, and generate layered ciphertext transmission units; the blockchain verification node is used to store agricultural state transition graphs, verify agricultural state transition proofs and record state transition summaries, reconstruct error commitments, and access policies; the key management node is used to store root keys or layer key shares; the ciphertext storage node is used to store layered ciphertext transmission units; the smart contract is used to verify data accuracy rights certificates and control key share release and transaction settlement; the data receiver is used to reconstruct layer keys, decrypt layer by layer, recover agricultural data, and verify delivery accuracy.

[0022] Raw agricultural data includes at least one of the following: soil moisture content data, soil temperature data, air temperature data, air humidity data, irrigation flow data, fertilization operation data, crop growth data, pest and disease monitoring data, agricultural machinery operation data, and agricultural remote sensing data. Data of different physical quantities are stratified, densified, and error calculated separately; data of different dimensions are not directly weighted or superimposed.

[0023] Example 1: This embodiment includes the following steps: S1. Construct a transition diagram of agricultural status.

[0024] Multiple agricultural state nodes are set up according to the production cycle of the target crop and the sequence of agricultural operations, and state transition edges are established between agricultural state nodes with legal sequential constraints. For example... Figure 2 As shown, this embodiment sets up the following states for the corn planting process: waiting to be sown, sown, emergence, growth, irrigation, fertilization, maturity, and harvest. Each agricultural status node is configured with a unique status code, crop batch field, and status formation conditions.

[0025] Each state transition edge must be configured with at least the following: starting state code, target state code, allowed operation type code, time window start point, time window end point, allowed data type code, state verification condition, highest data precision level, and graph version identifier. The allowed operation type code limits the agricultural operations that trigger the corresponding state transition; the time window limits the allowed time range for agricultural operations; the allowed data type code limits the data types that can be generated and transmitted in the corresponding state; the state verification condition determines whether the target agricultural state has actually been formed; and the highest data precision level limits the highest precision of agricultural data that can be generated and transmitted in the current state.

[0026] This embodiment sets up a basic data layer. First progressive precision layer Second progressive precision layer and the third progressive precision layer Basic data layer The time sampling interval is The spatial scope is the entire target plot, used to characterize the daily average value, overall trend, and data range of agricultural data; the first progressive precision layer The time sampling interval is The side length of the spatial grid is This is used to characterize hourly changes and differences in land parcel zoning; the second progressive precision layer The time sampling interval is The side length of the spatial grid is It is used to characterize short-term changes and local spatial anomalies; the third progressive precision layer The time sampling interval is The side length of the spatial grid is It is used to recover the sampling details of the original output of the proximity sensor.

[0027] The time sampling interval for each data precision level is determined based on the minimum effective agricultural change cycle that the corresponding agricultural data can reflect. The side length of the spatial grid is determined based on the actual sensor installation spacing and the spatial resolution required for data transactions. A unified time reference and a unified spatial coordinate reference are used for the same data batch. The highest data precision level corresponding to the sown state is set to... Seedling emergence status corresponds to Growth status and irrigation status correspond Maturity and harvesting status correspond to The aforementioned correspondences are written into the blockchain before the agricultural state transition graph is published and managed through graph version identifiers.

[0028] The time window for state transition edges is determined based on the actual operation times of the 20 most recent effective planting batches of the same crop. The lead-in or delay-out amount of the actual operation time relative to the planned operation time for each historical batch is calculated, and the absolute time deviation is... The quantile value is rounded up to the nearest integer. This serves as the allowable deviation before and after the planned operation time. The allowable deviation shall not be less than [amount missing]. And must not exceed If there are fewer than 20 valid batches in the past, the start and end times of the operation shall be adopted as specified in the agricultural production plan.

[0029] Taking the transition from the growth state to the irrigation state as an example, the state verification conditions for the corresponding state transition edge include: the irrigation valve is in the open state; the irrigation flow is continuous. Not less than The plot identification in the irrigation operation record matches the target plot identification; after irrigation begins Within the target area, the average soil moisture content should increase by at least 0.5 percentage points compared to before irrigation begins.

[0030] Irrigation flow threshold According to the rated flow rate of the irrigation pump of This setting is used to exclude situations where the valve is open but no effective irrigation flow is generated; the continuous time is set to... This is used to eliminate instantaneous fluctuations caused by the start-up of irrigation pumps and valve switching. The soil moisture content change threshold of 0.5 percentage points is determined based on the sensor measurement error. In this embodiment, the soil moisture content sensor has a measurement error of ±0.2 percentage points, and the change threshold is greater than twice the absolute value of the measurement error to avoid misinterpreting sensor measurement fluctuations as effective irrigation responses.

[0031] S2. Obtain raw agricultural data and generate proof of agricultural state transitions.

[0032] The data sending end acquires the raw agricultural data corresponding to the target plot and simultaneously obtains the plot identifier, crop batch identifier, previous agricultural activity status, current agricultural activity status, current operation type, data collection time, and previous encrypted status commitment value. The plot identifier is used to uniquely indicate the plot to which the agricultural data belongs; the crop batch identifier is used to distinguish data generated from the same plot in different planting cycles; and the previous encrypted status commitment value is used to establish a continuous association between the current agricultural data and the agricultural data corresponding to the previous agricultural activity status.

[0033] Plot identifiers and crop batch identifiers are each encoded using 16 bytes; agricultural status codes and operation type codes are each encoded using 2-byte unsigned integers; data acquisition time is represented by an 8-byte timestamp; and the previous encrypted status commitment value is represented by a 32-byte hash value. Before generating agricultural status transition proofs, the raw agricultural data undergoes field integrity checks, time synchronization checks, sensor range checks, and data type checks.

[0034] Soil moisture content is expressed as volumetric moisture content, in units of... The valid value range is to The unit of irrigation flow rate is The valid value range is to Data exceeding the corresponding valid value range is marked as abnormal data and will not be included in the generation of agricultural status transition proof for the current data batch.

[0035] The data sending end performs hash calculation on the raw agricultural data to obtain a raw data summary, and concatenates the corresponding parameters according to the preset field order. The agricultural state transition proof is generated according to formula (1):

[0036] In the formula, Indicates the first Proof of the transition from the agricultural state; Indicates the output length is Cryptographic hash functions; Indicates land parcel identification; Indicates crop batch identification; Indicates the previous agricultural condition; Indicates the current state of agricultural activities; Indicates the current operation type; Indicates the data collection time; This represents the commitment value of the previous ciphertext state; This represents the current raw agricultural data; the symbol "∥" indicates that the data is concatenated according to a fixed field order.

[0037] The previous encrypted state commitment value is generated jointly by the state transition digest corresponding to the previous agricultural state and the encrypted digest of the highest-level hierarchical encrypted transmission unit of the previous data batch. If any historical agricultural state, historical data batch, or historical encrypted record changes, the current agricultural state transition proof will fail verification. The data sender sends the agricultural state transition proof, the original data digest, and the corresponding verification parameters to the blockchain verification node.

[0038] S3. Verify the proof of agricultural state transition.

[0039] The blockchain verification node queries the corresponding target state transition edge from the agricultural state transition graph based on the previous agricultural state code and the current agricultural state code. It determines whether the current operation type is consistent with the allowed operation type code, whether the data collection time is within the time window, whether the data type of the agricultural raw data is consistent with the allowed data type code, and whether the equipment operating status, irrigation flow, soil moisture content changes, and agricultural operation records meet the state verification conditions.

[0040] The blockchain verification node reads the previous state record associated with the plot identifier and crop batch identifier from the blockchain, determines whether the previous encrypted state commitment value is consistent with the previous state record, and recalculates the agricultural state transition proof according to formula (1), and determines whether the recalculation result is consistent with the proof submitted by the data sender.

[0041] Once all verification items pass, the blockchain verification node concatenates the agricultural state transition proof, verification results, graph version identifier, and current block height in a fixed order and performs hash calculation to obtain a state transition digest. This state transition digest serves as a common parameter for subsequent determination of the highest data precision level, layer key derivation, ciphertext index association, and delivery precision verification.

[0042] When any verification item fails, the blockchain verification node outputs a transmission blocking command to the data sender. The data sender stops generating progressive residual layers, does not perform layer key derivation or data layer encryption, and generates an anomaly status record. The anomaly status record includes the plot identifier, crop batch identifier, previous agricultural activity status, current agricultural activity status, failed verification item, actual detection value, corresponding verification conditions, data collection time, and a summary of the original agricultural data.

[0043] S4. Determine the highest data precision level and stratify the raw agricultural data.

[0044] After the agricultural state transition verification is successful, the data sending end determines the highest data precision level that the current raw agricultural data can be generated based on the highest level sequence number recorded in the target state transition edge. Data layers with a level sequence number not greater than the highest level sequence number are set to a generateable state, while data layers with a level sequence number greater than the highest level sequence number are set to a locked state. Data layers in the locked state do not participate in data generation, layer key derivation, key share release, or data transmission.

[0045] Before data stratification, agricultural raw data of the same data type are mapped to a unified time coordinate and spatial grid. For data with inconsistent time intervals, the timestamps are used to align to the sampling positions of the corresponding precision level; for data with inconsistent spatial locations, the sampling point coordinates are mapped to the corresponding spatial grid. The units for the soil moisture content base data layer and each progressive residual layer are all [units missing]. The units for the irrigation flow base data layer and each progressive residual layer are all... Addition is not performed between different data types.

[0046] according to Based on the corresponding time sampling intervals and spatial ranges, the raw agricultural data is aggregated temporally and spatially to generate a basic data layer. ;according to The corresponding time sampling interval and spatial grid size generate the first-precision target data. The difference between the first-precision target data and the reconstruction result of the basic data layer is determined as the first progressive residual layer. ;according to The corresponding time sampling interval and spatial grid size generate the second-precision target data. The difference between the second-precision target data and the superposition result of the base data layer and the first progressive residual layer is determined as the second progressive residual layer. When the current agricultural state allows for generation At the same time, the third progressive residual layer is generated in the same manner. .

[0047] No. The reconstructed data corresponding to the data precision level is determined according to equation (2):

[0048] In the formula, Indicates the first Reconstructed data corresponding to data precision levels; Represents the basic data layer; Indicates the first Progressive residual layer; This indicates the number of progressive residual layers participating in the current data reconstruction. The base data layer and the progressive residual layers have the same data type, the same physical units, and the same aligned data dimensions. (Parameters...) The number of progressive residual layers allowed to be generated under the current agricultural conditions must not exceed the limit.

[0049] When the highest data precision level is At this time, the data sending end only generates the basic data layer, the first progressive residual layer, and the second progressive residual layer, and does not generate the third progressive residual layer.

[0050] S5. Derive the layer key and generate the layered ciphertext transmission unit.

[0051] This embodiment uses a length of The root key is stored in the hardware security module of the key management node, and the data sender only has controlled key derivation access. For any data layer to be encrypted, the data sender combines the state transition digest, plot identifier, crop batch identifier, data type identifier, and the current data layer's level identifier into key derivation parameters, and the layer key is generated according to equation (3):

[0052] In the formula, Indicates the first The layer key corresponding to the data layer has a key length of . ; Represents the key derivation function; This indicates the root key corresponding to the data provider; This represents a summary of the current state transition; Indicates land parcel identification; Indicates crop batch identification; Indicates data type identifier; This indicates the hierarchy identifier of the current data layer.

[0053] Each key derivation parameter uses a fixed-length encoding to avoid ambiguity caused by splicing adjacent fields. Since state transition digests participate in key derivation, different layer keys are generated for the same plot and the same crop batch under different agricultural conditions; since hierarchical identifiers participate in key derivation, the basic data layer and each progressive residual layer under the same agricultural condition use independent layer keys.

[0054] The data sender uses an authentication encryption algorithm to independently encrypt each data layer. The authentication encryption key length is [length missing]. The length of the random number is The length of the certification label is Each data layer uses a unique random number; the random number is generated by a cryptographically secure random number generator and duplicate checks are performed within the validity period of the same layer key. If duplicate random numbers are detected, a new random number is generated before encryption is performed.

[0055] like Figure 4 As shown, the hierarchical encrypted transmission unit corresponding to the basic data layer includes the protocol version, plot identifier, crop batch identifier, data type identifier, hierarchical identifier, state transition digest, random number, basic data layer ciphertext, and authentication tag; the hierarchical encrypted transmission unit corresponding to the progressive residual layer also includes the ciphertext digest of the previous layer's hierarchical encrypted transmission unit. The length of the previous layer's ciphertext digest is... The basic data layer, the first progressive residual layer, and subsequent progressive residual layers form a ciphertext digest chain in ascending order of hierarchy. When any preceding unit is deleted, replaced, or its order is reversed, the ciphertext digest of the preceding layer recorded in subsequent units will be inconsistent with the recalculated result, thus preventing the receiver from continuing to recover high-precision agricultural data.

[0056] S6. Calculate the reconstruction error and generate a reconstruction error commitment.

[0057] The data sending end reconstructs agricultural data using the basic data layer, the basic data layer and the first progressive residual layer, and the basic data layer and the first two progressive residual layers, respectively. When the third progressive residual layer is allowed to be generated, the basic data layer and all progressive residual layers are used for the highest precision reconstruction. To avoid the influence of different physical quantities on error judgment, each data type is normalized using its effective range. The dimensionless reconstruction error is calculated according to formula (4):

[0058] In the formula, Indicates the first The dimensionless reconstruction error corresponding to the data precision level; Indicates the number of valid samples used in error calculation; Indicates the first One agricultural raw data; Indicates the first The data precision level corresponds to the first One reconstructed data; Indicates the upper limit of the effective range of the corresponding data type; This indicates the lower limit of the valid range for the corresponding data type.

[0059] Regarding soil moisture content data Pick , Pick For irrigation flow data, Pick , Pick The data difference in equation (4) and the effective range difference have the same physical units, and the result of dividing them has no physical dimensions. Therefore, This is a dimensionless numerical value. When the upper limit and lower limit of the effective range of the corresponding data type are the same, the data batch is marked as range configuration abnormal data, and no reconstruction error commitment is generated.

[0060] This embodiment is set The corresponding upper limit of the initial dimensionless reconstruction error is 0.080. The corresponding upper limit of the initial dimensionless reconstruction error is 0.040. The corresponding upper limit of the initial dimensionless reconstruction error is 0.015. The corresponding upper limit of the initial dimensionless reconstruction error is 0.005. The initial error upper limit is determined based on the time sampling interval, spatial grid size, and sensor measurement error of the corresponding accuracy level. The higher the data accuracy level, the smaller the allowable reconstruction error.

[0061] Once at least 30 qualified transaction batches of the same data type and precision level have been accumulated, the upper limit of error is updated based on the historical reconstruction errors of the most recent 30 qualified transaction batches. The most recent 30 dimensionless reconstruction errors are sorted in ascending order, and the 29th value is taken and rounded up to 0.001, which is used as the updated upper limit of error. The updated upper limit of error must not be lower than 1.5 times the normalized measurement error of the sensor. Taking a soil moisture sensor as an example, its measurement error is ±0.2 percentage points, corresponding to a normalized measurement error of 0.002; therefore, the corresponding upper limit of error must not be lower than 0.003.

[0062] The data sending end converts the dimensionless reconstruction error into a precision of... The fixed-point number, and the ciphertext digest of the corresponding hierarchical ciphertext transmission unit, and the data precision level. Random commitment parameters are concatenated according to a fixed field order to generate an error commitment payload; the error commitment payload is then subjected to an output with a length of... The hash calculation yields the reconstruction error commitment. Using fixed-point encoding avoids inconsistencies in commitment verification caused by different rounding methods among different computing nodes. The data sender writes the state transition summary, data precision level, reconstruction error commitment, hierarchical encrypted transmission unit index, error upper limit, access policy, graph version identifier, and data version identifier into the blockchain.

[0063] S7. Verify the data accuracy rights certificate and release the key share.

[0064] The data receiving end submits a data accuracy rights certificate and a data acquisition request to the smart contract. The data accuracy rights certificate includes the receiver's identity identifier, target plot identifier, crop batch identifier, transaction batch identifier, authorization start time, authorization end time, authorized data purpose, and authorized accuracy level.

[0065] The smart contract verifies the issuing entity and digital signature of the credential, the recipient's identity, the target plot and crop batch, the authorization period, the purpose of the authorized data, the relationship between the requested precision level and the authorized precision level, and the relationship between the requested precision level and the highest data precision level allowed by the current agricultural status. When all verification items pass, the smart contract determines the target data layer from the basic data layer to the requested precision level and triggers the key share release process for the corresponding layer key.

[0066] This embodiment sets up 5 key management nodes and adopts a 3 / 5 threshold secret sharing rule. Each layer of key is decomposed into 5 key shares. The data receiving end can reconstruct the corresponding layer key after obtaining any 3 valid key shares. The threshold value of 3 is determined based on the fault tolerance requirement that the system allows 2 key management nodes to be offline, and fewer than 3 key management nodes cannot independently recover the complete layer key. Before releasing a key share, the key management node verifies the authorization event identifier, transaction batch identifier, target data layer identifier, and receiver identity identifier generated by the smart contract. If any verification item fails, the smart contract refuses to release the key share and writes the requesting subject, request time, request precision level, and rejection reason to the blockchain.

[0067] S8. Decrypt agricultural data in hierarchical order and verify delivery accuracy.

[0068] The data receiver obtains the key share that has reached the threshold from the key management node, reconstructs the layer key corresponding to each target data layer, and reads the layered ciphertext transmission units in ascending order of layer identifier. For each layered ciphertext transmission unit, the data receiver verifies the authentication tag using the corresponding layer key; for progressive residual layers, it also calculates the ciphertext digest of the previous layered ciphertext transmission unit and compares the calculation result with the previous layer ciphertext digest recorded in the current layered ciphertext transmission unit.

[0069] When authentication tag verification fails, the corresponding data layer is marked as ciphertext integrity abnormal and decryption stops. When preceding layer ciphertext digest verification fails, the corresponding data layer is marked as transmission order abnormal, and bypassing the preceding data layer to directly recover high-precision agricultural data is not allowed. After both authentication tag and preceding layer ciphertext digest verification are successful, the data receiver uses the corresponding layer key to decrypt the data layer ciphertext, obtaining the basic data layer plaintext and the progressive residual layer plaintext.

[0070] The data receiver uses the plaintext of the basic data layer as the initial recovery data, aligns the plaintext of each progressive residual layer according to the time sampling position and spatial grid position, and superimposes them sequentially in order of increasing level identifier to obtain the recovery data corresponding to the requested precision level. The transaction verification node reads the corresponding reconstruction error commitment, layered encrypted transmission unit digest, and error upper limit according to the transaction batch identifier and the requested precision level, calculates the actual reconstruction error of the recovery data according to equation (4), and converts the actual reconstruction error into a precision of... fixed point number.

[0071] The actual reconstruction error fixed point number, requested precision level, layered encrypted transmission unit digest, and corresponding random commitment parameters are concatenated according to the field order used when generating the reconstruction error commitment to obtain the commitment payload to be verified, and then hashed. When the commitment to be verified is consistent with the on-chain reconstruction error commitment and the actual reconstruction error is not higher than the error limit, the smart contract generates data delivery confirmation information and executes transaction settlement; when the commitment to be verified is inconsistent or the actual reconstruction error is higher than the error limit, the smart contract suspends transaction settlement and generates a data delivery anomaly record containing the transaction batch identifier, land parcel identifier, crop batch identifier, requested precision level, actual reconstruction error, error limit, state transition digest, layered encrypted transmission unit digest, anomaly type, and anomaly occurrence time.

[0072] Example 2: This embodiment uses area as... Taking a corn-growing plot as an example, the plot identifier for the target plot is set to... Crop batch identifier set to 800 soil moisture sampling points were set up at the target site, with an average spacing of [missing information]. .

[0073] The original sampling interval of the soil moisture sensor is The measurement range is to The measurement error is ±0.2 percentage points; the original sampling interval of the irrigation flow sensor is... The measurement range is to The measurement error is ± The rated flow rate of the irrigation pump is .

[0074] The current agricultural status has transitioned from the growing state to the irrigated state. The permitted operation type for this state transition is irrigation initiation, with a permitted time window from 06:00 to 12:00 on June 18, 2026. Permitted data types are soil moisture content data and irrigation flow rate data, with a maximum data precision level of [missing information]. .

[0075] The actual irrigation start time was 08:10 on June 18, 2026. The average irrigation flow rate between 08:10 and 08:15 was... higher than The effective traffic threshold, and the continuous duration reaches The average soil moisture content of the target plot before irrigation began was [missing information]. After irrigation begins The average soil moisture content of the target plot is This represents an increase of 0.8 percentage points, exceeding the 0.5 percentage point threshold for state verification.

[0076] Blockchain verification nodes verify the current operation type, data collection time, irrigation flow rate, soil moisture content change, allowed data types, and the previous encrypted state commitment value. Once all verifications pass, a state transition digest is generated. The data sender obtains continuous... The soil moisture content data consisted of 360 time sampling locations and 800 spatial sampling points, totaling 288,000 valid samples.

[0077] The data sending end generates a basic data layer according to the spatial scope of the land parcel; according to Time sampling interval and The spatial grid generates the first progressive residual layer; according to Time sampling interval and The spatial grid generates a second progressive residual layer. Since the highest data precision level corresponding to the current irrigation status is... The data sending end does not generate Time sampling interval and The third progressive residual layer corresponding to the spatial grid.

[0078] The dimensionless reconstruction error corresponding to each data precision level is calculated using equation (4), and the basic data layer... The dimensionless reconstruction error is 0.036, which is less than the upper limit of error 0.080; the combination of the basic data layer and the first progressive residual layer corresponds to The dimensionless reconstruction error is 0.014, which is less than the upper limit of 0.040; the combination of the basic data layer, the first progressive residual layer, and the second progressive residual layer corresponds to... The dimensionless reconstruction error is 0.004, which is less than the upper limit of 0.015. The data sending end generates... , and The corresponding reconstruction error commitment is then written into the blockchain, along with the reconstruction error commitment, the hierarchical ciphertext transmission unit index, the state transition summary, and the access policy.

[0079] The precision level of the data accuracy certificate authorization submitted by the data receiving end is: Due to the requested precision level Not higher than the credential authorization precision level And not higher than the highest data precision level allowed in the current state. The smart contract identifies the basic data layer and the first progressive residual layer as the target data layer, and does not release the key share corresponding to the second progressive residual layer.

[0080] The data receiver obtains valid key shares from three of the five key management nodes, reconstructs the layer keys corresponding to the basic data layer and the first progressive residual layer, and sequentially verifies the authentication tag and the ciphertext digest of the preceding layer to complete the data layer decryption and layer-by-layer stacking. The recovered data... The dimensionless reconstruction error of agricultural data is 0.014, and the commitment to be verified is consistent with the on-chain data. The reconstruction error commitment is consistent, and the actual reconstruction error is lower than the upper limit of 0.040. Based on this, the smart contract completes the delivery of agricultural data and transaction settlement.

[0081] Example 3: This embodiment uses soil conductivity data and fertilizer solution flow data generated during rice topdressing operations as examples to illustrate the implementation process of the present invention under different crop conditions, agricultural conditions, and data accuracy requirements. This embodiment follows the agricultural condition transition proof, data layering, layer key derivation, and dimensionless reconstruction error calculation methods from Embodiment 1.

[0082] The target plot is of area Rice planting plots, the plots are marked as follows: Crop batch identifier set to The target plot's plan dimensions are: × ,according to × The spatial grid layout of the data collection locations resulted in a total of 1600 spatial sampling points.

[0083] The initial sampling interval of the soil conductivity sensor is The measurement range is to The measurement error is ± The original sampling interval of the fertilizer solution flow sensor is... The measurement range is to The measurement error is ± The measuring range of the fertilizer weighing device is: to The measurement error is ± All sensors use the same network time source for time synchronization, and the time synchronization error does not exceed [a certain value]. .

[0084] In this embodiment, the previous agricultural state is the tillering state, the current agricultural state is the topdressing state, and the current operation type is variable topdressing initiation. In the agricultural state transition diagram, the state transition edges corresponding to the tillering state to the topdressing state are configured as follows: allowed operation type is variable topdressing initiation; allowed data types are soil conductivity data, fertilizer solution flow data, and fertilizer weighing data; allowed time window is from 05:30 to 10:30 on July 12, 2026; the highest data precision level is... The version identifier is: .

[0085] The allowable time window is determined based on the actual operation time of the most recent 20 topdressing batches in similar rice fields. The deviations between the actual start time and the planned start time of these 20 historical batches are statistically analyzed, and the absolute deviation is... quantile value Round up to the nearest integer. Therefore, the allowable start time range is determined with the planned start time of 07:30 as the center; considering the coverage area of ​​this topdressing prescription, the allowable delay after the planned end time is set to... The final time window ends at 10:30.

[0086] The following state verification conditions are set for the corresponding state transition edges: the variable fertilization controller is in the execution state, and the plot identifier read by the controller is consistent with the target plot identifier; the fertilizer solution flow rate is continuous. Not less than The actual fertilizer application quality is located at to Between; after topdressing begins The conductivity of the fertilizer solution at the outlet should increase by at least [percentage missing] compared to before the start of topdressing. The timestamp difference between fertilizer solution flow data, fertilizer weighing data, and soil electrical conductivity data should not exceed [a certain value]. .

[0087] Fertilizer flow rate threshold According to the rated flow rate of the fertilizer pump of This setting is used to rule out situations such as fertilizer pump running dry, partial pipeline blockage, and valves not being fully open; the continuous time is set to... This is used to eliminate short-term fluctuations caused during the fertilizer pump start-up and pipeline filling phases. The fertilizer application rate specified in this topdressing prescription is [amount missing]. Considering the allowable deviation of agronomic prescriptions is ± The allowable total deviation is set to ± due to measurement errors of the weighing device and pipeline residues. Therefore, the actual fertilizer application quality range is determined as follows: to .

[0088] Fertilizer solution outlet conductivity change threshold Determined based on the measurement error of the conductivity sensor. The sensor measurement error is ± The change threshold is 6 times the absolute value of the measurement error, which is used to distinguish the change in conductivity caused by the injection of effective fertilizer solution from random fluctuations in the sensor.

[0089] The topdressing operation was initiated at 07:18 on July 12, 2026. From 07:18 to 07:28, the average flow rate of the fertilizer solution was... Minimum flow rate is All higher than The effective flow threshold; after the topdressing operation is completed, the net fertilizer application mass recorded by the fertilizer weighing device is [value missing]. It is within the permissible range. The average conductivity of the fertilizer solution outlet before topdressing began was [value missing]. After topdressing begins The average value is ,Increase higher than The status verification threshold; the maximum timestamp difference among the three types of data is less than The synchronization threshold.

[0090] The data sending end generates the agricultural state transition proof according to formula (1). The blockchain verification node query graph version identifier is... The agricultural state transition diagram is used to sequentially verify the current operation type, allowed time window, allowed data type, fertilizer solution flow rate, fertilizer application quality, conductivity change, data time synchronization status, and the commitment value of the previous encrypted state. After all verification items pass, a current state transition summary is generated, and the highest data precision level allowed for the current topdressing state is determined. ; level It is set to a locked state.

[0091] In this embodiment, the basic data layer use Time statistical range and the spatial range of the entire target plot; first progressive precision layer use Time sampling interval and × Spatial grid; second progressive precision layer use Time sampling interval and × Spatial grid; third progressive precision layer use Time sampling interval and × Spatial grid. Because the highest data precision level allowed in the current state is... The data sending end only generates the basic data layer, the first progressive residual layer, and the second progressive residual layer.

[0092] This topdressing operation continued The raw soil electrical conductivity data includes 48 temporal sampling locations and 1600 spatial sampling points, totaling 76,800 valid samples; the raw fertilizer solution flow rate data includes 240 valid samples. Different data types were stratified and error calculated separately. and The data is overlaid.

[0093] For soil electrical conductivity data, the data transmitter first generates a basic data layer based on the average value of the entire plot, and then... Time sampling interval and × The spatial grid generates first-precision target data, and the difference between the first-precision target data and the reconstruction result of the base data layer is determined as the first progressive residual layer; subsequently, according to... Time sampling interval and × The spatial grid generates second-precision target data, and the difference between the second-precision target data and the result of superimposing the base data layer and the first progressive residual layer is determined as the second progressive residual layer. For fertilizer solution flow data, the base data layer records... Average flow rate during operation, supplemented by the first progressive residual layer Flow changes within a time interval, supplemented by the second progressive residual layer Traffic flow changes within a time interval.

[0094] The data sending end transmits the current state transition summary and the land parcel identifier according to formula (3). Crop batch identification Data type identifiers and level identifiers are used as key derivation parameters to generate independent keys for the basic data layer, the first progressive residual layer, and the second progressive residual layer. Layer keys. Each data layer is independently encrypted using an authentication encryption algorithm, with a random number length of [length missing]. The length of the certification label is and form a group point to The pre-sequence layer ciphertext digest chain.

[0095] The reconstruction error is calculated according to equation (4). The effective range of soil electrical conductivity data is... to , , and The corresponding dimensionless reconstruction errors are 0.047, 0.019, and 0.007, respectively, all below the corresponding upper limit of error; the effective range of the fertilizer solution flow rate data is... to , , and The corresponding dimensionless reconstruction errors are 0.041, 0.016, and 0.006, respectively, all below the corresponding upper limit of error. The data sending end generates... , and The corresponding reconstruction error commitment is made, and the relevant index, state transition summary, error limit, access policy and data version identifier are written into the blockchain.

[0096] The data precision rights certificate authorization precision level of the first data recipient is: The authorized use is for analyzing the effects of topdressing on rice. After the smart contract verification is successful, , and The corresponding data layer is determined as the target data layer. The first data receiver obtains valid key shares from 3 out of 5 key management nodes, reconstructs the corresponding layer keys, verifies the authentication tags and previous layer ciphertext digests in ascending order of hierarchy, and completes the decryption and overlay of each data layer. The recovered soil electrical conductivity... The dimensionless reconstruction error of the data is 0.007, and the fertilizer solution flow rate is... The dimensionless data reconstruction error is 0.006, and the corresponding commitments to be verified are consistent with the on-chain commitments. The smart contract completes the data delivery confirmation and transaction settlement.

[0097] The authorized precision level recorded in the data precision rights certificate of the second data recipient is: and request to obtain Time sampling interval and × The data corresponding to the spatial grid. Although the credential authorization precision level is... However, the highest data precision level allowed under the current topdressing conditions is... The smart contract therefore refused to release. The corresponding key share is recorded in the blockchain, along with the recipient's identity, request time, requested precision level, current highest data precision level, and reason for rejection. Therefore, the actual data precision that the data recipient can obtain is constrained by both the equity certificate and the current agricultural state transition result.

[0098] The above embodiments provide a detailed description of the present invention. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A method for encrypted transmission of agricultural blockchain data for the digital economy, characterized in that, The method includes: Construct an agricultural state transition graph, which includes agricultural state nodes and state transition edges. The state transition edges are associated with allowed operation types, time windows, data types, state verification conditions, and the highest data precision level. Obtain the target plot's original agricultural data, plot identifier, crop batch identifier, previous agricultural status, current agricultural status, current operation type, data collection time, and previous encrypted status commitment value, and generate an agricultural status transition proof. The blockchain verification node verifies the agricultural state transition proof according to the state transition edge. When the verification is successful, a state transition summary is generated. When the verification fails, the original agricultural data transmission is blocked. The highest data precision level is determined based on the verified state transition edge, and the original agricultural data is decomposed into a basic data layer and a progressive residual layer not exceeding the highest data precision level. Using the state transition summary, the plot identifier, the crop batch identifier, the data type identifier, and the level identifier as key derivation parameters, a layer key for each data layer is generated, the corresponding data layer is encrypted independently, and the data layer ciphertext, level identifier, and previous layer ciphertext summary are encapsulated into a layered ciphertext transmission unit. Calculate the reconstruction error for different data layer combinations and generate reconstruction error commitments. Write the reconstruction error commitments, hierarchical ciphertext transmission unit indexes, and access policies into the blockchain. The data precision rights certificate of the recipient is verified by a smart contract, and the key share of the corresponding layer key is released when the requested precision level does not exceed the highest data precision level. The receiver reconstructs the layer key, decrypts and overlays the data layer in hierarchical order, verifies the recovered data based on the reconstruction error commitment, and completes delivery or generates an anomaly record based on the verification result.

2. The method for encrypted transmission of agricultural blockchain data for the digital economy according to claim 1, characterized in that, The construction of the agricultural state transition diagram includes: Multiple agricultural status nodes are set according to the agricultural process of the target crop, and each agricultural status node is configured with a status code and a crop batch field. The state transition edge is established by taking two agricultural state nodes with sequential constraints as the starting node and the target node, respectively. Write the starting state code, target state code, allowed operation type code, time window start point, time window end point, allowed data type code, state verification condition, and highest level sequence number into each state transition edge; The highest level sequence number is used as the upper limit of the number of data layers that can be generated for the corresponding state transition edge, and a graph version identifier is configured for the agricultural state transition graph.

3. The method for encrypted transmission of agricultural blockchain data for the digital economy according to claim 1, characterized in that, The generation of agricultural state transition proofs includes: Agricultural event messages are generated in the order of fields: plot identifier, crop batch identifier, previous agricultural status, current agricultural status, current operation type, and data collection time. The raw agricultural data is hashed to obtain a summary of the raw data. The agricultural event message, the original data digest, and the previous encrypted state commitment value are concatenated in a fixed field order to obtain the state proof payload. The state proof payload is hashed to generate the agricultural state transition proof, thus establishing a continuous association between the current agricultural state, the original agricultural data, and the previous encrypted state commitment value.

4. The method for encrypted transmission of agricultural blockchain data for the digital economy according to claim 2, characterized in that, The verification of agricultural state transition proofs by blockchain verification nodes includes: Based on the state code of the previous agricultural state and the state code of the current agricultural state, query the target state transition edge from the agricultural state transition graph; Verify whether the current operation type is consistent with the allowed operation type code in the target state transition edge, whether the data collection time is between the start and end of the time window, whether the data type of the agricultural raw data is consistent with the allowed data type code, and whether the current agricultural state meets the state verification conditions. Read the previous state record associated with the plot identifier and crop batch identifier from the blockchain, and verify whether the previous encrypted state commitment value is consistent with the previous state record; When all verifications pass, hash calculation is performed on the agricultural state transition proof, verification results and map version identifier to obtain the state transition summary. If any verification fails, a transmission blocking command is output to the data sender, and the failed verification item, plot identifier, crop batch identifier, and data collection time are written to the blockchain.

5. The method for encrypted transmission of agricultural blockchain data for the digital economy according to claim 1, characterized in that, The process of decomposing agricultural raw data into a basic data layer and a progressive residual layer includes: Based on the data type of the agricultural raw data, data precision levels are set in ascending order, with each data precision level corresponding to a defined time sampling interval and spatial grid size. The raw agricultural data is aggregated according to the time sampling interval and spatial grid size of the lowest data precision level to generate the basic data layer. Agricultural data is reconstructed according to the first level of data precision, and the difference between the target data of the first level of data precision and the reconstruction result of the basic data layer is determined as the first progressive residual layer. For subsequent data precision levels, the difference between the target data of the current data precision level and the superimposed reconstruction results of the basic data layer and the preceding progressive residual layer is determined as the current progressive residual layer; Stop generating progressive residual layers with hierarchical indices greater than the highest data precision level.

6. The method for encrypted transmission of agricultural blockchain data for the digital economy according to claim 3, characterized in that, The layered ciphertext transmission unit includes: Obtain the root key stored in the key management node, and combine the state transition summary, plot identifier, crop batch identifier, data type identifier, and the current data layer hierarchy identifier into the current key derivation parameters; The root key and the current key derivation parameters are processed by the key derivation function to generate the layer key for the current data layer; An authentication encryption algorithm is used to encrypt the current data layer using the layer key of the current data layer, resulting in the ciphertext of the current data layer and the authentication tag. Write the basic data layer ciphertext, authentication tag, and hierarchy identifier into the hierarchical ciphertext transmission unit corresponding to the basic data layer; Write the ciphertext of the progressive residual layer, the authentication tag, the level identifier, and the ciphertext digest of the previous layer ciphertext transmission unit into the layered ciphertext transmission unit corresponding to the progressive residual layer, so as to form a ciphertext digest chain from the basic data layer to the highest progressive residual layer.

7. The method for encrypted transmission of agricultural blockchain data for the digital economy according to claim 5, characterized in that, The generated reconstruction error commitment includes: Data reconstruction is performed using the basic data layer and the combination of data layers consisting of the basic data layer and the continuously progressive residual layer, respectively, to obtain reconstructed data corresponding to each data precision level. Calculate the root mean square error between the reconstructed data and the original agricultural data, and normalize the root mean square error by the effective range difference of the corresponding data type to obtain the dimensionless reconstruction error. The dimensionless reconstruction error, data precision level, ciphertext digest of the corresponding hierarchical ciphertext transmission unit, and random commitment parameters are concatenated in a fixed field order to obtain the error commitment payload. The error commitment load is hashed to generate the reconstructed error commitment; Each reconstruction error commitment is associated with its corresponding data precision level, hierarchical encrypted transmission unit index, and state transition summary and written into the blockchain.

8. The method for encrypted transmission of agricultural blockchain data for the digital economy according to claim 7, characterized in that, The verification of data accuracy rights certificates via smart contracts includes: Read the recipient's identity identifier, land parcel identifier, crop batch identifier, transaction batch identifier, authorization start time, authorization end time, authorized data purpose, and authorization precision level from the data precision rights certificate; The fields in the data precision rights certificate are matched item by item with the access policies in the blockchain, and the request precision level, the authorization precision level and the highest data precision level are compared. When the fields match, the current time is between the authorization start time and the authorization end time, and the requested precision level is not higher than the authorization precision level and the highest data precision level, determine the target data layer from the basic data layer to the requested precision level. The threshold secret sharing method is used to decompose the layer key of each target data layer into multiple key shares, and the smart contract specifies the key management node that can provide key shares to the verified recipient.

9. The method for encrypted transmission of agricultural blockchain data for the digital economy according to claim 8, characterized in that, The receiver decrypts and overlays data layers in hierarchical order, including: Obtain the key share that has reached the threshold from the key management node, and reconstruct the layer key for each target data layer; Read the hierarchical encrypted transmission units in ascending order of hierarchical identifiers and verify the authentication tags in each hierarchical encrypted transmission unit; For the progressive residual layer, the ciphertext digest of the previous layer ciphertext transmission unit is calculated, and the calculation result is compared with the ciphertext digest of the previous layer recorded in the current layer ciphertext transmission unit. When both the authentication tag and the pre-layer ciphertext digest are verified, the data layer ciphertext is decrypted using the corresponding layer key. The plaintext of the basic data layer is used as the initial recovery data. The plaintext of each progressive residual layer is aligned according to the time sampling position and spatial grid position, and then superimposed on the initial recovery data in sequence to obtain the recovery data corresponding to the requested precision level.

10. The method for encrypted transmission of agricultural blockchain data for the digital economy according to claim 8, characterized in that, The verification of the recovered data based on the reconstruction error commitment includes: Based on the transaction batch identifier and the request precision level, the corresponding reconstruction error commitment, the ciphertext digest of the layered ciphertext transmission unit, and the error limit are read from the blockchain; Calculate the actual root mean square error between the recovered data and the transaction verification data, and normalize it using the effective range difference of the data type to which the transaction verification data belongs, to obtain the actual reconstruction error; Obtain the random commitment parameter corresponding to the reconstruction error commitment, and concatenate the actual reconstruction error, the requested precision level, the ciphertext digest of the hierarchical ciphertext transmission unit, and the random commitment parameter according to the fixed field order and perform hash calculation to obtain the commitment to be verified. When the commitment to be verified is consistent with the on-chain reconstruction error commitment and the actual reconstruction error is not higher than the error limit, the smart contract generates data delivery confirmation information and executes transaction settlement. If the commitment to be verified is inconsistent with the on-chain reconstruction error commitment, or if the actual reconstruction error exceeds the error limit, transaction settlement will be suspended, and the transaction batch identifier, request precision level, actual reconstruction error, and state transition summary will be written into the data delivery anomaly record.

Images