Data cooperative transmission method and system under opportunity network

Abstract

The invention provides a data cooperative transmission method and system under an opportunity network, and relates to the technical field of data cooperative transmission, and the method specifically comprises the steps: collecting key parameters from each node regularly, calculating an effective bandwidth evaluation value and a priority adjustment value of each node, and selecting an optimal transmission path according to the priority adjustment value; the method comprises the following steps: performing fragmentation processing on data to be transmitted, and performing redundant storage on each data fragment; the sender selects the data fragments to send according to the priority and sends a request to the optimal node, and the receiver feeds back the data fragments to the sender in time after confirming that the data fragments are received; and generating a hash value for each data fragment, and performing integrity verification before data recombination. According to the method, the key parameters are collected, and the effective bandwidth evaluation value and the priority adjustment value of the node are dynamically calculated, so that the transmission path selection accuracy and the data transmission efficiency are improved. By performing redundant storage and hash verification on the data fragments, the integrity and security of the data in the transmission process are ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of collaborative data transmission, and in particular to a collaborative data transmission method and system in an opportunistic network. Background Art

[0002] In modern communication and network technologies, opportunistic networks have attracted extensive attention due to their ability to transmit data in dynamic and temporary network environments. Such networks are usually composed of a large number of mobile nodes whose connectivity and network topology change over time. This feature makes opportunistic networks show great potential in specific scenarios, such as disaster recovery, field exploration, and interpersonal networks. However, despite the advantages of opportunistic networks in terms of flexibility and adaptability, existing technologies still face many challenges in terms of the effectiveness and reliability of data transmission. Specifically, the dynamic changes in network latency, available bandwidth, and storage capacity between nodes directly affect the performance of data transmission, and in practical applications, node priority identification and transmission path selection often rely on static or outdated parameters and cannot respond to changes in network status in a timely manner. This deficiency leads to reduced data transmission efficiency in the network and is prone to data loss or transmission delay, which is contrary to the original design intention of opportunistic networks.

[0003] In addition, the current technical solutions also have obvious shortcomings in dealing with data integrity and security. Although some methods try to ensure the accuracy of data through redundant storage and verification, in opportunistic networks, due to the unstable connection between nodes, it is impossible to guarantee the complete transmission of all data shards during the transmission process. Many existing methods fail to fully consider the timely feedback mechanism of sharded data, and the receiver may not be able to effectively confirm the reception status of each data shard, which makes the reliability of the overall data reconstruction questionable. At the same time, the lack of an effective hash verification mechanism makes there is a risk of tampering or loss during data transmission. Therefore, how to achieve efficient data collaborative transmission in opportunistic networks and ensure data integrity and security is still a technical problem that needs to be solved urgently.

[0004] The above information disclosed in this Background section is only for enhancement of understanding of the background of the present disclosure and therefore it may contain information that does not constitute the prior art that is already known to one of ordinary skill in the art. Summary of the invention

[0005] The purpose of the present invention is to provide a method and system for collaborative data transmission in an opportunistic network to solve the problems raised in the above background technology.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A data collaborative transmission method in an opportunistic network, the specific steps comprising:

[0008] Step 1: regularly collect key parameters from each node, wherein the key parameters are network delay, available bandwidth, available storage capacity and importance rating of data to be transmitted;

[0009] Step 2: Calculate the effective bandwidth evaluation value and priority adjustment value of each node based on the key parameters, and select the best transmission path according to the calculated priority adjustment value; after determining the transmission path, slice the data to be transmitted, and store each data slice redundantly;

[0010] Step 3: During the data transmission process, the sender selects the data shard to send according to the priority and sends the request to the optimal node. After confirming that the data shard has been received, the receiver promptly feeds back to the sender;

[0011] Step 4: Generate a hash value for each data shard and perform integrity verification before data reassembly to ensure that each shard has not been tampered with during transmission.

[0012] Furthermore, the process of periodically collecting key parameters from each node is specifically as follows:

[0013] The network delay of the i-th node is calibrated as L i , the acquisition method is: count all nodes connected to the i-th node, and use the network delay test tool to measure the round-trip time between these nodes and the i-th node, and use the average value of the round-trip time as the network delay of the i-th node;

[0014] Use the network bandwidth test tool to test the bandwidth, record the amount of data transmitted and the time required to transmit the data during the test period, and calculate the available bandwidth according to the following formula:

[0015]

[0016] Among them, B i represents the available bandwidth of node i, that is, the maximum amount of data that node i can transmit in the network, D i is the amount of data successfully transmitted by node i during the test, T i is the time taken by node i to transmit data during the test;

[0017] Obtain the node's storage information through the API, record the node's used storage space and total storage capacity, and calculate the available storage capacity of node i according to the following formula:

[0018]

[0019] Among them, C iis the available storage capacity of node i, is the total storage capacity of node i, is the used storage space of node i;

[0020] Each data packet to be transmitted is evaluated through business rules and manual review to determine the importance rating of the data packet to be transmitted, and the importance rating is denoted as I, I∈[1,10], and is a positive integer, wherein when I=1, it indicates that the current data packet to be transmitted is of the lowest importance, and I=10 indicates that the current data packet to be transmitted is of the highest importance.

[0021] Furthermore, the calculation of the effective bandwidth evaluation value of each node is based on the following formula:

[0022]

[0023] Among them, E i is the effective bandwidth evaluation value of node i, B i represents the available bandwidth of node i, L i is the network delay of node i, m is the adjustment constant, set to 0.1, which is used to adjust the impact of delay on bandwidth;

[0024] Calculate the priority adjustment value of each node processing data packets based on the effective bandwidth evaluation value:

[0025] P ix =I x *E i

[0026] Among them, P ix is the priority adjustment value of the data packet x to be transmitted when node i processes it, I x Refers to the importance rating of the xth data packet to be transmitted, E i is the effective bandwidth evaluation value of node i, and x is the index of the data packet to be transmitted;

[0027] The optimal transmission path is selected according to the priority adjustment value. The Dijkstra algorithm is used to input the effective bandwidth evaluation value and network delay of each node, output the optimal path from the source node to the target node, and select the node with the highest priority adjustment value as part of the transmission path.

[0028] Furthermore, the formula for fragmenting the data packet to be transmitted is as follows:

[0029]

[0030] Where S is the number of data fragments, K is the total size of the data packet to be transmitted, and U is the size of each data fragment;

[0031] At the same time, each data shard is stored redundantly, and each data shard corresponds to three nodes for storage.

[0032] Furthermore, the data transmission process is specifically as follows:

[0033] The data sender uploads each data shard to the best selected node. The formula for sending the request is as follows:

[0034] Send(Q)→R if valid(sender)

[0035] Among them, Q is the data shard, R is the target node, and valid(sender) is the verification function;

[0036] The receiver confirms receipt of the data segment:

[0037] confirm(Q)→valid(R)

[0038] Among them, Q is the data shard and R is the target node.

[0039] Furthermore, the process of generating a hash value for each data shard and performing integrity verification before data reorganization is specifically as follows:

[0040] Choose SHA-256 as the hash function, for the pth data shard Q p , calculate its hash value H p :

[0041] H p =H(Q p )

[0042] Among them, H p Refers to data shard Q p The hash value of

[0043] Store each data shard and its corresponding hash value in a data structure:

[0044] HashTable={(Q p , H p )|p=1,2,…,n}

[0045] Where p is the index of the data shard, and n is the total number of data shards;

[0046] During the transmission process, the data fragments and their corresponding hash values ​​are sent, and before the data is reassembled, the hash values ​​of each data fragment are checked for consistency:

[0047] If H(Q p ) = recorded_hash(Q p), then valid

[0048] The present invention further provides a data collaborative transmission system in an opportunistic network, wherein the data collaborative transmission system in an opportunistic network is used to execute the above-mentioned data collaborative transmission method in an opportunistic network, including:

[0049] A data collection module, used to periodically collect key parameters from each node, wherein the key parameters are network delay, available bandwidth, available storage capacity and importance rating of data to be transmitted;

[0050] The priority and path selection module calculates the effective bandwidth evaluation value and priority adjustment value of each node based on key parameters, and selects the best transmission path according to the calculated priority adjustment value; after determining the transmission path, the data to be transmitted is processed into slices, and each data slice is redundantly stored;

[0051] The data sending module is used for the sender to select data slices for sending according to the priority during the data transmission process, and send the request to the optimal node. After the receiver confirms the receipt of the data slice, it will promptly feedback to the sender;

[0052] The integrity verification module is used to generate a hash value for each data shard and perform integrity verification before data reorganization to ensure that each shard has not been tampered with during transmission.

[0053] Compared with the prior art, the present invention has the following beneficial effects:

[0054] The present invention improves the accuracy of transmission path selection and the efficiency of data transmission by regularly collecting key parameters and dynamically calculating the effective bandwidth evaluation value and priority adjustment value of each node. At the same time, by redundantly storing and hashing data fragments, the integrity and security of data during transmission are ensured. This method not only optimizes the resource utilization of data transmission, but also enhances the adaptability of the network in an uncertain environment, thereby providing a more reliable solution for various application scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 It is a schematic diagram of the overall method flow of the present invention;

[0056] Figure 2 It is a schematic diagram of the overall system module of the present invention. DETAILED DESCRIPTION

[0057] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments.

[0058] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The words "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0059] Example:

[0060] See also Figure 1 , the present invention provides a technical solution:

[0061] A data collaborative transmission method in an opportunistic network, the specific steps comprising:

[0062] Step 1: regularly collect key parameters from each node, wherein the key parameters are network delay, available bandwidth, available storage capacity and importance rating of data to be transmitted;

[0063] In this embodiment, the process of periodically collecting key parameters from each node is specifically as follows:

[0064] The network delay of the i-th node is calibrated as L i , the acquisition method is: count all nodes connected to the i-th node, and use the network delay test tool to measure the round-trip time between these nodes and the i-th node, and use the average value of the round-trip time as the network delay of the i-th node;

[0065] Use the network bandwidth test tool to test the bandwidth, record the amount of data transmitted and the time required to transmit the data during the test period, and calculate the available bandwidth according to the following formula:

[0066]

[0067] Among them, B i represents the available bandwidth of node i, that is, the maximum amount of data that node i can transmit in the network, D i is the amount of data successfully transmitted by node i during the test, T i is the time taken by node i to transmit data during the test;

[0068] Obtain the node's storage information through the API, record the node's used storage space and total storage capacity, and calculate the available storage capacity of node i according to the following formula:

[0069]

[0070] Among them, C i is the available storage capacity of node i, is the total storage capacity of node i, is the used storage space of node i;

[0071] Each data packet to be transmitted is evaluated through business rules and manual review to determine the importance rating of the data packet to be transmitted, and the importance rating is denoted as I, I∈[1,10], and is a positive integer, wherein when I=1, it indicates that the current data packet to be transmitted is of the lowest importance, and I=10 indicates that the current data packet to be transmitted is of the highest importance.

[0072] The advantage of step 1 is that by regularly collecting key parameters, real-time monitoring and dynamic adjustment of the network status are achieved. This real-time and dynamic nature can ensure that in a complex and changeable network environment, the selection of data transmission paths and resource allocation are always in the optimal state, thereby improving the efficiency and reliability of the overall network. Compared with the prior art, step 1 provides a comprehensive and dynamic network status monitoring mechanism. By collecting multi-dimensional key parameters, the network environment can be more accurately evaluated, and then the data transmission path and resource allocation can be optimized. This method not only improves the success rate and efficiency of data transmission, but also reduces possible transmission delays and network congestion. The use of step 1 in this patent solution can significantly promote the overall solution. First, it provides a reliable data basis for the calculation of effective bandwidth evaluation values, priority adjustment and path selection in subsequent steps. Secondly, it makes dynamic adjustment of data transmission possible, so that it can flexibly respond to various changes in the network environment and ensure the efficiency and stability of the data transmission process.

[0073] Step 2: Calculate the effective bandwidth evaluation value and priority adjustment value of each node based on the key parameters, and select the best transmission path according to the calculated priority adjustment value; after determining the transmission path, slice the data to be transmitted, and store each data slice redundantly;

[0074] In this embodiment, the calculation of the effective bandwidth evaluation value of each node is based on the following formula:

[0075]

[0076] Among them, E i is the effective bandwidth evaluation value of node i, B irepresents the available bandwidth of node i, L i is the network delay of node i, m is the adjustment constant, set to 0.1, which is used to adjust the impact of delay on bandwidth;

[0077] Calculate the priority adjustment value of each node processing data packets based on the effective bandwidth evaluation value:

[0078] P ix =I x *E i

[0079] Among them, P ix is the priority adjustment value of the data packet x to be transmitted when node i processes it, I x Refers to the importance rating of the xth data packet to be transmitted, E i is the effective bandwidth evaluation value of node i, and x is the index of the data packet to be transmitted;

[0080] The optimal transmission path is selected according to the priority adjustment value. The Dijkstra algorithm is used to input the effective bandwidth evaluation value and network delay of each node, output the optimal path from the source node to the target node, and select the node with the highest priority adjustment value as part of the transmission path.

[0081] The formula for fragmenting the data packet to be transmitted is as follows:

[0082]

[0083] Among them, S is the number of data slices, K is the total size of the data packet to be transmitted, and U is the size of each data slice; and the size of each data slice ranges from 256 bytes to 16KB, and is dynamically adjusted according to the real-time network status and node capabilities to achieve optimal transmission efficiency and data integrity.

[0084] At the same time, each data shard is stored redundantly, and each data shard corresponds to three nodes for storage.

[0085] The advantage of step 2 is that it can dynamically select the best transmission path by calculating the effective bandwidth evaluation value and priority adjustment value of each node. This process not only takes into account the current network status and the importance of the data, but also reselects the path when the transmission path is not ideal. In addition, data sharding and redundant storage ensure the reliability and fault tolerance of data during transmission. Compared with the prior art, this scheme selects the transmission path through the comprehensive evaluation of the priority adjustment value and the effective bandwidth evaluation value, making the data transmission path more intelligent and efficient. The prior art may only select the path with a single or a few parameters, resulting in the failure to fully utilize network resources and low transmission efficiency. However, this scheme can more flexibly respond to the dynamically changing network environment and improve the success rate and efficiency of data transmission. In this patent scheme, the adoption of step 2 can significantly improve the performance and stability of the overall scheme. By dynamically optimizing the transmission path, it is ensured that the data can be transmitted to the target node in the fastest and most reliable way. At the same time, data sharding processing and redundant storage further enhance the fault tolerance and data integrity during the transmission process, making the entire data collaborative transmission process more efficient and secure.

[0086] Step 3: During the data transmission process, the sender selects the data shard to send according to the priority and sends the request to the optimal node. After confirming that the data shard has been received, the receiver promptly feeds back to the sender;

[0087] In this embodiment, the data transmission process is specifically as follows:

[0088] The data sender uploads each data shard to the best selected node. The formula for sending the request is as follows:

[0089] Send(Q)→R if valid(sender)

[0090] Among them, Q is the data shard, R is the target node, and valid(sender) is the verification function;

[0091] The receiver confirms receipt of the data segment:

[0092] confirm(Q)→valid(R)

[0093] Among them, Q is the data shard and R is the target node.

[0094] The advantage of step 3 is that by selecting data fragments for transmission by priority, the transmission order can be optimized, so that important data can be transmitted first. At the same time, the sender sends the request to the optimal node, and then performs subsequent transmission after receiving confirmation feedback, ensuring the reliability and efficiency of the transmission. In addition, the timely feedback mechanism can quickly adjust the transmission strategy to adapt to the dynamic network environment. Compared with the prior art, step 3 in this scheme significantly improves the reliability and efficiency of data transmission through priority adjustment and feedback confirmation mechanism. The prior art may lack dynamic adjustment and confirmation mechanisms, resulting in a high transmission failure rate. The feedback mechanism of this scheme provides real-time transmission status updates, reduces the risk of transmission failure, and can quickly adjust the transmission path and strategy. In this patent scheme, the adoption of step 3 promotes the optimization and intelligence of the overall data transmission process. Priority adjustment ensures the priority transmission of important data; the feedback mechanism improves the success rate and efficiency of transmission, and enhances the flexibility and adaptability of data transmission.

[0095] Step 4: Generate a hash value for each data shard and perform integrity verification before data reassembly to ensure that each shard has not been tampered with during transmission;

[0096] In this embodiment, the process of generating a hash value for each data fragment and performing integrity verification before data reorganization is specifically as follows:

[0097] Choose SHA-256 as the hash function, for the pth data shard Q p , calculate its hash value H p :

[0098] H p =H(Q p )

[0099] Among them, H p Refers to data shard Q p The hash value of

[0100] Store each data shard and its corresponding hash value in a data structure:

[0101] HashTable={(Q p , H p )|p=1,2,…,n}

[0102] Where p is the index of the data shard, and n is the total number of data shards;

[0103] During the transmission process, the data fragments and their corresponding hash values ​​are sent, and before the data is reassembled, the hash values ​​of each data fragment are checked for consistency:

[0104] If H(Q p) = recorded_hash(Q p ), then valid

[0105] The advantage of step 4 is that by generating a hash value for each data shard and performing integrity verification before data reorganization, it is ensured that each shard has not been tampered with during the transmission process. This approach can not only effectively detect and prevent data tampering, but also quickly identify and handle transmission errors during data reorganization to ensure data integrity and security. Compared with the prior art, step 4 in this solution significantly improves the security and reliability of data transmission by generating hash values ​​and verifying the integrity of data shards. The prior art may lack such a fine-grained integrity verification mechanism, which makes it difficult to timely discover and handle data tampering or transmission errors during data transmission. The hash verification mechanism of this solution provides an efficient and reliable means to ensure the integrity and non-tampering of data during transmission. In this patent solution, the adoption of step 4 can significantly improve the data security and reliability of the overall solution. By generating a hash value for each data shard and performing integrity verification, it is ensured that all data shards have not been tampered with or damaged during transmission. This not only improves the accuracy of data reorganization, but also provides a strong guarantee for the security of data transmission.

[0106] See also Figure 2 , a data cooperative transmission system in an opportunistic network, comprising:

[0107] A data collection module, used to periodically collect key parameters from each node, wherein the key parameters are network delay, available bandwidth, available storage capacity and importance rating of data to be transmitted;

[0108] The priority and path selection module calculates the effective bandwidth evaluation value and priority adjustment value of each node based on key parameters, and selects the best transmission path according to the calculated priority adjustment value; after determining the transmission path, the data to be transmitted is processed into slices, and each data slice is redundantly stored;

[0109] The data sending module is used for the sender to select data slices for sending according to the priority during the data transmission process, and send the request to the optimal node. After the receiver confirms the receipt of the data slice, it will promptly feedback to the sender;

[0110] The integrity verification module is used to generate a hash value for each data shard and perform integrity verification before data reorganization to ensure that each shard has not been tampered with during transmission.

[0111] The above formulas are all dimensionless and numerical calculations. The formula is a formula for the most recent real situation obtained by collecting a large amount of data and performing software simulation. The preset parameters in the formula are set by technicians in this field according to actual conditions.

[0112] The above embodiments may be implemented in whole or in part by software, hardware, firmware or any other combination thereof. When implemented by software, the above embodiments may be implemented in whole or in part in the form of a computer program product. Those skilled in the art may appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein may be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed by hardware or software methods depends on the specific application and design constraints of the technical solution.

[0113] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, and may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0114] The above description is only a specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application.

Claims

1. A data cooperative transmission method in an opportunistic network, characterized in that: The specific steps include: Step 1: regularly collect key parameters from each node, wherein the key parameters are network delay, available bandwidth, available storage capacity and importance rating of data to be transmitted; Step 2: Calculate the effective bandwidth evaluation value and priority adjustment value of each node based on the key parameters, and select the best transmission path according to the calculated priority adjustment value; after determining the transmission path, slice the data to be transmitted, and store each data slice redundantly; Step 3: During the data transmission process, the sender selects the data shard to send according to the priority and sends the request to the optimal node. After confirming that the data shard has been received, the receiver promptly feeds back to the sender; Step 4: Generate a hash value for each data shard and perform integrity verification before data reassembly to ensure that each shard has not been tampered with during transmission.

2. The method for collaborative data transmission in an opportunistic network according to claim 1, characterized in that: The process of regularly collecting key parameters from each node is specifically as follows: The network delay of the i-th node is calibrated as L i , the acquisition method is: count all nodes connected to the i-th node, and use the network delay test tool to measure the round-trip time between these nodes and the i-th node, and use the average value of the round-trip time as the network delay of the i-th node; Use the network bandwidth test tool to test the bandwidth, record the amount of data transmitted and the time required to transmit the data during the test period, and calculate the available bandwidth according to the following formula: Among them, B i represents the available bandwidth of node i, that is, the maximum amount of data that node i can transmit in the network, D i is the amount of data successfully transmitted by node i during the test, T i is the time taken by node i to transmit data during the test; Obtain the node's storage information through the API, record the node's used storage space and total storage capacity, and calculate the available storage capacity of node i according to the following formula: Among them, C i is the available storage capacity of node i, is the total storage capacity of node i, is the used storage space of node i; Each data packet to be transmitted is evaluated through business rules and manual review to determine the importance rating of the data packet to be transmitted, and the importance rating is denoted as I, I∈[1,10], and I is a positive integer, wherein when I=1, it indicates that the current data packet to be transmitted is of the lowest importance, and I=10 indicates that the current data packet to be transmitted is of the highest importance.

3. The method for collaborative data transmission in an opportunistic network according to claim 2, characterized in that: The formula for calculating the effective bandwidth evaluation value of each node is as follows: Among them, E i is the effective bandwidth evaluation value of node i, B i represents the available bandwidth of node i, L i is the network delay of node i, m is the adjustment constant, set to 0.1, which is used to adjust the impact of delay on bandwidth; Calculate the priority adjustment value of each node processing data packets based on the effective bandwidth evaluation value: P ix =I x *E i Among them, P ix is the priority adjustment value of the data packet x to be transmitted when node i processes it, I x Refers to the importance rating of the xth data packet to be transmitted, E i is the effective bandwidth evaluation value of node i, and x is the index of the data packet to be transmitted; The optimal transmission path is selected according to the priority adjustment value. The Dijkstra algorithm is used to input the effective bandwidth evaluation value and network delay of each node, output the optimal path from the source node to the target node, and select the node with the highest priority adjustment value as part of the transmission path.

4. The method for collaborative data transmission in an opportunistic network according to claim 1, characterized in that: The formula for fragmenting the data packet to be transmitted is as follows: Where S is the number of data fragments, K is the total size of the data packet to be transmitted, and U is the size of each data fragment; At the same time, each data shard is stored redundantly, and each data shard corresponds to three nodes for storage.

5. The method for coordinated data transmission in an opportunistic network according to claim 4, characterized in that: The data transmission process is specifically as follows: The data sender uploads each data shard to the best selected node. The formula for sending the request is as follows: Send(Q)→Rifvalid(sender) Among them, Q is the data shard, R is the target node, and valid(sender) is the verification function; The receiver confirms receipt of the data segment: confirm(Q)→valid(R) Among them, Q is the data shard and R is the target node.

6. The method for coordinated data transmission in an opportunistic network according to claim 1, characterized in that: The process of generating a hash value for each data shard and performing integrity verification before data reorganization is specifically as follows: Choose SHA-256 as the hash function, for the pth data shard Q p , calculate its hash value H p : H p =H(Q p ) Among them, H p Refers to data shard Q p The hash value of Store each data shard and its corresponding hash value in a data structure: HashTable={(Q p ,H p )|p=1,2,…,n} Where p is the index of the data shard, and n is the total number of data shards; During the transmission process, the data fragments and their corresponding hash values ​​are sent, and before the data is reassembled, the hash values ​​of each data fragment are checked for consistency: IfH(Q p )=recorded_hash(Q p ),the nvalid 7. A data cooperative transmission system in an opportunistic network, characterized in that: The data collaborative transmission system in an opportunistic network is used to execute the data collaborative transmission method in an opportunistic network according to any one of claims 1 to 6, including: A data collection module, used to periodically collect key parameters from each node, wherein the key parameters are network delay, available bandwidth, available storage capacity and importance rating of data to be transmitted; The priority and path selection module calculates the effective bandwidth evaluation value and priority adjustment value of each node based on key parameters, and selects the best transmission path according to the calculated priority adjustment value; after determining the transmission path, the data to be transmitted is processed in slices, and each data slice is redundantly stored; The data sending module is used for the sender to select data slices for sending according to the priority during the data transmission process, and send the request to the optimal node. After the receiver confirms the receipt of the data slice, it will promptly feedback to the sender; The integrity verification module is used to generate a hash value for each data shard and perform integrity verification before data reorganization to ensure that each shard has not been tampered with during transmission.

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