Linear communication complexity consensus method based on DAG structure

Abstract

The invention discloses a linear communication complexity consensus method based on a DAG structure, and belongs to the field of computer science and technology. According to the invention, an efficient BFT consensus method is established by optimizing a communication process and introducing a broadcast mode of linear communication complexity. According to the invention, a broadcast mode (VBC) with linear communication complexity is introduced to replace the traditional reliable broadcast (RBC), so that the communication complexity is greatly reduced, and the efficiency of the system is improved; in addition, the communication complexity is effectively reduced, the system can process more transactions, the throughput of the system is remarkably improved, and the requirement of large-scale application is met; furthermore, a broadcast mode (VBC) with linear communication complexity enables the communication overhead not to be obviously increased when the number of nodes of the system is increased, so that the expandability of the system is improved, and the method is suitable for a larger-scale distributed network; and finally, by combining a distributed hash table and a threshold signature technology, the system can still maintain high-level security and fault tolerance and prevent attack of malicious nodes while the communication complexity is reduced, the throughput of the system can be remarkably improved, the expandability of the BFT consensus system in large-scale application can be realized, and the method is suitable for popularization and application. Therefore, a major breakthrough is brought to the development of a distributed system and a block chain technology.

Description

Technical Field

[0001] The present invention relates to the field of computer science and technology, and in particular to a linear communication complexity consensus method based on a DAG structure. Background Art

[0002] The Byzantine Fault Tolerant (BFT) consensus mechanism is a key technology in distributed systems, especially in the field of blockchain. The main goal of the BFT consensus mechanism is to ensure the consistency of multiple copies in the system, so that the system can still operate normally even in the presence of malicious or faulty nodes. Traditional BFT consensus protocols usually rely on reliable broadcast (RBC) to achieve data consistency, but this method has a high communication complexity, which limits the scalability and performance of the system.

[0003] In order to improve the parallel processing capability of the BFT consensus protocol, the directed acyclic graph (DAG) structure was introduced into the design of the BFT consensus protocol, forming a DAG-based BFT consensus protocol. Existing DAG-based BFT protocols usually run in continuous waves, each of which contains three to four reliable broadcast (RBC) steps to broadcast data. Since each RBC step requires three communication phases and the communication complexity of each phase is O(N 2 ), which leads to a significant increase in the overall communication complexity.

[0004] Currently, the high communication complexity of DAG consensus protocols is mainly attributed to the reliable broadcast (RBC) mechanism. Therefore, in order to reduce the communication complexity, we propose a new broadcast method - broadcast with linear communication complexity (VBC) to replace the traditional RBC. The introduction of VBC aims to significantly reduce the communication steps and complexity, thereby improving the efficiency and scalability of the system. However, simply replacing RBC with VBC may bring new challenges, especially in terms of the security and liveness of the consensus.

[0005] Based on the above content, the present invention proposes a linear communication complexity consensus method based on DAG structure to solve the above problems. Summary of the invention

[0006] 1. Technical Problems to be Solved by the Present Invention

[0007] The purpose of the present invention is to propose a linear communication complexity consensus method based on DAG structure to solve the problem raised in the background technology. The present invention establishes an efficient BFT consensus method by optimizing the communication process and introducing a broadcast method with linear communication complexity. The present invention can not only significantly improve the throughput of the system, but also realize the scalability of the BFT consensus system in large-scale applications, thus bringing a major breakthrough to the development of distributed systems and blockchain technology.

[0008] 2. Technical solution

[0009] To achieve the above object, the present invention provides the following technical solutions:

[0010] A linear communication complexity consensus method based on a DAG structure. Assuming that the system to which the consensus method is applied includes n nodes and f Byzantine nodes, the specific implementation process is as follows:

[0011] S1. Collect transaction information and distribute all transaction information;

[0012] S2, based on the distribution results of S1, organize the obtained transaction plaintext and hash into a DAG graph for subsequent consensus;

[0013] S3. Design and introduce a new consensus protocol to determine which transactions in the DAG graph obtained in S2 will be submitted.

[0014] Preferably, the S1 specifically includes the following contents:

[0015] S1.1. The client hashes the transaction plaintext and then uses the distributed hash table algorithm to calculate the f+1 nodes to be sent.

[0016] S1.2. The client submits a transaction to the memory pool, which consists of a group of workers and a primary.

[0017] S1.3. Use the worker to package the transaction into a batch, and the worker sends the hash of the batch to the primary;

[0018] S1.4. Use the primary to receive the hash from the worker.

[0019] S1.5. Generate a certificate and use VBC to broadcast and collect threshold signatures.

[0020] Preferably, S2 specifically includes the following contents:

[0021] S2.1. After receiving the transaction hash, the primary verifies the transaction;

[0022] S2.2. If the transaction is verified, it will be added to the DAG local graph of the corresponding round;

[0023] S2.3. If more than 2f+1 transaction hashes are received in each round, proceed to the next round.

[0024] Preferably, the submission process of the consensus protocol described in S3 specifically includes the following contents:

[0025] S3.1. Generate blocks and broadcast them;

[0026] S3.2. Each validator references these blocks;

[0027] S3.3. Select a random coin to select the block leader in the first step;

[0028] S3.4. If the block to be submitted generated in the first step is referenced by f+1 blocks in the second step, then the block is submitted.

[0029] 3. Beneficial effects

[0030] (1) Reduced communication complexity: The present invention introduces a broadcast mode with linear communication complexity (VBC) to replace the traditional reliable broadcast (RBC), which greatly reduces the communication complexity and thus improves the efficiency of the system;

[0031] (2) Improved system throughput: The present invention effectively reduces the complexity of communication, and the system can process more transactions, significantly improving the system throughput and meeting the needs of large-scale applications;

[0032] (3) Enhanced scalability: The broadcast method with linear communication complexity (VBC) ensures that the communication overhead does not increase significantly when the number of nodes increases, thereby improving the scalability of the system and making it suitable for larger-scale distributed networks.

[0033] (4) Maintaining consensus security and activity: The present invention combines distributed hash tables and threshold signature technology to ensure that while reducing communication complexity, the system can still maintain a high level of security and fault tolerance to prevent attacks from malicious nodes.

[0034] In summary, the present invention reduces the communication complexity of DAG consensus from the traditional O(N 2 ) is reduced to linear complexity, which significantly improves the performance and scalability of the system and provides important technical support for the development of distributed systems and blockchain technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a schematic diagram of the memory pool packaging method proposed by the present invention;

[0036] Figure 2 A schematic diagram of forming a DAG graph proposed by the present invention;

[0037] Figure 3 This is a schematic diagram of the consensus block flow proposed in the present invention. DETAILED DESCRIPTION

[0038] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0039] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0040] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0041] See also Figure 1-3 , the present invention proposes a linear communication complexity consensus method based on DAG structure, which specifically includes the following contents:

[0042] Assuming that the system in which the consensus method is applied includes n nodes and f Byzantine nodes, the specific implementation process is as follows:

[0043] S1. Collect transaction information and distribute all transaction information, including the following:

[0044] S1.1. The client hashes the transaction plaintext and then uses the distributed hash table algorithm to calculate the f+1 nodes to be sent.

[0045] S1.2. The client submits a transaction to the memory pool, which consists of a group of workers and a primary.

[0046] S1.3. Use the worker to package the transaction into a batch, and the worker sends the hash of the batch to the primary;

[0047] S1.4. Use the primary to receive the hash from the worker.

[0048] S1.5. Generate a certificate and use VBC to broadcast and collect threshold signatures;

[0049] S2. Based on the distribution results of S1, the obtained transaction plaintext and hash are organized into a DAG graph for subsequent consensus, which specifically includes the following contents:

[0050] S2.1. After receiving the transaction hash, the primary verifies the transaction;

[0051] S2.2. If the transaction is verified, it will be added to the DAG local graph of the corresponding round;

[0052] S2.3. If more than 2f+1 transaction hashes are received in each round, the next round will be entered;

[0053] S3. Design and introduce a new consensus protocol to determine which transactions in the DAG graph obtained in S2 will be submitted. The submission process of the consensus protocol specifically includes the following contents:

[0054] S3.1. Generate blocks and broadcast them;

[0055] S3.2. Each validator references these blocks;

[0056] S3.3. Select a random coin to select the block leader in the first step;

[0057] S3.4. If the block to be submitted generated in the first step is referenced by f+1 blocks in the second step, then the block is submitted.

[0058] The linear communication complexity consensus method based on DAG structure proposed by the present invention is described below with reference to specific examples and drawings. The specific contents are as follows.

[0059] Embodiment 1:

[0060] 1. System architecture design:

[0061] DAG structure: Directed Acyclic Graph (DAG) is used as the data structure to ensure the order and consistency of transactions.

[0062] Distributed Hash Table (DHT): Use the DHT algorithm to calculate the target node of the transaction to ensure efficient distribution of transactions.

[0063] Threshold signature: Combined with threshold signature technology, it ensures the security and fault tolerance of the system.

[0064] 2. Transaction processing flow:

[0065] Transaction reception: The client submits the transaction to the node, and the node adds the received transaction to the transaction pool.

[0066] Transaction packaging: When the gossip heartbeat detects that a gossip needs to be initiated, the node creates a new event, packages all transactions in the transaction pool into the event, and then inserts it into the storage.

[0067] 3. Event propagation and merging:

[0068] Event propagation: select a node, initiate VBC propagation, and collect threshold signatures

[0069] Event merging: After receiving the events returned by the other party, merge the events and add them to the events in the pending area, and then divide them into rounds.

[0070] 4. Consensus reached:

[0071] Round 1: Generate blocks and broadcast them.

[0072] Round 2: Validators vote on blocks (i.e., reference them).

[0073] Round 3: A random coin is selected to select the block leader of Round 1.

[0074] Block submission: The block to be submitted generated in Round 1 is submitted if there are f+1 blocks that reference this block in Round 2.

[0075] 5. Transaction block entry and verification:

[0076] Transaction block entry: Take out the new consensus event, pack the transactions into a block, and clear the pending area.

[0077] Block verification: Return the block to the blockchain, execute the transactions in the block, and return the ledger status to the DAG. The DAG blocks the ledger status, signs it, and broadcasts the signature to other nodes. After receiving the signature, other nodes verify that it is correct, merge it with their own signature, and then broadcast their own signature.

[0078] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and improved concepts of the present invention within the technical scope disclosed by the present invention, and they should be covered by the protection scope of the present invention.

Claims

1. A linear communication complexity consensus method based on DAG structure, characterized in that: Assuming that the system in which the consensus method is applied includes n nodes and f Byzantine nodes, the specific implementation process is as follows: S1. Collect transaction information and distribute all transaction information; S2, based on the distribution results of S1, organize the obtained transaction plaintext and hash into a DAG graph for subsequent consensus; S3. Design and introduce a new consensus protocol to determine which transactions in the DAG graph obtained in S2 will be submitted.

2. According to claim 1, a linear communication complexity consensus method based on DAG structure is characterized in that: The S1 specifically includes the following contents: S1.

1. The client hashes the transaction plaintext and then uses the distributed hash table algorithm to calculate the f+1 nodes to be sent. S1.

2. The client submits a transaction to the memory pool, which consists of a group of workers and a primary. S1.

3. Use the worker to package the transaction into a batch, and the worker sends the hash of the batch to the primary; S1.

4. Use the primary to receive the hash from the worker. S1.

5. Generate a certificate and use VBC to broadcast and collect threshold signatures.

3. According to claim 2, a linear communication complexity consensus method based on DAG structure is characterized in that: The S2 specifically includes the following contents: S2.

1. After receiving the transaction hash, the primary verifies the transaction; S2.

2. If the transaction is verified, it will be added to the DAG local graph of the corresponding round; S2.

3. If more than 2f+1 transaction hashes are received in each round, proceed to the next round.

4. According to claim 3, a linear communication complexity consensus method based on DAG structure is characterized in that: The submission process of the consensus protocol described in S3 specifically includes the following: S3.

1. Generate blocks and broadcast them; S3.

2. Each validator references these blocks; S3.

3. Select a random coin to select the block leader in the first step; S3.

4. If the block to be submitted generated in the first step is referenced by f+1 blocks in the second step, then the block is submitted.

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