A blockchain hybrid consensus method and system based on an asynchronous committee

Abstract

The application discloses a kind of based on asynchronous committee's blockchain hybrid consensus method and system, the method includes: by the election processing of several block nodes in blockchain system through Nakamoto consensus algorithm, obtain committee node and ordinary node;Ordinary node carries out checking processing according to the transaction information of client, obtains block;According to block, committee node carries out consensus processing through executing asynchronous consensus protocol, obtains block consensus result.The embodiment of the application can reduce the overall energy consumption of blockchain system and improve the reliability of blockchain system in complex network environment.The application is a kind of based on asynchronous committee's blockchain hybrid consensus method and system, and can be widely applied in blockchain technology field.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of blockchain, in particular to a blockchain hybrid consensus method and system based on an asynchronous committee. BACKGROUND

[0002] As a kind of decentralized distributed ledger system, the core of blockchain technology is the design of consensus mechanism. The related consensus mechanism has the following problems, although the proof of work (PoW) mechanism has good decentralization characteristics, there is a serious performance bottleneck. The PoW system represented by Bitcoin requires a large number of hash calculations by all nodes, which not only causes huge energy waste, but also leads to low transaction processing efficiency due to long block confirmation time (Bitcoin average 10 minutes). In addition, the inherent fork possibility of PoW mechanism makes the transaction need to wait for multiple confirmations to ensure safety, which further prolongs the confirmation time. To solve the efficiency problem of PoW, proof of stake (PoS) and delegated proof of stake (DPoS) mechanisms are proposed. Although these mechanisms improve efficiency, they are prone to concentrate wealth, affecting the degree of decentralization of the system. At the same time, these mechanisms also face security threats such as "no stake". Traditional Byzantine fault tolerance (BFT) consensus protocols such as PBFT, Tendermint, etc. can provide immediate finality, but they rely on strong network synchronization assumptions and are difficult to run reliably in actual Internet environments. In addition, these protocols usually require multiple rounds of communication between nodes, and the performance decreases sharply when the number of nodes increases, making it difficult to support large-scale node networks. SUMMARY

[0003] To solve the above technical problems, the purpose of the present application is to provide a blockchain hybrid consensus method and system based on an asynchronous committee, which can reduce the overall energy consumption of the blockchain system and improve the reliability of the blockchain system in complex network environments.

[0004] The first technical solution adopted by the present application is: a blockchain hybrid consensus method based on an asynchronous committee, comprising the following steps:

[0005] The committee nodes and ordinary nodes are obtained by electing a number of block nodes in the blockchain system through the Nakamoto consensus algorithm.

[0006] The ordinary nodes perform calculation processing on the transaction information of the client to obtain a block.

[0007] According to the block, the committee nodes perform consensus processing through the execution of an asynchronous consensus protocol to obtain a block consensus result.

[0008] Further, the step of obtaining committee nodes and common nodes by electing a plurality of block nodes in the blockchain system through the Nakamoto consensus algorithm specifically comprises:

[0009] Obtaining a plurality of block nodes in the blockchain system;

[0010] Performing weight amplitude processing on the block nodes according to corresponding parameter information of the block nodes to obtain block nodes with weights, wherein the parameter information includes online time and coin holding amount;

[0011] Performing election voting on the block nodes with weights through the Nakamoto consensus algorithm, and selecting the top N block nodes with the highest weights as committee nodes, and the remaining nodes as common nodes.

[0012] Further, each committee node is replaced after serving a term of office epoch, wherein the term of office epoch includes a plurality of preset block rotation time points.

[0013] Further, the step of obtaining a block by performing verification processing on transaction information of a client by the common node specifically comprises:

[0014] Storing transaction information broadcasted by a client in the network to the blockchain network to construct a transaction pool;

[0015] Packing transactions in the transaction pool by the common node to obtain corresponding hash calculation values and obtain a block.

[0016] Further, the block includes a block header, a block body, consensus verification information, and additional information, wherein:

[0017] The block header includes a block height, a hash value of a parent block, a committee member list, a block generator, and a block hash;

[0018] The block body includes information of a transaction list, PoW proof information, and block content summary information, wherein the information of the transaction list is packed into the block by a generation node of the block;

[0019] The consensus verification information includes signature information of the block by the committee nodes in the consensus process, wherein the consensus nodes verify the correctness of the block and the correctness of each transaction one by one, sign the block hash with a private key, and then attach it to the consensus verification information part, so that the block is officially added to the blockchain after reaching consensus;

[0020] The additional information is used to replace the committee or record reward information.

[0021] Further, the step of obtaining a block consensus result by performing consensus processing on the block by the committee node through an asynchronous consensus protocol specifically comprises:

[0022] Obtaining a hash value of the block as input data;

[0023] According to the dimension characteristics of the transaction, the corresponding asynchronous consensus is selected;

[0024] If the dimension characteristics of the transaction is to focus on the safety of the transaction, a message authentication mechanism is selected to perform consensus processing on the input data to obtain a first block consensus result;

[0025] If the dimension characteristics of the transaction is to focus on the efficiency of the transaction, a lightweight cryptography primitive mechanism is selected to perform consensus processing on the input data to obtain a second block consensus result;

[0026] Integrating the first block consensus result and the second block consensus result to obtain a block consensus result.

[0027] Further, the block consensus result is broadcasted to all nodes of the blockchain by the consensus node as the latest block of the blockchain.

[0028] The second technical solution adopted by the application is: a blockchain hybrid consensus system based on an asynchronous committee, comprising:

[0029] The first module is used for performing election processing on a plurality of block nodes in the blockchain system through the Nakamoto consensus algorithm to obtain committee nodes and ordinary nodes;

[0030] The second module is used for performing verification processing on the block according to the transaction information of the client by the ordinary node;

[0031] The third module is used for performing consensus processing on the block by the committee node through the execution of an asynchronous consensus protocol to obtain a block consensus result.

[0032] The beneficial effects of the method and system of the application are: the Nakamoto consensus algorithm is used to perform election processing on a plurality of block nodes in the blockchain system to obtain committee nodes and ordinary nodes, further, the ordinary node performs verification processing on the block according to the transaction information of the client, the higher difficulty PoW is used in the first layer to perform election of committee members, the lower difficulty PoW is used in the second layer to generate ordinary blocks, which significantly reduces the overall energy consumption of the system, and maintains the decentralized characteristics of PoW, and further provides fast block confirmation capability through the committee mechanism, finally, the committee node performs consensus processing on the block through the execution of an asynchronous consensus protocol to obtain a block consensus result, the asynchronous consensus protocol adopted by the committee does not need to make any assumption on network synchronization, and the reliability of the system in a complex network environment is improved. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1is a step flow chart of a blockchain hybrid consensus method based on an asynchronous committee according to the present application;

[0034] Figure 2 is a structural block diagram of a blockchain hybrid consensus system based on an asynchronous committee according to the present application;

[0035] Figure 3 is a protocol architecture schematic diagram of a blockchain hybrid consensus provided by an embodiment of the present application;

[0036] Figure 4 is an algorithm composition schematic diagram of a consensus mechanism provided by an embodiment of the present application;

[0037] Figure 5 is a flow schematic diagram of a blockchain hybrid consensus protocol provided by an embodiment of the present application;

[0038] Figure 6 is a flow schematic diagram of a protocol according to rounds provided by an embodiment of the present application;

[0039] Figure 7 is a block composition structure schematic diagram provided by an embodiment of the present application;

[0040] Figure 8 is a schematic diagram of a consensus node mechanism within a committee provided by an embodiment of the present application;

[0041] Figure 9 is a schematic diagram of a transaction pool Txpool provided by an embodiment of the present application;

[0042] Figure 10 is a schematic diagram of a consensus based on block-based hash provided by an embodiment of the present application. DETAILED DESCRIPTION

[0043] The present application will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. For the step numbers in the following embodiments, they are only set for the convenience of description and explanation, and the order between the steps is not limited in any way, and the execution order of each step in the embodiments can be adaptively adjusted according to the understanding of those skilled in the art.

[0044] First of all, it needs to be pointed out that, compared with the prior art, the traditional blockchain consensus mechanism either relies on the computationally intensive PoW mechanism, leading to energy waste and confirmation delay, or relies on the BFT protocol that needs strong network synchronization assumption, which is difficult to reliably run in a real network environment. While the present application successfully solves these problems through hybrid consensus design: first, only high-difficulty PoW is used in the committee election stage, significantly reducing the overall energy consumption of the system; second, the asynchronous consensus protocol used by the committee does not require any assumption about network synchronization, improving the reliability of the system in complex network environments; finally, the deterministic nature of the committee consensus result avoids blockchain forks, providing reliable finality guarantees for upper-layer applications.

[0045] Specifically, the present application adopts a two-layer proof-of-work mechanism, using higher-difficulty PoW in the first layer to elect committee members and lower-difficulty PoW in the second layer to generate ordinary blocks. Committee members are responsible for executing an asynchronous consensus protocol, validating blocks generated by ordinary nodes, and generating verifiable consensus proofs. This layered design maintains the decentralized nature of PoW while providing fast block confirmation capabilities through the committee mechanism.

[0046] Based on this, as Figure 3 shown, the protocol of the present application is applicable in a blockchain public chain environment, where nodes can enter or leave the system at will. Transaction information is sent to all nodes by a separate client. All nodes in the blockchain are divided into two parts: committee nodes and ordinary nodes. The consensus algorithm uses a combination of Nakamoto consensus and distributed asynchronous algorithm. Ordinary nodes are responsible for packaging transactions and performing PoW verification to generate blocks; consensus nodes belong to the consensus committee and are responsible for validating blocks mined by ordinary nodes, including checking for conflicting transactions, correct format, correct signature, etc., and reaching a consensus at a certain block height to save the latest block in the current blockchain. The generation of each block is a consensus round, and to avoid frequent view changes, each blockchain committee has an epoch, which contains multiple consensus rounds.

[0047] Referring to Figure 1 , the present application provides a hybrid consensus method for a blockchain based on an asynchronous committee, which includes the following steps:

[0048] S100, a number of block nodes in the blockchain system are processed by a Nakamoto consensus algorithm to obtain committee nodes and ordinary nodes;

[0049] Specifically, a plurality of block nodes in a blockchain system are acquired; weight amplitude processing is performed on the block nodes according to corresponding parameter information of the block nodes, to obtain block nodes with weights, the parameter information including online time and coin holding amount; and the block nodes with weights are subjected to voting by a Nakamoto consensus algorithm, to select the top N block nodes with the highest weights as committee nodes, and the remaining nodes as common nodes.

[0050] S200, the common node performs checking processing on the transaction information of the client to obtain a block.

[0051] Specifically, transaction information broadcast by a client in a network to the blockchain network is stored to construct a transaction pool; and the common node packages the transaction information in the transaction pool to obtain corresponding hash calculation values and obtain a block.

[0052] In this embodiment, as shown in Figure 4 , the computing power is the basis for each node to continuously run the protocol. Similar to the checking process of Bitcoin, the common node generates a new block by solving a hash puzzle and submits it to the current committee for consensus. This hash puzzle is difficult to solve but fast to verify, so the committee nodes can quickly verify these blocks and take the verified blocks as their own consensus proposals.

[0053] It should be further explained that each block in the blockchain is the result of consensus by each round of consensus committee. Each block is generated by checking by the common node group and is signed by the committee nodes in the consensus process. After the block obtains enough n-f consensus signatures, it is marked as valid and broadcast to all nodes to be recorded in the local account book. In this protocol, the block is composed of four parts, including the block header, the block body, the consensus verification information and the additional information. As shown in Figure 7 , the block header contains information such as block height, hash value of parent block, committee member list, block generator, block hash, etc. The block body contains information of the transaction list, which is packaged into the block by the block generation node, as well as PoW proof, block content digest, etc. The consensus verification information contains the signature information of the committee nodes on the block in the consensus process. The consensus node verifies the correctness of the block and the correctness of each transaction one by one, signs the block hash with the private key, and attaches it to the consensus verification information part, to ensure that the block is officially added to the blockchain after reaching consensus. The additional information is used to replace the committee or record reward information and other processes.

[0054] S300, according to the block, the committee node performs consensus processing by executing an asynchronous consensus protocol to obtain a block consensus result.

[0055] Specifically, the hash value of the block is obtained as input data; according to the dimension feature of the transaction, a corresponding asynchronous consensus device is selected; if the dimension feature of the transaction is to focus on the safety of the transaction, a message authentication mechanism is selected to perform consensus processing on the input data to obtain a first block consensus result; if the dimension feature of the transaction is to focus on the efficiency of the transaction, a lightweight cryptography primitive mechanism is selected to perform consensus processing on the input data to obtain a second block consensus result; and the first block consensus result and the second block consensus result are integrated to obtain a block consensus result.

[0056] In the present embodiment, as shown in Figure 8 , within the committee, the committee nodes will select a certain block received as a consensus node in the current round of consensus according to the rules, as the input of the consensus algorithm, and the output after the consensus algorithm is the consensus result of the current round. The consensus result is the latest block of the blockchain and is broadcast by the consensus node to all nodes of the blockchain.

[0057] As shown in Figure 9 , each committee node has its own transaction pool Txpool and a list of received blocks containing information about the blocks. Different committee nodes may receive different blocks because the ordinary node group uses the PoW consensus algorithm, which may result in forking, and as a result, multiple ordinary nodes have dug out blocks and submitted them to the consensus committee. The consensus nodes in the committee will perform consensus on these blocks, and the consensus result is the only block at this height that is submitted to the blockchain, avoiding forking. Therefore, the present protocol is a deterministic consensus.

[0058] Further, as shown in Figure 10 , the asynchronous consensus protocol is sensitive to the size of the input, so the size of the input of the asynchronous consensus device should be reduced as much as possible. Because the blocks dug out by the nodes are broadcast to all consensus nodes, the consensus nodes often store the specific content of multiple blocks, so only the hash of the corresponding block is used as the input of the asynchronous consensus device for consensus in the consensus process to speed up the consensus process.

[0059] The selection of the asynchronous consensus within the committee is a key flexible point in the application, which can be customized according to the specific application scenarios and needs of the blockchain. Specifically, the selection of asynchronous consensus can be considered from the following dimensions: (1) When the blockchain system pays more attention to security, the asynchronous consensus scheme with the following characteristics can be selected: introducing additional cryptographic proof mechanisms, increasing verification rounds to provide stronger certainty guarantees, and using more stringent message authentication mechanisms, etc. (2) When the blockchain system pays more attention to transaction processing efficiency, the asynchronous consensus scheme with the following characteristics can be selected: optimizing message complexity, reducing communication rounds, adopting batch processing mechanisms to improve parallelism, or using lightweight cryptographic primitives. Therefore, the specific implementation of the asynchronous consensus can choose different paradigms of asynchronous consensus protocols to implement, and the application supports the use of two mainstream asynchronous consensus paradigms: including the BKR paradigm and the CKPS paradigm.

[0060] In summary, as shown in the steps of the embodiment of the application can be summarized as: Figure 5

[0061] 1) All nodes are elected by the Nakamoto consensus PoW with higher difficulty verification, and the committee nodes are elected for the subsequent asynchronous consensus process, and the remaining nodes become ordinary nodes for processing transactions and verifying blocks.

[0062] 2) The ordinary nodes perform a lower difficulty PoW verification process, package the transactions and generate blocks.

[0063] 3) The ordinary nodes submit the generated blocks to the committee member nodes in the protocol.

[0064] 4) The committee nodes perform the asynchronous consensus protocol within the committee to reach consensus on the generated blocks.

[0065] 5) After reaching consensus, the committee nodes broadcast the consensus result to all nodes.

[0066] 6) The protocol proceeds by rounds, and the process of steps 2) to 5) is required for the generation and chaining of each block, which is consensus by the committee nodes and broadcast to all nodes to form a deterministic consensus.

[0067] As shown in the steps of the embodiment of the application can be summarized as: Figure 6 ​As shown, the protocol of the embodiment of the application is the same as the traditional distributed consensus protocol according to rounds, the protocol of the application runs according to rounds, the ordinary node sends its block to all consensus committee nodes, and the consensus result obtained after the consensus in the committee is submitted to the blockchain network and broadcast to all nodes. Each round is a block consensus process, and the consensus result of the round is the latest block on the blockchain. In order to prevent frequent view changes, the leaderless consensus protocol is designed in the internal consensus of the committee, and the consensus committee is replaced every term epoch. Each term epoch contains multiple block rounds of time, and the consensus committee is replaced only when the consensus cannot be promoted due to too many malicious nodes or network reasons.

[0068] In summary, the embodiment of the application has the following differences compared with the traditional consensus mechanism:

[0069] 1) Deterministic consensus: The traditional blockchain public chain consensus PoW realizes a probabilistic consensus mechanism. The consensus of each block is only a probabilistic consensus, and the security depends on the computing power controlled by the malicious party. If the enemy controls more computing power resources, the consensus is no longer secure.

[0070] 2) Faster consensus speed: In the Bitcoin network using PoW consensus, it often takes about an hour to confirm a transaction (because it needs to wait for 6 blocks to probabilistically confirm that the transaction has been submitted to the chain), and the interval and size of the transaction block also limit the throughput of the blockchain. Committee-based consensus protocol is a solution to accelerate the performance of blockchain consensus. It was first implemented by PeerCensus, and since then, it has triggered a research boom in committee-based consensus of blockchain. PeerCensus adopts a PoW+PBFT consensus form, which forms a deterministic consensus (strong consensus) by running a distributed system consistency protocol PBFT in the committee after the probabilistic consensus (weak consensus) in the previous blockchain. The research of committee-based consensus protocol also mostly adopts the form of PoX consensus + distributed system consistency protocol, but is limited to synchronous and semi-synchronous network assumptions.

[0071] 3) More extensive application environment: Considering that the committee nodes may be in a poor environment when applied to public chain environment, the real situation should be asynchronous network, so the traditional committee-based consensus protocol may not be able to proceed under this condition. Attack on the node network may cause the entire system to be paralyzed. The introduction of the committee in the blockchain consensus improves the performance, but also brings other problems, including the risk of centralization, security risk, etc. It is of great significance to design a more practical and efficient committee-based consensus mechanism.

[0072] Therefore, embodiments of the present application have the following advantages compared with traditional consensus mechanisms:

[0073] 1) Significantly reduces the consensus overhead of the entire network, improves the overall efficiency and scalability of the system;

[0074] 2) Still guarantees consensus security in an asynchronous network environment, improving the practicality of the system;

[0075] 3) Through the committee mechanism, fast block confirmation and deterministic finality are achieved;

[0076] 4) Maintains a moderate degree of decentralization while optimizing system performance.

[0077] Referring to Figure 2 A blockchain hybrid consensus system based on an asynchronous committee includes:

[0078] The first module 201 is configured to perform election processing on a plurality of block nodes in the blockchain system through a Nakamoto consensus algorithm to obtain committee nodes and ordinary nodes.

[0079] The second module 202 is configured to perform calculation processing on the ordinary nodes according to transaction information of a client to obtain a block.

[0080] The third module 203 is configured to perform consensus processing on the committee nodes according to the block by executing an asynchronous consensus protocol to obtain a block consensus result.

[0081] The contents in the above method embodiments are applicable to the present system embodiments. The present system embodiments specifically implement the same functions as the above method embodiments, and achieve the same beneficial effects as the above method embodiments.

[0082] The above is a specific description of the preferred implementation of the present application, but the present application is not limited to the above embodiments. Those skilled in the art can make various equivalent modifications or replacements without departing from the spirit of the present application. These equivalent modifications or replacements are all included in the scope defined by the claims of the present application.

Claims

1. An asynchronous committee-based blockchain hybrid consensus method, characterized in that, The method comprises the following steps: electing a plurality of block nodes in a blockchain system through a Satoshi consensus algorithm to obtain committee nodes and common nodes; a common node performs checking processing on transaction information of a client to obtain a block; a hash value of the block is obtained and used as input data; an asynchronous consensus device corresponding to a dimension feature of a transaction is selected; if the dimension feature of the transaction is to focus on the security of the transaction, a message authentication mechanism is selected to perform consensus processing on the input data to obtain a first block consensus result; if the dimension feature of the transaction is to focus on the efficiency of the transaction, a lightweight cryptography primitive mechanism is selected to perform consensus processing on the input data to obtain a second block consensus result; the first block consensus result and the second block consensus result are integrated to obtain a block consensus result. 2.The hybrid consensus method based on asynchronous committee of blockchain according to claim 1, characterized in that, The step of obtaining the committee nodes and the common nodes by electing the plurality of block nodes in the blockchain system through the Satoshi consensus algorithm specifically comprises: obtaining a plurality of block nodes in the blockchain system; performing weight amplitude processing on the block nodes according to corresponding parameter information of the block nodes to obtain block nodes with weights, the parameter information including online time and coin holding amount; electing the block nodes with the weights through the Satoshi consensus algorithm to select the top N block nodes with the highest weights as the committee nodes, and the remaining nodes as the common nodes. 3.The hybrid consensus method based on asynchronous committee of blockchain according to claim 2, characterized in that, Each committee node is replaced after serving a term of epoch, the term of epoch including a plurality of preset block rotation time points. 4.The hybrid consensus method based on asynchronous committee of blockchain according to claim 3, characterized in that, The step of obtaining the block by the common node performing checking processing on the transaction information of the client specifically comprises: storing transaction information broadcasted by a client in a network to a blockchain network to construct a transaction pool; packaging transactions in the transaction pool by the common node to obtain corresponding hash calculation values and obtain the block. 5.The hybrid consensus method based on asynchronous committee of blockchain according to claim 4, characterized in that, The block comprises a block header, a block body, consensus verification information and additional information, wherein: the block header comprises a block height, a hash value of a parent block, a committee member list, a block generator and a block hash; the block body comprises information of a transaction list, PoW proof information and block content summary information, the information of the transaction list being packaged into the block by a generation node of the block; the consensus verification information comprises signature information of the block by committee nodes in a consensus process, wherein the consensus nodes verify the correctness of the block and the correctness of transactions one by one, sign the block hash with a private key, and are attached to the consensus verification information part, so that the block is ensured to be officially added to the blockchain after reaching a consensus; the additional information is used to replace the committee or record reward information. 6.The hybrid consensus method based on asynchronous committee of blockchain according to claim 5, characterized in that, The block consensus result is broadcasted to all nodes of the blockchain by a consensus node as a latest block of the blockchain.

7. An asynchronous committee-based blockchain hybrid consensus system, characterized in that, The method comprises the following modules: a first module for obtaining the committee nodes and the common nodes by electing the plurality of block nodes in the blockchain system through the Satoshi consensus algorithm; a second module for obtaining the block by the common node performing checking processing on the transaction information of the client; a third module for obtaining the hash value of the block and using the hash value as the input data; According to the dimension feature of the transaction, a corresponding asynchronous consensus device is selected; If the dimension feature of the transaction is to focus on the safety of the transaction, a message authentication mechanism is selected to perform consensus processing on the input data to obtain a first block consensus result; If the dimension feature of the transaction is to focus on the efficiency of the transaction, a lightweight cryptography primitive mechanism is selected to perform consensus processing on the input data to obtain a second block consensus result; The first block consensus result and the second block consensus result are integrated to obtain a block consensus result.

Images