136 results about "Byzantine fault tolerance" patented technology

The invention discloses a byzantine-fault-tolerant consensus method applied to a block chain. The method comprises the steps of specifying a certain number of right and interest accounts and initial consensus accounts in an initiated block of the block chain; after a consensus process is started, for the height h of a current block, selecting a consensus account to initiate a proposal of a new block according to a fixed random algorithm in a consensus account list; receiving the proposal and voting a block with the height of h by other consensus nodes; within a period of time, if the number of votes exceeds eta 1, representing that a consensus is formed, and starting the consensus of a block with the height of h+1 in the next round; if the number of votes does not exceed eta 1 but exceeds eta 2, representing that the consensus is possibly formed, broadcasting a voting request of the block in the previous round, and continuing to wait for a period of time; and if the number of votes does not exceed eta 2, cancelling the proposal in the round and re-performing the proposal of the new block. Therefore, computing resources can be saved; a large amount of blocks can be continuously generated; and computing power competition is avoided.

The invention provides a method for dynamically changing a consensus node in a practical Byzantine fault tolerant consensus mechanism. The method comprises the following steps: a system administratorinitiates a change request of increasing or decreasing the consensus node to the consensus node as a system-level transaction, and the change request is signed by using a private key of the system administrator; the consensus node verifies the change request, if the verification is successful, a special system transaction head is added to the change request, the change request is broadcast, and each consensus node puts the change request into a priority transaction queue; a new round of consensus operation is performed, a selected proposal node proposes a proposal block including the change request and broadcasts the proposal block to all consensus nodes, all the consensus nodes verify transactions in the proposal block, firstly verify the transaction heads of the transactions, and enter system transaction operation logic rather than smart contracts when a special system transaction head is verified; and after reaching a consensus, the node executes the change request and updates a consensus node set list, and the updated consensus node set list is stored to a local file of the nodes.

Provided is a routing position data secrecy storing and sharing method based on block chains. The routing position data secrecy storing and sharing method includes a data storing method and a data sharing method. The data storing method includes the steps of node configuration, data encryption sending, storage subnetwork verification storing, etc. The data sharing method includes the steps of demand generation, demand response, sharing achievement and the like. The effects of the invention are as follows: through a block chain technology, data sharing is realized through data encryption storage and a decentralized network to solve the problems that data storage parties have no right to use data and users do not have channels to selectively enable personal data to be accessed; local encryption sending is adopted during data storage, service parties store encrypted data, the users themselves save decryption secret keys, and the service parties have no access to original data, so a better data protection effect is achieved; and the block chain technology is adopted during storage, commonly recognized storage is realized through a practical Byzantine fault-tolerant algorithm, workload bottleneck problems of centralized storage are solved, and data is prevented from being tampered.

The invention discloses a block chain fragment storage and query method based on erasure codes. When the block storage reaches a certain threshold, a block is sliced and stored. The method comprises the following steps that firstly, the meta-information of the block file fragments is consented, after the consensus is achieved, the erasure codes are utilized to fragment the block files within thethreshold value into the data blocks and the check blocks, and each node stores one part of the data blocks and the check blocks, so that the storage cost is reduced, and meanwhile, the data fault tolerance under the Bayer fault tolerance is also realized. Besides, when the block files are fragmented, the corresponding index is established, and the corresponding data block or check block can be queried from each node by utilizing the index, so that the block data can be queried efficiently under the condition that the storage space is saved.

The invention discloses a block chain adaptive consensus method based on dynamic authorization and network environment perception; the method comprises the following steps: 1, clustering block chain network nodes according to geological positions, and selecting one authorization representative from the same cluster; 2, allowing the authorization representatives selected from all clusters to form all consensus nodes that verify this transaction, wherein a Byzantium fault tolerance algorithm is employed among the consensus nodes so as to reach a consensus that whether this transaction is established or not; 3, adjusting or re-clustering according to network scale, topology, resource or business type changes; 4, updating authorization representatives in the next deal after one deal is verified. The advantages are that the method can set up a fast and credit synergy mechanism among distributed edge clouds based on block chain, so edge nodes can fast and effectively reach consensus withoutany trust basis, thus solving the low throughput, high time delay and low efficiency problems of a consensus algorithm that uses workload proves as representatives.

The invention provides a permission block chain node access method and apparatus based on PBFT (Practical Byzantine Fault Tolerance). The permission block chain node access method based on PBFT includes the following steps: S110, adding a new permission node; S120, synchronizing the permission node without performing agreement temporally; S130, determining whether the permission node satisfies the requirement of an agreement node, if so, entering the step S150, and if not, entering the step S140; S140, waiting until returning to the step S120; and S150, starting performing agreement transaction as the permission node becomes the agreement node. The permission block chain node access method and apparatus based on PBFT can realize dynamic access of the permission node of the permission block chain in a distributed network which takes PBFT as the agreement protocol, and can guarantee consistence of the node block data of the whole network at the same time, thus having relatively higher practicality, being safe and credible, and being conductive to implementation of the application of the permission block chain.

The invention is based on the REPB consensus of the block chain main chain and the parallel multi-sub-chain, and solves the problems of safety and decentralization by randomly selecting the consensusnode, and has high scalability. Encryption is performed to ensure the security of random values. Parallel processing of multi-linked data is carried out to solve performance problems. Byzantine fault-tolerant mechanism to quickly reach consensus, prevent bifurcation, and solve performance problems. Through an effective fusion of the above four technologies, the problems of decentralization, security and performance in the consensus algorithm are solved.

The invention discloses a Byzantium fault-tolerant consensus optimization method for a block chain. The method comprises the following steps: S1, performing voting weight table initialization; S2, processing transaction; S3, electing a main node; S4, verifying a REQUEST message; S5, broadcasting a PRE-PREPARE message; S6, verifying the PRE-PREPARE message; S7, performing voting; S8, broadcasting the PREPARE message containing a voting value; S9, recording the message and the number of voting to a local log; S10, performing weighted sum on the voting value, and performing nonlinear processing;S11, broadcasting the COMMIT message; S12, verifying the COMMIT message; S13, writing the current block into a local account book, and replying a client. The problem that the method disclosed by the invention is limited in application scene, low in security, needs to consume a large amount of communication resources and is large in system resource consumption in the prior art is solved.

The invention belongs to the technical field of block chains, and discloses a reputation-based PBFT consensus system and method, and a block chain data processing system. The method comprises the steps of designing a lightweight reputation evaluation model, and calculating a mixed reputation value of the node based on node importance and service feedback; selecting a part of nodes of which the reputation values are higher than a threshold value as participants of a classical practical occupancy fault-tolerant consensus mechanism; and running a PBFT consensus mechanism in the participant, achieving a consensus based on a new leader election and transaction verification method, and broadcasting a consensus result. Due to the fact that the classical PBFT consensus mechanism is limited in expandability, consensus is not affected by the network scale. Due to the fact that a node reputation evaluation method and a participant election method are added, the method has higher safety compared with a classical PBFT. The calculated node reputation can guide the next transaction, so that the computing power for evaluating the node reputation is effective computing power.

The present invention provides a complex digital asset-orientated multi-stage PBFT (Practical Byzantine Fault Tolerance) consensus system and method. The complex digital asset-orientated multi-stage PBFT (Practical Byzantine Fault Tolerance) consensus system includes a transaction checker, a primary node self-checker, a transaction batch consensus device, a view rotator, a consensus message processor and a block builder; the transaction checker completes transaction-related consistency and security check during a commit phase; the primary node self-checker performs processing in a ViewChange message processing process; the transaction batch consensus device is responsible for batch processing of a plurality of transactions; the view rotator is used for completing the selection of a primarynode, the update of a new round of view and the recording of the information of a last view in a ViewChange protocol process so as to ensure the continuity of a new view; the consensus message processor achieves the global consistency of messages through a consensus processes at different stages; and the block builder can complete block-related transaction submission and sorting, as well as blockconstruction, block verification, block bifurcation-prevention guaranteeing and other operations.

The invention discloses a multi-Agent transaction information protection method based on a block chain technology. According to the method, a transaction execution platform which only has credible andsafe transaction information protection execution environment is established by utilizing a block chain. A transaction process between the buyer and the seller is realized by using the transaction execution platform. Besides, a BFT-Raft consensus algorithm based on Byzantine fault tolerance is adopted, and the method has the advantages that due to the establishment of a multi-Agent e-commerce system, the transaction cost and the user time can be remarkably reduced, and illegal authorization acquisition, use and leakage of transaction information are effectively prevented. The BFT-Raft consensus algorithm ensures that the log is not tampered by applying a digital signature technology and incremental hash in a log replication link. Through a Committed proving mechanism, it is ensured that aselected Leader node must have all log items reaching consensus, the BFT-Raft consensus algorithm can solve the consensus problem in a Byzantine fault-tolerant environment, the number of nodes participating in verification and accounting is greatly reduced, and second-level consensus verification can be achieved.

The invention discloses a vehicular ad-hoc network data security sharing and storage system based on a blockchain technology. The vehicular ad-hoc network data security sharing and storage system based on the blockchain technology comprises a vehicle, a roadside unit, and a trusted institution. When data shared by the roadside unit, the vehicle performs digital signature on interactive informationby using a bilinear algorithm based on an elliptic curve to ensure the non-repudiation and integrity of the data; the roadside unit packs the collected data into a block, and uses the Byzantine fault-tolerant consensus mechanism to make the data block reach a coherent protocol across the network, thereby improving the fault tolerance of the system and making system more stable; after reaching theconsensus, the block is sorted by a smart contract in the roadside unit and stored in the blockchain, and other consensus nodes save the data synchronously; and the system rewards a corresponding number of data coins to the roadside unit, and then the data coins are assigned to the vehicle contributing the data by the smart contract, so as to keep the entire system active and stable.

The invention discloses a Byzantium fault tolerance method which comprises a node selection step, a proposal step, an endorsement step, a confirmation step and a block storage step, wherein in the node selection step, at least proposal nodes, endorsement nodes and confirmation nodes are selected from a blockchain network; in the proposal step, the proposal nodes construct new alternative blocks; in the endorsement step, the endorsement nodes carry out verification on the received alternative blocks, then carry out priority ranking on the alternative blocks and carry out endorsement on an alternative block with the highest priority; in the confirmation steps, if an alternative block is endorsed by a preset number of endorsement nodes in preset time, the confirmation nodes carry out confirmation on the alternative block; and in the block storage step, if an alternative block is confirmed by a preset number of confirmation nodes in preset time, the alternative block completes the consensus, and all the nodes in the blockchain network store the block which completes the consensus. The invention further discloses an implementation system of the Byzantium fault tolerance method. According to the invention, continuous operation in an extreme case can be ensured, and the Byzantium fault tolerance method and the implementation system thereof are beneficial for enlarging the scale of theblockchain network.

The present invention discloses a block chain contract-based fast transaction system. The system comprises a distributed authentication unit, a contract access server and contract nodes, wherein the distributed authentication unit comprises one or more service nodes and a plurality of authentication nodes, and the contract nodes comprise common contract nodes and rapid transaction contract nodes. The implementation method of the system includes the followings steps that: (1) a fast transaction is initialized; (2) a contract layer realizes the fast transaction; and (3) a bottom consensus layer realizes the distributed confirmation of rapid transaction history and writes confirmation results to a block chain. With the block chain contract-based fast transaction system of the invention adopted, rapid support for the transaction is realized, and the influence of the closing time of the block chain, the size of blocks and distributed network transmission on the execution of the transaction can be avoided; the Byzantine fault tolerance of the transaction system is maintained; delay phenomena of an existing block chain transaction mode in transaction spread, a consensus process and a contract execution process can be avoided; the details of the transaction can be hidden and encrypted; and the system has the inherent advantages of distributed block chains.

A serverless distributed file system manages the storage of files and directories using one or more directory groups. The directories may be managed using Byzantine-fault-tolerant groups, whereas files are managed without using Byzantine-fault-tolerant groups. Additionally, the file system may employ a hierarchical namespace to store files. Furthermore, the directory group may employ a plurality of locks to control access to objects (e.g., files and directories) in each directory.

The invention provides a private block chain block building method for a Byzantine fault tolerant algorithm of quartic communication. The method comprises: (1) all nodes carrying out hash mapping on the received transactions to obtain a bitarray sent to all remaining nodes, and each node carrying out 2 / 3 AND operation on the received bitarray to obtain a bitarray corresponding to a transaction intersection of over 2 / 3 nodes; (2) a block building node obtaining a transaction set according to the bitarray for building a block, and submitting the block to the remaining nodes; (3) a node receiving the block completing verification by comparing self bitarray with the transaction set in the block, and sending a digital signature of the verification result to all the remaining nodes after verification; and (4) forwarding all vote signatures received by all nodes on the block in second vote so that each node receives votes of all the nodes, and collecting statistics on the votes to obtain a final result, thus determining whether to accept the block.

The invention discloses a Byzantine fault tolerance method of a data block chain authorization participation consensus based on reward and punishment and a reward and punishment method thereof, relating to the technology of fault tolerance of a data block chain. A node reward and punishment algorithm is used to ensure that commands sent by nodes in a Byzantine fault tolerant data block chain which is authorized to participate in the consensus are honest. The technical points of the invention are that the method comprises the steps of (1) selecting consensus nodes in the data block chain, wherein the number of the consensus nodes is smaller than a node total number in the data block chain, (2) allowing the consensus nodes to carry out consensus games to reach a consensus on authenticity judgment of the commands sent by the nodes in the data block chain, and (3) carrying out reward and punishment on the nodes in the block chain based on a result that the consensus nodes reach the consensus.

The invention discloses an automatic recovery method for a blockchain consensus node. The method comprises the following steps that: 1) after crash, a reconnection node broadcasts an initial recovery message and obtains the check point information and the block height of other nodes; 2) the reconnection node receives the reply information of other nodes and counts the check point and the block height of a sender; 3) a target node is found, and the check point information, the block height and the block Hash of the target node are obtained; 4) the reconnection node carries out state transition and is recovered to the check point height of the target node; 5) the reconnection node asks for the message of PQC (Process Quality Control) from the target node; and 6) the reconnection node receives the PQC information returned from the target node, carries out normal consensus processing and repeatedly executes S5) and 6) until the height of the reconnection node block is recovered to normal node height. By use of the method, the problem that crash node reconnection is slow in a traditional PDFT (Practical Byzantine Fault Tolerance) consensus process is solved, and a quick reconnection method for the crash reconnection node on the blockchain is put forward.

The invention relates to a block chain update method and a block chain update system. The method comprises the steps as follows: a central node receives a request message sent by a client; the centralnode broadcasts the request message to each node in a first node group where the central node is located, and each node in the first node group performs consensus processing on the request message; when each node in the first node group reaches a consensus for the request message, each node in a second node group and the node in the first node group perform data synchronization on the request message; when each node in the second node group completes data synchronization on the request message, a block chain is updated according to the request message. According to the block chain update method and the block chain update system provided by the invention, all nodes of the block chain are divided into two parts, the problems that there are excessive nodes and Byzantium fault-tolerance is not applicable are avoided, the quantity of all nodes can be accommodated by the network is improved, and the network fault-tolerant capability and expansibility are enhanced.

A method for byzantine fault-tolerant replication of data on a plurality of n servers includes performing, by a primary node (PN), a prepare procedure that includes computing a prepare message including a unique identifier and multicasting the prepare message to the REPN. The method further includes performing, by the PN, a commit procedure that includes receiving, from each of a portion of the REPN, a prepare message reply signature part and aggregating each of the prepare message reply signature parts to generate a prepare message reply aggregated signature, checking the validity of the prepare message reply aggregated signature, and upon determining that the prepare message reply aggregated signature is valid, computing a commit message including the prepare message reply aggregated signature and multicasting the commit message to the REPN. The method further includes transmitting, to the client, the commit message reply aggregated signature.

The invention relates to a verification based blockchain common recognition method. A client sends a request message to a verification initiation node; the verification initiation node organizes a pre-preparation message and broadcasts the message to other verification nodes in the network; the other verification nodes organize signature messages and return the signature messages to the verification initiation node respectively; the verification initiation node counts the signature messages which are received correctly, submission of the present node is executed when the number of the signature messages which are received correctly reaches a given threshold, and a verification message is organized and sent to the other verification nodes; each of the other verification nodes checks digitalsignatures in the message successively, when the number of the digital signature that passing checking reaches a given threshold, submission operation of the present node is executed, and a verification reply message is organized and returned to the verification initiation node; and the verification initiation nodes organizes a response message and back feeds the response message to the client. Compared with a practical Byzantine fault tolerant method, the network communication frequency and communication data bulk are reduced, and the common recognition efficiency is improved.

The invention provides a consensus method, device and system based on effective computational force contribution. The method includes the steps of receiving computational tasks issued by a computational publisher and computational requirements corresponding to the computational tasks; configuring computing tasks according to computing requirements; obtaining the data needed by the computing task and compiling the computing task into a Boolean circuit; forming a plurality of parallel computing tasks, and distributing the parallel computing tasks to a plurality of computing nodes for computing;receiving the calculation result and the calculation proof of the parallel calculation task by the calculation node, and determining whether the calculation result is valid or not according to the calculation proof; if it is valid, determining the cumulative calculation contribution value of the calculation node corresponding to the calculation result, and allocating the preset reward for each calculation node; receiving voting data of each computing node as cumulative calculated contribution value, and voting on the candidate nodes; obtaining the N consensus nodes, wherein the practical Byzantine fault-tolerant algorithm is used to complete the consensus of the block data among the N consensus nodes.

The invention discloses a Byzantine fault-tolerant blockchain generation method based on a rumor propagation protocol, and the method comprises the steps that a consensus network selects a speaker node; a speaker node broadcasts a proposal; a member node verifies the proposal; nodes calculates the local data, a global data vector and consensus data therebetween; the node verifies transaction consensus data is between the nodes; the nodes generate blocks and adds the blocks to the blockchain, and finally output a new complete blockchain. The invention introduces the rumor propagation protocol,and the method enables the system to tolerate nearly half of Byzantine nodes (wrong nodes), and improves fault tolerance. Because the data structure adopted by the system is consistent, the scalability of the system is improved, and the correct nodes can identify the Byzantine nodes in the blockchain system more easily. In addition, in the method of the present invention, the speaker node will betransferred due to the change of the blockchain length, and the nodes in the system are all in the same position, thereby avoiding the single point fault problem, and enabling the system to have better balanced dynamic load performances.

An anti-adaptive attack alliance chain consensus method based on Byzantine fault tolerance comprises the following steps: constructing an anonymous sorting master selection algorithm based on ring signatures, and selecting a potential proposor PP from all consensus nodes in an alliance chain network in a concealed manner; enabling a potential proposor PP to construct a proposal block, sign the proposal block and broadcast the proposal block to the alliance chain network; enabling the consensus node to verify the received proposal block, vote the proposal block passing the verification based on a threshold signature, and broadcast a voting result in the alliance chain network; if a consensus node receives a legal threshold signature of the proposal block within a predetermined time, enabling the proposal block to complete the consensus; and enabling all nodes in the alliance chain network to store the blocks completing the consensus. The method has the advantages that the system overhead is reduced, the expandability is improved, the safety is higher, the system activity can be effectively ensured before and after proposal, and the support is provided for a high-availability Byzantine system.

The invention discloses a practical Byzantine fault-tolerant blockchain consensus method and system based on multiple leader nodes, and the method comprises the steps: enabling consensus nodes to be connected to a kafka cluster, and uploading the transaction received by the consensus nodes and the corresponding consensus node information to the kafka cluster; performing the same segmentation of the corresponding consensus nodes, and packaging the corresponding transactions into a block; performing the single matching grouping of non-leader nodes according to the number of leader nodes, and enabling each group to comprise one leader node, executing PBFT in each group, thereby achieving the synchronization with a block corresponding to the leader node. Compared with the prior art, the methodsolves a problem of low practicality caused by a condition that there are many nods in a network because a PBFT algorithm is too complex, shortens the time of a blockchain system in generating and confirming one block, greatly improves the throughput capacity of the whole blockchain system, and is higher in practicality.

The invention discloses a warehouse receipt pledge financing management system and method based on a block chain in the supply chain industry. A protocol layer, a data layer, a function layer and a service layer which are fully covered by a warehouse receipt pledge financing service system based on a block chain are designed. A practical Byzantine fault-tolerant node consensus mechanism, a data distributed evidence storage feature, an information transparency feature, a distributed operation and maintenance feature and the like adopted by a protocol layer based on a block chain are more convenient for big data structured analysis and processing, relatively accurate enterprise portraits are realized, and real-time data synchronization and data security are realized. Therefore, unified business decision optimization arrangement and risk control are facilitated, and convenience is provided for penetration type supervision. The system and the method can completely cover the links of warehouse receipt pledge article value dynamic evaluation, pledge release, credit extension and examination, financing subject credit risk control, penetration type supervision and the like, and avoid the problems of repeated warehouse receipt pledge, serious false warehouse receipt pledge phenomenon and low credit extension safety evaluation quality of financial institutions.

The invention provides a Byzantine fault-tolerant consensus method and a terminal applied to a coalition chain. The method comprises the steps of in each round of consensus process, according to the private key, serial number, current view and the hash value corresponding to the block generated in the previous round of consensus process, calculating the hash value corresponding to each selected consensus node, thereby the unique first consensus node is selected; And generating proposal information through the first consensus node and sending the proposal information to each consensus node to be selected respectively; according to the verification passing information corresponding to the proposal information sent by the selected consensus node, generating the identification information andtransmitting the identification information to each selected consensus node respectively; and if the number of verification passing information corresponding to the identification information receivedby the first consensus node exceeds the preset number, executing the next round of consensus. By adopting the scheme, the invention not only improves the consensus performance of the alliance chain,but also ensures the safety of the alliance chain.

Disclosed herein are an apparatus and method for achieving distributed consensus based on decentralized Byzantine fault tolerance. The apparatus may include one or more processors and an execution memory for storing at least one program that is executed by the one or more processors, wherein the program is configured to receive delegate request messages, each including a first transaction for requesting distributed consensus proposed by a client, and determine congress candidate nodes forming a consensus quorum, to be consensus nodes based on the delegate request messages, generate a prepare message that includes a second transaction for obtaining consent to results of determination of the consensus nodes, and send the prepare message to the consensus nodes, and receive commit messages, each including an electronic signature of a corresponding consensus node, from the respective consensus nodes, and broadcast a reply message indicative of results of verification of the electronic signatures.

The invention discloses a Byzantine fault tolerance method, which comprises three sub-protocols including a consensus protocol, a view replacement protocol and a check point protocol, the consensus protocol coordinates the execution sequence of the request from the replica node to the main replica node to be consistent; when the replica nodes cannot be consistent, the slave replica nodes trigger the view replacement protocol, select new master replica nodes and execute the consensus protocol again; after the distributed system executes a certain number of requests each time, logs of the replica nodes are periodically cleared, and the replica nodes update the states of the replica nodes. According to the method, good performance can be obtained in the absence of error nodes, smooth performance reduction can be realized in the presence of the error nodes, the problem of inconsistent node states possibly occurring in the continuous view replacement process is solved, and the problem of severe performance reduction in the presence of the error nodes in some BFT protocols is solved.