CN107392608B

CN107392608B - Block chain system-based digital asset transaction method and block chain system

Info

Publication number: CN107392608B
Application number: CN201710561462.4A
Authority: CN
Inventors: 张健; 张博; 赵海涛
Original assignee: Beijing Bochen Technology Co ltd
Current assignee: Beijing Bochen Technology Co ltd
Priority date: 2017-07-11
Filing date: 2017-07-11
Publication date: 2020-07-07
Anticipated expiration: 2037-07-11
Also published as: CN107392608A

Abstract

The invention discloses a digital asset transaction method based on a blockchain system and the blockchain system. The block chain system is a tree-shaped distributed block chain system comprising a plurality of levels of block chains, and the method comprises the following steps: the first block chain receives a digital asset transaction request from a client and determines a digital asset corresponding to the digital asset transaction request; judging whether a home block chain corresponding to the digital asset is a first block chain; if yes, the first blockchain processes the digital asset transaction request; if not, the first block chain refuses the digital asset transaction request; wherein, the attribution block chain corresponding to the digital assets is the block chain generating the digital assets. This approach is particularly useful for transactions that use a digital asset at a time, which can only be used once; in addition, the method can also realize cross-chain transaction among the digital assets, and the digital assets before and after the cross-chain transaction is executed respectively correspond to different attribution block chains, so that the safety of the assets is improved.

Description

Block chain system-based digital asset transaction method and block chain system

Technical Field

The invention relates to the technical field of information, in particular to a digital asset transaction method based on a blockchain system and the blockchain system.

Background

The blockchain technology is a brand new distributed infrastructure and computing paradigm that utilizes blockchain data structures to verify and store data, utilizes distributed node consensus algorithms to generate and update data, cryptographically secures data transmission and access, and utilizes intelligent contracts composed of automated script code to program and manipulate data. The blockchain technique itself has many advantages: on one hand, as the blockchain network can realize self-restraint through an algorithm, the behavior of any malicious fraud system can be rejected and restrained by other nodes in the network, and therefore, the blockchain system can realize safe network transaction without depending on central authority support and credit endorsement. On the other hand, as the block chain adopts the one-way hash algorithm, and each newly generated block is strictly advanced according to the time linear sequence, the irreversibility of time causes any behavior of trying to invade and tamper the data information in the block chain to be easily traced, and causes the data information to be rejected by other nodes, thereby limiting the related illegal behavior. Therefore, the blockchain technology is increasingly widely applied to various fields such as finance, banking and the like.

However, most of the conventional blockchain systems are implemented by decentralized distributed architecture, each network transaction needs to be validated through the consensus operation of all blockchain nodes in the system, and the transaction needs to be recorded on the large system account maintained by all blockchain nodes. However, the inventor finds that the prior art has at least the following problems in the process of implementing the invention: when the blockchain system is used for realizing the transaction of the digital assets, the transaction process of each digital asset needs to be completed by all nodes in the blockchain system together, so that the efficiency is low, multiple transactions cannot be executed concurrently, and the risk that the digital assets are attacked by malicious nodes is increased.

Disclosure of Invention

In view of the above, the present invention has been made to provide a digital asset transaction method based on a blockchain system and a blockchain system that overcome or at least partially solve the above problems.

According to an aspect of the present invention, there is provided a digital asset transaction method based on a blockchain system, wherein the blockchain system is a tree-shaped distributed blockchain system including a plurality of hierarchical levels of blockchains, the method including: the first block chain receives a digital asset transaction request from a client and determines a digital asset corresponding to the digital asset transaction request; judging whether a home block chain corresponding to the digital asset is the first block chain; if so, the first blockchain processes the digital asset transaction request; if not, the first blockchain rejects the digital asset transaction request; wherein, the attribution block chain corresponding to the digital assets is the block chain generating the digital assets.

According to another aspect of the present invention, there is provided a blockchain system for implementing a digital asset transaction, wherein the blockchain system is a tree-shaped distributed blockchain system including a plurality of hierarchical levels of blockchains, and the blockchain system at least includes: a first blockchain adapted to receive a digital asset transaction request from a client, determine a digital asset corresponding to the digital asset transaction request; judging whether a home block chain corresponding to the digital asset is the first block chain; if so, the first blockchain processes the digital asset transaction request; if not, the first blockchain rejects the digital asset transaction request; wherein, the attribution block chain corresponding to the digital assets is the block chain generating the digital assets.

In summary, in the digital asset transaction method and system based on the blockchain system provided by the present invention, since the blockchain system is a tree-shaped distributed blockchain system including a plurality of levels of blockchains, each blockchain in the system can independently process transactions related to the blockchain by dividing the levels. And the block chain of the generated digital assets is used as the home block chain of the digital assets, so that each digital asset only corresponds to a unique home block chain and related transaction operation can be carried out only through the home block chain, thereby not only being beneficial to realizing concurrence of multiple digital asset transactions and improving transaction efficiency, but also obviously improving the safety of the digital assets and avoiding the risk of the digital assets being attacked by irrelevant malicious block chains.

The foregoing description is only an overview of the technical solutions of the present invention, and the embodiments of the present invention are described below in order to make the technical means of the present invention more clearly understood and to make the above and other objects, features, and advantages of the present invention more clearly understandable.

Drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the invention. Also, like reference numerals are used to refer to like parts throughout the drawings. In the drawings:

FIG. 1 shows an overall architecture diagram of a blockchain system;

FIG. 2 is a flow chart showing a digital asset transaction method provided in the second embodiment;

FIG. 3a shows a schematic flow chart of a first implementation of step S230;

FIG. 3b shows a schematic flow chart of a second implementation of step S230;

fig. 4 shows a schematic diagram of the consensus operation.

Detailed Description

Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

Example one

The embodiment of the invention provides a digital asset transaction method based on a blockchain system, wherein the blockchain system is a tree-shaped distributed blockchain system comprising a plurality of levels of blockchains, and the method comprises the following steps: the first block chain receives a digital asset transaction request from a client and determines a digital asset corresponding to the digital asset transaction request; judging whether a home block chain corresponding to the digital asset is the first block chain; if so, the first blockchain processes the digital asset transaction request; if not, the first blockchain rejects the digital asset transaction request; wherein, the attribution block chain corresponding to the digital assets is the block chain generating the digital assets.

The tree-shaped distributed blockchain system includes a plurality of levels of blockchains, and the specific number of levels and the number of blockchains included in each level can be flexibly set by those skilled in the art. In addition, the first blockchain may be a blockchain at any level. The types of digital asset transaction requests may include a variety of: such as a request for a type of asset consumption, a request for a type of asset transfer, etc.

Since the blockchain system is a tree-shaped distributed blockchain system comprising a plurality of levels of blockchains, each blockchain in the system can independently process the transaction related to the blockchain by means of hierarchy division. And the block chain of the generated digital assets is used as the home block chain of the digital assets, so that each digital asset only corresponds to a unique home block chain and related transaction operation can be carried out only through the home block chain, thereby not only being beneficial to realizing concurrence of multiple digital asset transactions and improving transaction efficiency, but also obviously improving the safety of the digital assets and avoiding the risk of the digital assets being attacked by irrelevant malicious block chains.

Example two

The embodiment of the invention provides a specific digital asset transaction method based on a blockchain system. For ease of understanding, the block chain system according to the second embodiment of the present invention is first described below:

the block chain system is divided into a plurality of levels from top to bottom, and specifically comprises: a top level block chain at a top level of the plurality of levels, a middle level block chain at a middle level of the plurality of levels, and a bottom level block chain at a bottom level of the plurality of levels. The number of the top level and the bottom level is 1, the number of the middle level is N, and N is an integer greater than or equal to 0. For example, when N is equal to 1, as shown in fig. 1, the blockchain system includes three levels: top level blockchain 0 at the top level, middle level blockchains 00, 01, 02 at one level at the middle level, and a plurality of bottom level blockchains 000, 001.. 022 at the bottom level. Wherein, each middle layer block chain 00, 01, 02 is directly connected with the top layer block chain 0 and belongs to the top layer block chain 0, that is: the top-level block chain 0 is a parent node (also called an upper-level block chain) of each of the middle-level block chains 00, 01, 02, and each of the middle-level block chains 00, 01, 02 is a child node (also called a lower-level block chain) of the top-level block chain 0. Each bottom layer block chain is directly connected with one middle layer block chain and belongs to the middle layer block chain. Namely: the middle block chain serves as a parent node (also called an upper block chain) of the bottom block chain directly connected thereto, and each bottom block chain serves as a child node (also called a lower block chain) of the middle block chain directly connected thereto. Specifically, the bottom layer block chains 000, 001, 002 are connected to the middle layer block chain 00, the bottom layer block chains 010, 011 are connected to the middle layer block chain 01, and the bottom layer block chains 020, 021, 022 are connected to the middle layer block chain 02. It follows that each blockchain has a corresponding upper blockchain and/or lower blockchain; the number of the upper layer blockchains corresponding to each blockchain is one (of course, in some special cases, the number of the upper layer blockchains corresponding to each blockchain may also be multiple), and the number of the lower layer blockchains corresponding to each blockchain is one or more. For example, the first hierarchical blockchain 0 has three lower-level blockchains (i.e., the second hierarchical blockchains 00, 01, and 02), and the third hierarchical blockchain 000 has one upper-level blockchain (i.e., the second hierarchical blockchain 00). Wherein the horizontal and vertical position of a blockchain in the whole blockchain system can be quickly determined by the chain ID (also called identification) of each blockchain. The blockchain in this embodiment substantially refers to a blockchain node (or called a blockchain network node), or the blockchain in this embodiment may also be a blockchain cluster.

In the blockchain system shown in fig. 1, on one hand, the blockchain is divided laterally, and the lateral division refers to: the same level may include a plurality of same level blockchains, and the same level blockchains are siblings with each other. All transactions are divided into intra-chain transactions and cross-chain transactions among the block chains of multiple levels through the transverse chain division, so that the transactions of all different block chains can be parallel, and the performance of the whole block chain system is greatly improved. On the other hand, the block chain is vertically layered, and the vertical layering refers to: and dividing all block chains into a plurality of different levels from top to bottom. The blockchain can be divided into a plurality of groups of blockchains of different levels by longitudinally layering the blockchain, the blockchain of the lower layer submits the aggregated transaction to the upper layer, and meanwhile, the transactions between the accounts of the upper layer and the accounts of the lower layer are realized. Therefore, the flexibility of the blockchain system can be improved through the transverse branch chain and the longitudinal branch chain, and guarantee is provided for concurrent execution of multiple transactions.

In addition, each blockchain network node in the blockchain system shown in fig. 1 is capable of independently performing consensus operations and accounting operations. Specifically, each blockchain is used for performing consensus on the transactions related to the blockchain network node, and records the successful transactions of the consensus in the ledger of the blockchain. Wherein the transactions associated with the blockchain network node include at least one of: intra-chain transactions that occur within the blockchain network node, and inter-chain transactions that occur between the blockchain network node and other blockchain network nodes; wherein the cross-chain transaction further comprises: the same level cross-chain transaction and the cross-level cross-chain transaction. Therefore, different from the way of providing only one unified consensus operation entry in the traditional blockchain system (the consensus operation of all transactions in the traditional blockchain system must be realized through the unified consensus operation entry, so that multiple transactions cannot be executed concurrently), the way in the present invention is equivalent to providing multiple consensus operation entries that can be used concurrently (each blockchain network node has an entry that can independently complete the consensus operation), and each blockchain network node only performs consensus on the network transaction related thereto, and other blockchain network nodes unrelated to the transaction do not participate in the consensus operation of the transaction, so that the consensus operation of multiple transactions can be performed concurrently, which not only improves the concurrency of the system, but also reduces the delay of the consensus operation. And different from the mode of only providing one large account book in the traditional block chain system (the traditional block chain system records all transactions among all block chain network nodes through one large account book), the mode of the invention is equivalent to providing a plurality of independent small account books (each block chain network node is provided with an account book sub-node capable of independently completing accounting operation), and the account book in each block chain network node only needs to record the transaction account book related to the block chain network node and does not need to record the transaction account book unrelated to the block chain network node, thereby improving the efficiency of accounting and inquiring. It can be seen that the blockchain system shown in fig. 1 is essentially billed through the tree-shaped distributed ledger. The tree-shaped distributed account book is as follows: the account book is of a tree structure and consists of a plurality of sub account books according to a tree shape, and different sub account books have a hierarchical relationship (each block chain has a corresponding sub account book).

In addition, in order to facilitate the communication among the plurality of blockchain network nodes between the layers, at least one message network unit may be further disposed in the blockchain system in this embodiment. Each message network node is connected with the blockchain network node of each hierarchy respectively and is used for forwarding various messages related to the transaction, such as consensus result messages among the blockchain network nodes of each hierarchy.

Based on the blockchain system shown in fig. 1, fig. 2 shows a flow chart of the digital asset transaction method provided in the second embodiment. As shown in fig. 2, the method comprises the steps of:

step S210: the first block chain receives a digital asset generation request from a client, allocates a corresponding asset identification for a digital asset corresponding to the digital asset generation request, and generates and stores block chain signature information generated for the asset identification of the digital asset.

The first blockchain may be a blockchain at any level in the blockchain system, and the present invention does not limit the chain ID of the first blockchain. In addition, the digital assets can be generated on any block chain, and the digital assets generated on the first block chain are only described as an example in the embodiment. Specifically, the digital assets may be embodied in the form of account ID + account balance, or may be represented by digital assets marked with their ownership, and the latter form of digital assets is mainly described in the present embodiment. Also, if the digital assets are allowed to be used only once, they can be referred to as digital assets (also called virtual assets) used once, and the digital assets mentioned below in this embodiment are all digital assets used once. Wherein, one-at-a-time digital assets can be realized by UTXO (un Transaction Output) in bitcoin Transaction, containing value and script using the value. Where value represents the value of the asset and the script is used to limit the conditions of use of the asset. Of course, the one-at-a-time digital asset in the present embodiment is not limited to the UTXO format, but may take other forms.

The basic digital asset comprises two parts of asset description information and asset use condition script. Wherein the asset description information comprises at least one of: asset characteristics (e.g., movie tickets, coupons, shopping cards, etc.), asset value (otherwise known as denomination), asset identification (e.g., ID), etc. The identification and specific attributes of the asset can be known through the asset description information. The asset use condition script is used for setting the use condition of the asset and allowing the client to access the asset only when the client can provide information according with the use condition. For example, the use condition may be represented by a hash value of a character string and/or a number. The property can be prevented from being maliciously operated by an illegal user through the property use condition script. In addition, in order to improve performance, the digital asset may further include block chain signature information and an asset key in addition to the asset description information and the asset usage condition script. The block chain signature information is signed by the home block chain corresponding to the asset, and is mainly used for identifying the validity of the asset on the home block chain and proving that the asset is billed by the home block chain. The asset key is also called an account public key and is indicated by an asset owner, and when the asset contains the part, only a client and/or a block chain which holds the corresponding private key can operate the asset.

In this step, after receiving a digital asset generation request from the client, the first block link allocates a corresponding asset identifier to the digital asset corresponding to the digital asset generation request, and generates and stores block chain signature information generated for the asset identifier of the digital asset. In this embodiment, a blockchain of a digital asset is generated as a home blockchain of the digital asset, and in the home blockchain, blockchain signature information generated for an asset identifier of the digital asset is stored. Each digital asset can only perform related operations by its corresponding home blockchain, thereby increasing the security of the digital asset.

Step S220: the first block chain receives a digital asset transaction request from a client, determines a digital asset corresponding to the digital asset transaction request, and judges whether a home block chain corresponding to the digital asset is a first block chain; if yes, go to step S230; if not, go to step S240.

First, after receiving a digital asset transaction request from a client, a first block link determines a digital asset corresponding to the digital asset transaction request according to an asset identifier contained therein. Then, whether the first block chain stores the block chain signature information generated for the asset identifier of the digital asset is judged, if yes, the attribution block chain corresponding to the digital asset is determined to be the first block chain, and step S230 is executed; if not, determining that the home blockchain corresponding to the digital asset is not the first blockchain, and executing step S240. In step S240, the first blockchain rejects the digital asset transaction request to prevent malicious operations on the digital asset by unrelated blockchains. Therefore, one digital asset can only correspond to one attribution block chain through the attribution block chain concept and can only be operated by the attribution block chain, so that the method is beneficial to improving the safety of the asset and realizing the concurrent execution of a plurality of asset transactions.

Step S230: the first blockchain processes the digital asset transaction request.

The specific processing manner depends on the type of the digital asset transaction request, which includes various types, for example, an asset transfer type request, an asset consumption type request, and the like. In the case of an asset transfer class request, since the digital assets in this embodiment are used once, the transaction transfer process is actually to destroy the old assets and issue new assets, and the new assets are changed to corresponding new owners. If the request is an asset consumption request, the corresponding state of the asset can be changed after the asset is directly consumed.

As can be seen, in the specific processing procedure of step S230, two judgment logics may be included: the first re-judgment logic is used for judging the type of the digital asset transaction request (comprising an asset transfer class, an asset consumption class, a new asset class and the like), and then executing the operation corresponding to the type according to the judged type of the digital asset transaction request. The second judging logic is used for judging whether the digital asset transaction request belongs to intra-chain transaction or cross-chain transaction, and executing a corresponding intra-chain transaction flow or cross-chain transaction flow according to a judgment result. Specifically, whether the block chains corresponding to the asset transfer-in party and the asset transfer-out party in the digital asset transaction request are the same block chain is judged to determine that the transaction belongs to intra-chain transaction or cross-chain transaction: if the block chains corresponding to the asset transfer-in party and the asset transfer-out party included in the digital asset transaction request are the same block chain (for example, both are the first block chain), determining that the transaction is an intra-chain transaction, and correspondingly, executing a processing procedure corresponding to the intra-chain transaction (specifically, refer to fig. 3 a); if the blockchains corresponding to the asset transfer-in party and the asset transfer-out party included in the digital asset transaction request belong to different blockchains respectively (for example, the asset transfer-out party belongs to the first blockchain and the asset transfer-in party belongs to the second blockchain), it is determined that the transaction is a cross-chain transaction, and accordingly, a processing procedure corresponding to the cross-chain transaction is executed (specifically, refer to fig. 3 b). In addition, the execution sequence of the above-mentioned dual determination logic is not limited in the present invention, and the type of the transaction may be determined first, or the transaction may be determined as an intra-chain or inter-chain transaction first. In addition, the first re-determination logic may also be omitted when the transaction type is limited to the asset transfer class only. In conclusion, various modifications and variations can be made to the specific implementation details of step S230 by those skilled in the art.

In this embodiment, a resource transfer type request is taken as an example for explanation, and accordingly, the digital asset transaction request received by the first block link is specifically an asset transfer request. Specifically, step S230 may be further divided into two implementation manners according to the location of the block chain corresponding to the asset transfer-in party included in the asset transfer class request. Fig. 3a shows a schematic flow chart of a first implementation manner of step S230, in the manner shown in fig. 3a, the blockchain corresponding to the asset transferring party is the first blockchain, that is: the asset roll-out party and the asset roll-in party belong to the same block chain, and therefore, the corresponding transaction is an intra-chain transaction. Fig. 3b shows a flowchart of a second implementation manner of step S230, in the manner shown in fig. 3b, the blockchain corresponding to the asset transferring party is not the first blockchain, that is: the asset transferor and the asset transferor belong to different blockchains, and therefore, the corresponding transaction is a cross-chain transaction.

As shown in fig. 3a, when the digital asset transaction request received by the first blockchain is an asset transfer request and the blockchain corresponding to the asset transfer party is the first blockchain, the step S230 specifically includes the following sub-steps:

step S231: determining that the block chain corresponding to the asset transfer party contained in the asset transfer request is a first block chain, namely: it is determined that the asset transfer request belongs to an in-chain transaction.

Specifically, the asset transfer request includes not only information corresponding to the asset transfer party, but also a chain ID of an original asset holder corresponding to the asset transfer party and a block chain corresponding to the original asset holder; and the system also comprises information corresponding to the asset transfer party, and specifically comprises a new asset holder corresponding to the asset transfer party and a chain ID of a block chain corresponding to the new asset holder. According to the information, whether the block chain corresponding to the asset transfer party contained in the asset transfer request is the first block chain can be determined, the mode shown in fig. 3a only describes a scenario that the block chain corresponding to the asset transfer party contained in the asset transfer request is the first block chain, and if the block chain corresponding to the asset transfer party contained in the asset transfer request is determined not to be the first block chain according to the information, the processing is performed through the mode shown in fig. 3 b.

In order to improve the security of the transaction and to prevent the occurrence of the malfunction, it may be further determined whether the user corresponding to the client that transmitted the digital asset transaction request is the rightful holder of the digital asset in step S231, and only if the determination result is yes, the subsequent steps may be performed. The determination operation may be executed in step S220, and the specific execution timing of the determination operation is not limited by the present invention. And during the judgment, the information of the asset transfer party contained in the asset transfer request can be acquired, and if the information of the asset transfer party contained in the asset transfer request is matched with the related information recorded in the digital asset, the user corresponding to the client is determined to be a legal holder. In addition, the determination may be performed by combining information such as asset characteristics, asset value, asset identification, asset use condition scenario, and/or asset key included in the digital asset. For example, a transaction may be constructed by the owner of the asset to be traded and signed or a proof of asset use submitted, after which the transaction is submitted to the home block chain of the digital asset, which determines the legitimacy of the transaction by verifying whether the asset's signature or conditions of use are correct.

Step S232: each node in the first blockchain agrees on the first transaction information corresponding to the asset transfer request.

Wherein the first transaction information at least comprises: asset holder information prior to asset transfer for providing to the first blockchain to destroy digital assets corresponding to the digital asset transaction request in the first blockchain; and the asset holder information after the asset transfer is used for being provided for the first block chain, so that digital assets equivalent to the destroyed digital assets are generated in the first block chain, and asset identification and new asset holder information corresponding to the generated digital assets equivalent to the destroyed digital assets are set. Specifically, in a real transaction, the first transaction information may include: the asset paid (generated by the client submitting the transaction to identify the digital asset to be transferred), a payment account signature (generated by the client user submitting the transaction to verify whether the user is the legitimate holder of the asset), a collection account (specified by the client submitting the transaction to determine the holder of the asset after the transfer of the asset), and a transaction ID (assigned by the first blockchain to uniquely identify the transaction for processing in subsequent steps).

For example, assume that the asset holder prior to the asset transfer is user a, which corresponds to the first client; the asset holder after the asset transfer is user B, which corresponds to the second client. And, both the first client and the second client belong to the bottom-level block chain 000 in fig. 1 (i.e., the first block chain is the bottom-level block chain 000). Accordingly, after the user a submits the above-mentioned asset transfer request and the first blockchain verifies that the user a has the asset legally and the asset is not used, the old digital asset held by the user a is destroyed in the bottom blockchain 000, wherein the asset identifier corresponding to the old digital asset is, for example, 000X. Then, a new digital asset is issued in the bottom floor block chain 000, the asset identification corresponding to the new digital asset can be determined to be 000YY through a preset algorithm, the new digital asset is equal to the old digital asset in value, and the user B is the holder of the new digital asset. Therefore, as the home block chains corresponding to the new and old digital assets are all the first block chains, the prefixes of the asset identifications are all the chain IDs 000 of the first block chains. Accordingly, user a confirms that the old digital asset has been destroyed, and user B confirms that the new digital asset is received.

In addition, since the first blockchain usually includes a plurality of network nodes, the network nodes in the first blockchain need to participate in the consensus and accounting process of the transaction together. Wherein the specific process of the consensus operation can be flexibly set by the skilled person. The core of the scheme is as follows: each block chain can independently complete the consensus and accounting operation of all transactions in the block chain without other block chains participating in the consensus and accounting, so that the operation efficiency is improved, and the concurrent execution of multiple transactions on different block chains is facilitated.

Step S233: if the consensus is successful, the first transaction information is billed in the first blockchain.

Specifically, each node in the first blockchain records first transaction information corresponding to the transaction in an account book of the first blockchain. Therefore, the transaction is only recorded in the ledger of the first block chain, and is not recorded in the ledger of other block chains, so that the scale of the ledger can be simplified, and the inquiry is facilitated. The transfer operation of the digital assets in the same block chain is realized through the mode.

As shown in fig. 3b, when the digital asset transaction request received by the first block link is an asset transfer request and the block chain corresponding to the asset transfer party is the second block chain, the step S230 specifically includes the following steps:

step S231': determining that the block chain corresponding to the asset transfer party contained in the asset transfer request is a second block chain, namely: the asset transfer request is determined to belong to a cross-chain transaction.

Specifically, the asset transfer request includes not only information corresponding to the asset transfer party, but also a chain ID of an original asset holder corresponding to the asset transfer party and a block chain corresponding to the original asset holder; and the system also comprises information corresponding to the asset transfer party, and specifically comprises a new asset holder corresponding to the asset transfer party and a chain ID of a block chain corresponding to the new asset holder. And determining whether the block chain corresponding to the asset transfer party contained in the asset transfer request is the first block chain or not according to the information. In the flow shown in fig. 3b, the blockchain corresponding to the asset transfer party is the second blockchain. The second blockchain may be any blockchain in the blockchain system different from the first blockchain, and the present invention does not limit the chain ID of the second blockchain.

In order to improve the security of the transaction and to prevent the occurrence of an erroneous operation, it may be further determined whether the user corresponding to the client that transmitted the digital asset transaction request is the rightful holder of the digital asset in step S231', and only if the determination result is yes, the subsequent steps may be executed. The determination operation may be executed in step S220, and the specific execution timing of the determination operation is not limited by the present invention. And during the judgment, the information of the asset transfer party contained in the asset transfer request can be acquired, and if the information of the asset transfer party contained in the asset transfer request is matched with the related information recorded in the digital asset, the user corresponding to the client is determined to be a legal holder. In addition, the determination may be performed by combining information such as asset characteristics, asset value, asset identification, asset use condition scenario, and/or asset key included in the digital asset. For example, a transaction may be constructed by the owner of the asset to be traded and signed or a proof of asset use submitted, after which the transaction is submitted to the home block chain of the digital asset, which determines the legitimacy of the transaction by verifying whether the asset's signature or conditions of use are correct.

Step S232': and the first block chain sends the second transaction information corresponding to the asset transfer request to the second block chain.

Specifically, in this embodiment, the master node included in the first blockchain may send the second transaction information to the second blockchain, and the master node in the first blockchain may be determined by an election method or other methods. In a specific implementation, the information may be sent only to the master node in the second blockchain, or may be sent to each node in the second blockchain at the same time.

Wherein the second transaction information at least comprises: asset holder information prior to asset transfer for providing to the first blockchain to destroy digital assets corresponding to the digital asset transaction request in the first blockchain; and the asset holder information after the asset transfer is used for being provided for the second block chain, so that digital assets equivalent to the destroyed digital assets are generated in the second block chain, and asset identification and new asset holder information corresponding to the generated digital assets equivalent to the destroyed digital assets are set. In addition, after the generated asset identification and the asset holder information corresponding to the destroyed digital asset are set, the second blockchain further generates and stores blockchain signature information generated for the generated asset identification of the destroyed digital asset.

The specific content of the second transaction information is similar to that of the first transaction information, and the difference is only that: the block chain where the asset holder after the asset transfer corresponding to the second transaction information is located is different from the first block chain where the asset holder before the asset transfer is located, that is: the asset transfer transaction is a cross-chain transaction. Accordingly, the asset transfer transaction needs to be completed in two chains of the tree-shaped distributed account, requiring the input digital assets to be assigned to one chain and the output digital assets to be assigned to the other chain, and therefore, in order to ensure that the destruction of the input digital assets is consistent with the creation of the output digital assets, the two chains need to be identified and then synchronously accounted on the two chains.

Step S233': the first blockchain and the second blockchain commonly share common knowledge about the second transaction information.

Since the second transaction information involves two blockchains, there is a need for both blockchains to be commonly identified and billed. For example, assume that the asset holder prior to the asset transfer is user a, which corresponds to the first client; the asset holder after the asset transfer is user C, which corresponds to the third client. And, the first client is subordinate to the bottom layer block chain 000 in fig. 1 (i.e., the first block chain is the bottom layer block chain 000), and the third client is subordinate to the bottom layer block chain 002 in fig. 1 (i.e., the second block chain is the bottom layer block chain 002). Correspondingly, after the user a submits the asset transfer request to the first blockchain, and the first blockchain verifies that the user a has the asset legally and the asset is not used, the second transaction information corresponding to the request needs to be sent to the second blockchain for common processing: in one aspect, the first blockchain destroys old digital assets held by user a in blockchain 000, wherein the asset identifier corresponding to the old digital assets is, for example, 000S. On the other hand, the second blockchain issues a new digital asset in blockchain 002, the asset id corresponding to the new digital asset can be determined to be 002ZZ through a preset algorithm, and the new digital asset is equal to the old digital asset in value, and user C is the holder of the new digital asset. It can be seen that, because the home block chains corresponding to the new and old digital assets are different, the prefixes of the asset identifications are also different: the asset identification prefix of the old asset is 000, which indicates that the home block chain of the asset is 000; the new asset has an asset identification prefix of 002, indicating that the home block chain for that asset is 002. Accordingly, user a confirms that the old digital asset has been destroyed, and user C confirms that the new digital asset is received.

Next, taking an optional consensus algorithm as an example, a specific implementation process of the consensus operation in step S233' is described in detail.

Specifically, the preparation process of the consensus operation is as follows: first, the master node included in the first block chain (i.e., the bottom-layer block chain 000) generates a corresponding first pre-prepare message (i.e., a pre-prepare message) for the second transaction information, and broadcasts the first pre-prepare message to each slave node in the first block chain. Specifically, the master node included in the bottom-layer block chain 000 sequences received transactions, assigns a corresponding serial number to each transaction, and accordingly, the first pre-preparation message includes a first transaction serial number assigned by the first block chain to the second transaction information, and is used for uniquely identifying the transaction in each node included in the bottom-layer block chain 000. The master node contained in the second blockchain (i.e., the bottom-layer blockchain 002) then generates a corresponding second pre-prepare message for the second transaction information, which is broadcast to the various slave nodes in the second blockchain. Specifically, the master node included in the underlying block chain 002 sequences the received transactions, assigns a corresponding serial number to each transaction, and accordingly, the second pre-preparation message includes a second transaction serial number assigned to the second transaction information by the second block chain, which is used to uniquely identify the transaction in each node included in the underlying block chain 002. In this way, the preparation process of the consensus operation is completed, and then, in the execution process of the consensus operation, the master node and each slave node included in the first blockchain and the master node and each slave node included in the second blockchain jointly identify the second transaction information. Specifically, the execution process of the consensus operation specifically includes the following steps:

step one, after the master node and each slave node included in the first block chain confirm the first pre-preparation message, the master node and each slave node included in the first block chain and the master node and each slave node included in the second block chain send the first pre-preparation message (namely, the pre-preparation message); and the master node and each slave node in the second blockchain confirm the second preparation message and then send the second preparation message to the master node and each slave node in the first blockchain and the master node and each slave node in the second blockchain.

Step two, the node in the first block chain, which receives the first preparation message larger than the preset first threshold and the second preparation message larger than the preset second threshold, sends a first confirmation message (i.e. commit message) to the master node and each slave node included in the first block chain and the master node and each slave node included in the second block chain; and the node in the second block chain, which receives the first preparation message larger than the preset first threshold and the second preparation message larger than the preset second threshold, sends a second confirmation message to the master node and each slave node contained in the first block chain and the master node and each slave node contained in the second block chain. The first threshold and the second threshold may be set according to actual conditions, for example, when the first blockchain includes 3f +1 nodes in total, the first threshold may be set to 2f + 1; when the second blockchain includes 3k +1 nodes in total, the first threshold may be set to 2k +1(f and k are both natural numbers). In summary, the first threshold and the second threshold may be set according to the maximum tolerable number of error nodes in the network to ensure reliable operation of the system.

And step three, if the first block link receives a first confirmation message larger than a preset first threshold value and a second confirmation message larger than a preset second threshold value, and the second block link receives the first confirmation message larger than the preset first threshold value and the second confirmation message larger than the preset second threshold value, determining that the consensus result is successful.

For ease of understanding, fig. 4 shows a schematic diagram of the above-described consensus operation. In fig. 4, the first blockchain includes four nodes, i.e., 0, 1, 2, and 3, where 0 is a master node; the second blockchain also comprises four nodes of 0, 1, 2 and 3, wherein 0 is a main node. The master node is a consensus message sending node, the slave node is a consensus message voting node, and the master node and the slave node can be determined through election. Also, fig. 4 divides the entire consensus process into five stages. Prior to the consensus operation being performed, a client affiliated with the first blockchain sends an asset transfer request to the first blockchain. In the first stage of the consensus operation, the asset transfer request is broadcast to all nodes in the first blockchain, the first blockchain is responsible for verifying the validity of the asset transfer request, and after the verification is passed, the master node 0 in the first blockchain sends information corresponding to the asset transfer request to the master node 0 in the second blockchain. In the second stage of the consensus operation, the master node 0 in the first blockchain allocates a corresponding first transaction serial number to the second transaction information corresponding to the asset transfer request, packages and writes the second transaction information into the transaction list, generates a corresponding first pre-preparation message (i.e., pre-preparation message) for the second transaction information, and broadcasts the first pre-preparation message to each node in the first blockchain. Similarly, the master node 0 in the second blockchain assigns a corresponding second transaction serial number to the second transaction information corresponding to the asset transfer request, packages and writes the second transaction information into a transaction list, generates a corresponding second pre-preparation message (i.e., pre-preparation message) for the second transaction information, and broadcasts the second pre-preparation message to each node inside the second blockchain. In a third phase of the consensus operation, each node in the first blockchain verifies the first pre-preparation message, and if the verification passes, the node generates a first preparation message (namely, a prepare message) and broadcasts the first preparation message to all nodes included in the first blockchain and the second blockchain; similarly, each node in the second blockchain verifies the second pre-preparation message, and if the verification passes, the node generates a second preparation message (i.e., a prepare message) and broadcasts the second preparation message to all nodes included in the first blockchain and the second blockchain. In fig. 4, only node 1 in the first blockchain is taken as an example for illustration, and in fact, in the third stage, each node in the two blockchains performs an operation process similar to that of node 1. Of course, if a node fails to verify, the first/second prepare message will not be generated and broadcast. In the fourth stage of the consensus operation, each node in the first block chain judges whether the number of the received first preparation messages from other nodes is larger than a first threshold value or not, and whether the number of the received second preparation messages from other nodes is larger than a second threshold value or not, if so, the node generates a first confirmation message and broadcasts the first confirmation message to all nodes in the first block chain and the second block chain; similarly, each node in the second blockchain determines whether the number of the received first preparation messages from other nodes is greater than a first threshold value and whether the number of the received second preparation messages from other nodes is greater than a second threshold value, if so, the node generates a second confirmation message and broadcasts the second confirmation message to all nodes in the first blockchain and the second blockchain. Of course, if the number of first preparation messages received by a node in the first blockchain/second blockchain from other nodes is not greater than the first threshold, or the number of second preparation messages received by the node from other nodes is not greater than the second threshold, the node does not generate and broadcast the acknowledgement message. In fig. 4, only node 2 in the second blockchain is taken as an example for illustration, and in fact, in the fourth stage, each node in the two blockchains performs a similar operation process as node 2. In the fifth stage of the consensus operation, if each node judges that the number of the received first confirmation messages from other nodes is greater than the first threshold value and the number of the received second confirmation messages from other nodes is greater than the second threshold value, the consensus operation is confirmed to be successful, and the transaction is confirmed and accounted in the subsequent steps.

Step S234': and if the consensus result is successful, the first block chain and the second block chain respectively carry out accounting on the second transaction information.

Specifically, each node in the first block chain records second transaction information corresponding to the transaction into an account book of the first block chain; meanwhile, each node in the second block chain records second transaction information corresponding to the transaction into an account book of the second block chain. Therefore, the transaction is only recorded in the ledger of the first blockchain and the second blockchain, and is not recorded in the ledger of other unrelated blockchains, so that the scale of the ledger can be simplified, and the inquiry is facilitated. Moreover, the accuracy of the account can be improved by a synchronous accounting mode of the two related block chains.

In addition, in this embodiment, to facilitate the query, the method may further include the following steps: each block chain in the block chain system collects the transaction information corresponding to each digital asset generated by the block chain, and submits the collected transaction collection result to a higher-level block chain of the block chain, so that the higher-level block chain of the block chain determines the collected transaction information corresponding to the higher-level block chain of the block chain according to the transaction collection result submitted by at least one lower-level block chain corresponding to the higher-level block chain of the block chain; and/or each blockchain in the blockchain system receives the transaction summary result submitted by at least one lower-level blockchain corresponding to the blockchain, and determines the summary transaction information corresponding to the blockchain according to the transaction summary result submitted by at least one lower-level blockchain corresponding to the blockchain. For a block chain without an upper block chain in a block chain system, the block chain is only responsible for receiving a transaction summary result submitted by at least one lower block chain corresponding to the block chain, and determines summary transaction information corresponding to the block chain according to the transaction summary result submitted by the at least one lower block chain corresponding to the block chain. For example, for the top-level blockchain 0 in fig. 1, since the blockchain 0 is a root node and has no corresponding upper-level blockchain (also called a parent node), the top-level blockchain 0 is configured to receive the transaction summary results submitted by the three lower-level blockchains 00, 01, and 02 corresponding to the top-level blockchain 0, and determine the summary transaction information corresponding to the blockchain 0 according to the transaction summary results. In addition, for a block chain without a lower block chain in the block chain system, the block chain is only responsible for summarizing the transaction information corresponding to each digital asset generated by the block chain, and submitting the summarized transaction summary result to the upper block chain of the block chain. For example, in the bottom block chain 000 in fig. 1, since the block chain 000 is a leaf node and there is no corresponding lower block chain (also called child node), the bottom block chain 000 is used to collect the transaction information corresponding to each digital asset generated by the block chain and to submit the collected transaction result to the upper block chain 00 of the block chain. In addition, since any blockchain in the blockchain system performs operations related to transaction aggregation, each transaction in the blockchain system is finally aggregated to the root node in the system through cross-layer transaction aggregation operations.

For example, assume that the following three digital asset transfer operations are performed in common between the bottom-layer block chain 000 and the bottom-layer block chain 010:

000AA- - >010BB, which means: transferring, by asset holder a, a digital asset identified as 000AA with a home block chain of 000 to asset holder B, the transferred asset identified as 010BB, and the home block chain 010; the sum of the digital assets is 1000 yuan;

000A 'A' - >010B 'B', which has the meaning: transferring, by asset holder a, a digital asset identified as 000A 'and a home block chain of 000 to asset holder B, the transferred asset identified as 010B' and the home block chain of 010; the sum of the digital assets is 2000 yuan;

000A "A" - - >010B "B", which means: transferring, by asset holder a, a digital asset identified as 000A "and having a home block chain of 000 to asset holder B, the transferred asset identified as 010B" and having a home block chain of 010; the sum of the digital assets is 3000 yuan.

Correspondingly, the bottom-layer block chain 000 and the bottom-layer block chain 010 summarize the three digital asset transfer transactions, and submit the summarized transaction information to the corresponding upper-layer block chains 00 and 01. The upper block chain 00 determines the summarized transaction information corresponding to the block chain according to the transaction summarized results submitted by each lower block chain (including block chains 000, 001, 002) corresponding to the block chain. For example, assume that only the block chain 000 submits the summarized transaction information in the current time period of the three lower-level block chains corresponding to the block chain 00, and accordingly, the block chain 00 obtains the following summarized transaction information according to the summarized transaction information submitted by the block chain 000:

00CC- - >01DD has the meaning: transferring, by an asset holder A, a digital asset having an asset identification of 00CC and a home block chain of 00 to an asset holder B, the asset identification of the transferred digital asset being 01DD and the home block chain being 01; the amount of the digital assets is 6000 yuan. Wherein, the digital assets with the asset identification of 00CC and the home block chain of 00 are summarized assets obtained by summarizing the three digital assets (000AA, 000A 'A' and 000A 'A'); similarly, the digital asset whose asset identifier is 01DD and home block chain is 01 is a summarized asset obtained by summarizing the three digital assets (010BB, 010B', 010B ").

In addition, the blockchain 00 further provides the transaction information after the summary to its upper blockchain, so that its upper blockchain can generate the summary transaction information. Similarly, the processing procedure of blockchain 01 is similar, and is not described herein again. For example, in the above example, it is assumed that only the blockchains 00 and 01 submit the summarized transaction information in the current time period of the three lower-level blockchains corresponding to the blockchain 0, and accordingly, the blockchain 0 obtains the following summarized transaction information according to the summarized transaction information submitted by the blockchains 00 and 01:

0EE- - >0DD has the meaning: transferring the digital asset with the asset identifier of 0EE and the attribution block chain of 0 to an asset holder B by the asset holder A, wherein the asset identifier of the transferred digital asset is 0DD and the attribution block chain is 0; the amount of the digital assets is 6000 yuan. The digital assets with the asset identification of 0EE and the home block chain of 0 are summarized assets obtained by summarizing the digital assets 00 CC; similarly, the digital asset with the asset identifier of 0DD and the home block chain of 0 is a summarized asset obtained by summarizing the digital asset 01 DD.

In the above example, only the transaction summary between the blockchains 000 and 010 is taken as an example for explanation, and those skilled in the art can understand that the transaction summary operation occurs between each blockchain and its upper blockchains. Correspondingly, the superior block chain only needs to perform accounting on the summarized transaction information obtained after the summary. In addition, the summarizing operation is not limited to the digital asset transfer operation, but also includes summarizing various operations such as new creation operation and destruction operation of the digital asset.

Therefore, by the mode, the hierarchical management of the account book is realized, and because the management institution at the upper layer does not usually care about the details of each small transaction among the users at the bottom layer, but only care about the transaction record of the lower institution directly subordinate to the management institution, the mode better meets the actual management requirement. Moreover, the account book is split and classified, so that on one hand, the total cost of the account book can be simplified, and on the other hand, the account book is very convenient and efficient to query according to the levels.

In addition, an embodiment of the present invention further provides a blockchain system for implementing a digital asset transaction, where the blockchain system is a tree-shaped distributed blockchain system including a plurality of hierarchical levels of blockchains, and the blockchain system at least includes:

a first blockchain adapted to receive a digital asset transaction request from a client, determine a digital asset corresponding to the digital asset transaction request;

judging whether a home block chain corresponding to the digital asset is the first block chain;

if so, the first blockchain processes the digital asset transaction request; if not, the first blockchain rejects the digital asset transaction request;

wherein, the attribution block chain corresponding to the digital assets is the block chain generating the digital assets.

Optionally, the first blockchain is specifically adapted to:

receiving a digital asset generation request from a client, allocating a corresponding asset identifier for a digital asset corresponding to the digital asset generation request, and generating and storing block chain signature information generated aiming at the asset identifier of the digital asset; and/or the presence of a gas in the gas,

judging whether the first block chain stores block chain signature information generated aiming at the asset identification of the digital asset, if so, determining that a home block chain corresponding to the digital asset is the first block chain; if not, determining that the home blockchain corresponding to the digital asset is not the first blockchain.

Optionally, when the digital asset transaction request is an asset transfer request, the first blockchain is specifically adapted to:

determining a block chain corresponding to an asset transfer party contained in the asset transfer request;

if the block chain corresponding to the asset transfer party is the first block chain, all nodes in the first block chain perform consensus on the first transaction information corresponding to the asset transfer request, and if the consensus result is successful, the first transaction information is booked in the first block chain.

Optionally, the first transaction information specifically includes:

asset holder information prior to asset transfer for providing to the first blockchain to destroy digital assets corresponding to the digital asset transaction request in the first blockchain;

and the asset holder information after asset transfer is used for providing the information to the first block chain so as to generate digital assets equivalent to the destroyed digital assets in the first block chain, and setting corresponding asset identification and asset holder information for the generated digital assets equivalent to the destroyed digital assets.

Optionally, the system further comprises: a second blockchain, when the digital asset transaction request is an asset transfer request, the first blockchain being specifically adapted to:

if the block chain corresponding to the asset transfer party is a second block chain, sending second transaction information corresponding to the asset transfer request to the second block chain;

consensus is made by the first blockchain and the second blockchain together for the second transaction information;

and if the consensus result of the consensus is successful, the first block chain and the second block chain are respectively booked for the second transaction information.

Optionally, the second transaction information specifically includes:

and the asset holder information after asset transfer is used for providing the asset holder information to the second block chain, so that digital assets equivalent to the destroyed digital assets are generated in the second block chain, and asset identification and asset holder information corresponding to the generated digital assets equivalent to the destroyed digital assets are set.

Optionally, the second blockchain is further adapted to: generating and storing blockchain signature information generated for the generated asset identification of the digital asset equivalent to the destroyed digital asset.

Optionally, the first block chain further includes: a master node and a slave node; the second blockchain further comprises: a master node and a slave node;

the main node contained in the first block chain is used for sending the second transaction information to the second block chain;

the master node included in the first blockchain is further configured to generate a corresponding first pre-preparation message for the second transaction information, and broadcast the first pre-preparation message to each slave node in the first blockchain;

the master node included in the second blockchain is used for generating a corresponding second pre-preparation message aiming at the second transaction information and broadcasting the second pre-preparation message to each slave node in the second blockchain;

the master node and each slave node included in the first blockchain, and the master node and each slave node included in the second blockchain are used for commonly recognizing the second transaction information.

Optionally, the master node and each slave node included in the first blockchain are specifically configured to send a first preparation message to the master node and each slave node included in the first blockchain and the master node and each slave node included in the second blockchain after the first preparation message is confirmed;

the master node and each slave node included in the second blockchain are specifically configured to send a second preparation message to the master node and each slave node included in the first blockchain and the master node and each slave node included in the second blockchain after the second preparation message is confirmed;

a node in the first block chain, which receives a first preparation message larger than a preset first threshold and a second preparation message larger than a preset second threshold, is configured to send first acknowledgement messages to a master node and each slave node included in the first block chain and the master node and each slave node included in the second block chain;

the node in the second block chain, which receives the first preparation message larger than the preset first threshold and the second preparation message larger than the preset second threshold, is configured to send a second acknowledgement message to the master node and each slave node included in the first block chain and the master node and each slave node included in the second block chain;

and if the first block link receives a first confirmation message larger than a preset first threshold value and a second confirmation message larger than a preset second threshold value, and the second block link receives the first confirmation message larger than the preset first threshold value and the second confirmation message larger than the preset second threshold value, determining that the consensus result is successful.

Optionally, the first pre-preparation message includes a first transaction serial number allocated by the first block chain to the second transaction information; the second pre-preparation message includes a second transaction serial number allocated to the second transaction information by the second blockchain.

Optionally, if the digital asset has a corresponding asset holder signature, asset key and/or asset usage condition script, the first blockchain is specifically configured to:

and judging whether a client submitting the digital asset transaction request is legal or not according to the asset holder signature, the asset key and/or the asset use condition script, and if so, processing the digital asset transaction request.

Optionally, the block chain system is divided into a plurality of levels from top to bottom, and specifically includes: a top level block chain at a top level of the plurality of levels, a middle level block chain at a middle level of the plurality of levels, a plurality of bottom level block chains at a bottom level of the plurality of levels; wherein the number of levels of the top level and the bottom level is 1, respectively, the number of levels of the middle level is N, and N is an integer greater than or equal to 0; wherein each blockchain is consensus and accounting for transactions associated with the blockchain.

Optionally, each blockchain in the blockchain system is further configured to: summarizing the transaction information corresponding to each digital asset generated by the block chain, and submitting the summarized transaction summarizing result to an upper-level block chain of the block chain so that the upper-level block chain of the block chain can determine the summarized transaction information corresponding to the upper-level block chain of the block chain according to the transaction summarizing result submitted by at least one lower-level block chain corresponding to the upper-level block chain of the block chain; and/or the presence of a gas in the gas,

each blockchain in the blockchain system is further configured to: and receiving a transaction summary result submitted by at least one subordinate block chain corresponding to the block chain, and determining summary transaction information corresponding to the block chain according to the transaction summary result submitted by the at least one subordinate block chain corresponding to the block chain.

Optionally, the digital asset transaction request comprises: an asset consumption request for consuming a digital asset; and, the digital asset is a one-at-a-time digital asset.

The specific structure and implementation details of the system may refer to the description of the corresponding parts and method embodiments above, and are not repeated here.

In summary, in the digital asset transaction method and system based on the blockchain system provided by the present invention, since the blockchain system is a tree-shaped distributed blockchain system including a plurality of levels of blockchains, each blockchain in the system can independently process transactions related to the blockchain by dividing the levels. And the block chain of the generated digital assets is used as the home block chain of the digital assets, so that each digital asset only corresponds to a unique home block chain and related transaction operation can be carried out only through the home block chain, thereby not only being beneficial to realizing concurrence of multiple digital asset transactions and improving transaction efficiency, but also obviously improving the safety of the digital assets and avoiding the risk of the digital assets being attacked by irrelevant malicious block chains. In addition, the consensus algorithm in this embodiment can quickly and accurately achieve consensus only in the two blockchains associated with the transaction. And the verification of the digital assets can be effectively realized on the tree-shaped distributed account book through the concept of the home block chain, and the problem of double flowers that the digital assets are used at one time (namely, the same asset is spent for two times) is avoided.

This approach is particularly useful for transactions that use a digital asset at a time, which can only be used once; in addition, the method can also realize cross-chain transaction among the digital assets, and the digital assets before and after the cross-chain transaction is executed respectively correspond to different attribution block chains, so that the safety of the assets is improved.

The algorithms and displays presented herein are not inherently related to any particular computer, virtual machine, or other apparatus. Various general purpose systems may also be used with the teachings herein. The required structure for constructing such a system will be apparent from the description above. Moreover, the present invention is not directed to any particular programming language. It is appreciated that a variety of programming languages may be used to implement the teachings of the present invention as described herein, and any descriptions of specific languages are provided above to disclose the best mode of the invention.

In the description provided herein, numerous specific details are set forth. It is understood, however, that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description.

Similarly, it should be appreciated that in the foregoing description of exemplary embodiments of the invention, various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of one or more of the various inventive aspects. However, the disclosed method should not be interpreted as reflecting an intention that: that the invention as claimed requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment. Thus, the claims following the detailed description are hereby expressly incorporated into this detailed description, with each claim standing on its own as a separate embodiment of this invention.

Those skilled in the art will appreciate that the modules in the device in an embodiment may be adaptively changed and disposed in one or more devices different from the embodiment. The modules or units or components of the embodiments may be combined into one module or unit or component, and furthermore they may be divided into a plurality of sub-modules or sub-units or sub-components. All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and all of the processes or elements of any method or apparatus so disclosed, may be combined in any combination, except combinations where at least some of such features and/or processes or elements are mutually exclusive. Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise.

Furthermore, those skilled in the art will appreciate that while some embodiments described herein include some features included in other embodiments, rather than other features, combinations of features of different embodiments are meant to be within the scope of the invention and form different embodiments. For example, in the following claims, any of the claimed embodiments may be used in any combination.

The various component embodiments of the invention may be implemented in hardware, or in software modules running on one or more processors, or in a combination thereof. Those skilled in the art will appreciate that a microprocessor or Digital Signal Processor (DSP) may be used in practice to implement some or all of the functions of some or all of the components in a network transaction apparatus based on a blockchain system according to embodiments of the present invention. The present invention may also be embodied as apparatus or device programs (e.g., computer programs and computer program products) for performing a portion or all of the methods described herein. Such programs implementing the present invention may be stored on computer-readable media or may be in the form of one or more signals. Such a signal may be downloaded from an internet website or provided on a carrier signal or in any other form.

It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word "comprising" does not exclude the presence of elements or steps not listed in a claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The invention may be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means may be embodied by one and the same item of hardware. The usage of the words first, second and third, etcetera do not indicate any ordering. These words may be interpreted as names.

The invention discloses A1. a digital asset transaction method based on a blockchain system, wherein the blockchain system is a tree-shaped distributed blockchain system comprising a plurality of levels of blockchains, and the method comprises the following steps:

the first block chain receives a digital asset transaction request from a client and determines a digital asset corresponding to the digital asset transaction request;

A2. The method of a1, wherein the step of the first blocklink receiving a digital asset transaction request from a client is preceded by the step of further comprising the steps of:

the step of determining whether the home block chain corresponding to the digital asset is the first block chain specifically includes:

A3. The method according to a1 or 2, wherein, when the digital asset transaction request is an asset transfer request, the step of the first blockchain processing the digital asset transaction request specifically comprises:

A4. The method according to a3, wherein the first transaction information specifically includes:

A5. The method according to any of a1-4, wherein, when the digital asset transaction request is an asset transfer request, the step of the first blockchain processing the digital asset transaction request specifically comprises:

if the block chain corresponding to the asset transfer party is a second block chain, the first block chain sends second transaction information corresponding to the asset transfer request to the second block chain;

the first blockchain and the second blockchain commonly agree on the second transaction information;

A6. The method according to a5, wherein the second transaction information specifically includes:

A7. The method according to a6, wherein the step of setting the corresponding asset identification and asset holder information for the generated digital asset equivalent to the destroyed digital asset further comprises:

the second blockchain generates and stores blockchain signature information generated for asset identifications of the generated digital assets that are equivalent to the destroyed digital assets.

A8. The method according to any one of a5-7, wherein the step of the first blockchain sending the second transaction information corresponding to the asset transfer request to the second blockchain specifically includes:

the main node contained in the first blockchain sends the second transaction information to the second blockchain;

the step of commonly recognizing the second transaction information by the first blockchain and the second blockchain specifically includes:

a master node contained in the first blockchain generates a corresponding first pre-preparation message aiming at the second transaction information, and broadcasts the first pre-preparation message to each slave node in the first blockchain;

the master node contained in the second blockchain generates a corresponding second pre-preparation message aiming at the second transaction information, and broadcasts the second pre-preparation message to each slave node in the second blockchain;

the master node and each slave node included in the first blockchain and the master node and each slave node included in the second blockchain commonly identify the second transaction information.

A9. The method of A8, wherein the step of commonly recognizing the second transaction information by the master node and each slave node included in the first blockchain and the master node and each slave node included in the second blockchain specifically comprises:

after confirming the first pre-preparation message, the master node and each slave node included in the first blockchain send a first preparation message to the master node and each slave node included in the first blockchain and the master node and each slave node included in the second blockchain;

after confirming the second pre-preparation message, the master node and each slave node included in the second blockchain send a second preparation message to the master node and each slave node included in the first blockchain and the master node and each slave node included in the second blockchain;

a node in the first block chain, which receives a first preparation message larger than a preset first threshold and a second preparation message larger than a preset second threshold, sends a first confirmation message to a master node and each slave node included in the first block chain and the master node and each slave node included in the second block chain;

a node in the second block chain, which receives a first preparation message larger than a preset first threshold and a second preparation message larger than a preset second threshold, sends a second confirmation message to a master node and each slave node included in the first block chain and the master node and each slave node included in the second block chain;

A10. The method according to A8 or 9, wherein the first pre-preparation message includes a first transaction sequence number allocated by the first blockchain to the second transaction information; the second pre-preparation message includes a second transaction serial number allocated to the second transaction information by the second blockchain.

A11. The method of any of a1-10, wherein the digital asset has a corresponding asset holder signature, asset key, and/or asset usage condition script, the step of processing the digital asset transaction request by the first blockchain specifically comprises:

A12. The method according to any of a1-11, wherein the blockchain system is divided into a plurality of levels from top to bottom, comprising: a top level block chain at a top level of the plurality of levels, a middle level block chain at a middle level of the plurality of levels, a plurality of bottom level block chains at a bottom level of the plurality of levels; wherein the number of levels of the top level and the bottom level is 1, respectively, the number of levels of the middle level is N, and N is an integer greater than or equal to 0;

wherein each blockchain is consensus and accounting for transactions associated with the blockchain.

A13. The method according to any of a1-12, wherein the method further comprises: each block chain in the block chain system collects the transaction information corresponding to each digital asset generated by the block chain, and submits the collected transaction collection result to an upper-level block chain of the block chain, so that the upper-level block chain of the block chain determines the collected transaction information corresponding to the upper-level block chain of the block chain according to the transaction collection result submitted by at least one lower-level block chain corresponding to the upper-level block chain of the block chain; and/or the presence of a gas in the gas,

each blockchain in the blockchain system receives the transaction summary result submitted by at least one lower-level blockchain corresponding to the blockchain, and determines the summary transaction information corresponding to the blockchain according to the transaction summary result submitted by at least one lower-level blockchain corresponding to the blockchain.

A14. The method of any of a1-13, wherein the digital asset transaction request includes: an asset consumption request for consuming a digital asset; and, the digital asset is a one-at-a-time digital asset.

The invention also discloses a blockchain system for realizing digital asset transaction, wherein the blockchain system is a tree-shaped distributed blockchain system comprising a plurality of levels of blockchains, and the blockchain system at least comprises:

B16. The system of B15, wherein the first blockchain is specifically adapted to:

B17. The system of B15 or 16, wherein, when the digital asset transaction request is an asset transfer request, the first blockchain is specifically adapted to:

B18. The system according to B17, wherein the first transaction information specifically includes:

B19. The system of any of B15-18, wherein the system further comprises: a second blockchain, when the digital asset transaction request is an asset transfer request, the first blockchain being specifically adapted to:

B20. The system according to B19, wherein the second transaction information specifically includes:

B21. The system of B20, wherein the second blockchain is further adapted to: generating and storing blockchain signature information generated for the generated asset identification of the digital asset equivalent to the destroyed digital asset.

B22. The system of any of B15-21, wherein the first blockchain further comprises: a master node and a slave node; the second blockchain further comprises: a master node and a slave node;

B23. The system of B22, wherein,

the master node and each slave node included in the first blockchain are specifically configured to send a first preparation message to the master node and each slave node included in the first blockchain and the master node and each slave node included in the second blockchain after the first preparation message is confirmed;

B24. The system according to B22 or 23, wherein the first pre-preparation message includes a first transaction sequence number assigned by the first blockchain to the second transaction information; the second pre-preparation message includes a second transaction serial number allocated to the second transaction information by the second blockchain.

B25. The system of any of B15-24, wherein the digital asset has a corresponding asset holder signature, asset key, and/or asset usage condition script, then the first blockchain is specifically configured to:

B26. The system according to any of B15-25, wherein the blockchain system is divided into a plurality of levels from top to bottom, comprising: a top level block chain at a top level of the plurality of levels, a middle level block chain at a middle level of the plurality of levels, a plurality of bottom level block chains at a bottom level of the plurality of levels; wherein the number of levels of the top level and the bottom level is 1, respectively, the number of levels of the middle level is N, and N is an integer greater than or equal to 0;

B27. The system of any of B15-26, wherein each blockchain in the blockchain system is further configured to: summarizing the transaction information corresponding to each digital asset generated by the block chain, and submitting the summarized transaction summarizing result to an upper-level block chain of the block chain so that the upper-level block chain of the block chain can determine the summarized transaction information corresponding to the upper-level block chain of the block chain according to the transaction summarizing result submitted by at least one lower-level block chain corresponding to the upper-level block chain of the block chain; and/or the presence of a gas in the gas,

B28. The system of any of B15-27, wherein the digital asset transaction request comprises: an asset consumption request for consuming a digital asset; and, the digital asset is a one-at-a-time digital asset.

Claims

1. A method for digital asset transaction based on a blockchain system, wherein the blockchain system is a tree-shaped distributed blockchain system comprising a plurality of levels of blockchains, the method comprising:

2. The method of claim 1, wherein the first blockchain, prior to the step of receiving a digital asset transaction request from a client, further comprises the steps of:

3. The method of claim 1, wherein, when the digital asset transaction request is an asset transfer request, the step of the first blockchain processing the digital asset transaction request specifically comprises:

4. The method according to claim 3, wherein the first transaction information specifically includes:

5. The method of claim 1, wherein, when the digital asset transaction request is an asset transfer request, the step of the first blockchain processing the digital asset transaction request specifically comprises:

6. The method according to claim 5, wherein the second transaction information specifically includes:

7. The method of claim 6, wherein said step of setting the corresponding asset identification and asset holder information for the generated digital asset equivalent to the destroyed digital asset further comprises:

8. The method of claim 5, wherein the step of the first blockchain sending the second transaction information corresponding to the asset transfer request to the second blockchain specifically comprises:

9. The method of claim 8, wherein the step of commonly recognizing the second transaction information by the master node and each slave node included in the first blockchain and the master node and each slave node included in the second blockchain comprises:

10. The method according to claim 8 or 9, wherein the first pre-preparation message includes a first transaction sequence number allocated by the first blockchain for the second transaction information; the second pre-preparation message includes a second transaction serial number allocated to the second transaction information by the second blockchain.

11. The method of claim 1, wherein the digital asset has a corresponding asset holder signature, asset key and/or asset usage condition script, the step of the first blockchain processing the digital asset transaction request specifically comprises:

12. The method according to any of claims 1-9, wherein the blockchain system is divided into a plurality of levels from top to bottom, including: a top level block chain at a top level of the plurality of levels, a middle level block chain at a middle level of the plurality of levels, a plurality of bottom level block chains at a bottom level of the plurality of levels; wherein the number of levels of the top level and the bottom level is 1, respectively, the number of levels of the middle level is N, and N is an integer greater than or equal to 0;

13. The method of any of claims 1-9, wherein the method further comprises: each block chain in the block chain system collects the transaction information corresponding to each digital asset generated by the block chain, and submits the collected transaction collection result to an upper-level block chain of the block chain, so that the upper-level block chain of the block chain determines the collected transaction information corresponding to the upper-level block chain of the block chain according to the transaction collection result submitted by at least one lower-level block chain corresponding to the upper-level block chain of the block chain; and/or the presence of a gas in the gas,

14. The method of any of claims 1-9, wherein the digital asset transaction request comprises: an asset consumption request for consuming a digital asset; and, the digital asset is a one-at-a-time digital asset.

15. A blockchain system for implementing a digital asset transaction, wherein the blockchain system is a tree-shaped distributed blockchain system comprising a plurality of levels of blockchains, and wherein at least:

16. The system of claim 15, wherein the first blockchain is specifically adapted to:

17. The system of claim 15, wherein, when the digital asset transaction request is an asset transfer request, the first blockchain is specifically adapted to:

18. The system of claim 17, wherein the first transaction information specifically includes:

19. The system of claim 15, wherein the system further comprises: a second blockchain, when the digital asset transaction request is an asset transfer request, the first blockchain being specifically adapted to:

20. The system of claim 19, wherein the second transaction information specifically includes:

21. The system of claim 20, wherein the second blockchain is further adapted to: generating and storing blockchain signature information generated for the generated asset identification of the digital asset equivalent to the destroyed digital asset.

22. The system of claim 19, wherein the first blockchain further comprises: a master node and a slave node; the second blockchain further comprises: a master node and a slave node;

23. The system of claim 22, wherein,

24. The system according to claim 22 or 23, wherein the first pre-preparation message includes a first transaction sequence number assigned by the first blockchain to the second transaction information; the second pre-preparation message includes a second transaction serial number allocated to the second transaction information by the second blockchain.

25. The system of any of claims 15-23, wherein the digital asset has a corresponding asset holder signature, asset key, and/or asset usage condition script, the first blockchain is specifically configured to:

26. The system according to any of claims 15-23, wherein the blockchain system is divided into a plurality of levels from top to bottom, including: a top level block chain at a top level of the plurality of levels, a middle level block chain at a middle level of the plurality of levels, a plurality of bottom level block chains at a bottom level of the plurality of levels; wherein the number of levels of the top level and the bottom level is 1, respectively, the number of levels of the middle level is N, and N is an integer greater than or equal to 0;

27. The system of any of claims 15-23, wherein each blockchain in the blockchain system is further configured to: summarizing the transaction information corresponding to each digital asset generated by the block chain, and submitting the summarized transaction summarizing result to an upper-level block chain of the block chain so that the upper-level block chain of the block chain can determine the summarized transaction information corresponding to the upper-level block chain of the block chain according to the transaction summarizing result submitted by at least one lower-level block chain corresponding to the upper-level block chain of the block chain; and/or the presence of a gas in the gas,

28. The system of any of claims 15-23, wherein the digital asset transaction request comprises: an asset consumption request for consuming a digital asset; and, the digital asset is a one-at-a-time digital asset.