KR102381697B1 - Method and system for servicing blockchain-based property trade - Google Patents

Abstract

A blockchain-based goods contract service method and a blockchain-based goods contract service device are disclosed. According to an embodiment of the present invention, a blockchain-based goods contract service method includes: as goods data is input from a seller terminal, transmitting the goods data to an intermediary terminal that satisfies a prescribed condition; Encrypting the goods data returned after being authenticated by the intermediary terminal in a block chain method and storing it in a block chain sector; and connecting the buyer terminal that retrieves the goods data and the seller terminal through the block chain sector.

Description

Blockchain-based goods contract service method and device {METHOD AND SYSTEM FOR SERVICING BLOCKCHAIN-BASED PROPERTY TRADE}

The present invention registers a reliable intermediary using a smart contract that operates on the Ethereum blockchain and uses the smart contract in the value verification and contract process of goods, so that the registration contents of goods, proposals, and contract processes are transferred to the blockchain. It relates to a method and device for a blockchain-based goods contract service that ensures the reliability of the contract process by registering.

The types of goods traded in accordance with changes in modern consumption patterns are rapidly increasing. This change is probably due to the spread of the sharing economy contract method, such as rental and leasing, centered on ‘sharing’ rather than ‘ownership’ centered sales contract. Due to the increase in goods, consumers have gained the advantage of being able to use desired services and goods at a more reasonable price, but in the case of artworks and creative works, it is difficult for consumers to determine the appropriate value of goods, and the contract There is also a problem that it is difficult to guarantee its own professionalism and reliability. In order to solve the problem, if a broker with expertise in the type of goods makes an appropriate value judgment and mediates the contract process properly, both the seller and the buyer will be able to conclude a reliable contract. As access to various goods has improved, if these problems are resolved, the sharing economy market is expected to develop more stably than it is now.

Goods contract services using existing block chains focus on the reliability provided by block chains, and are oriented in a way that does not use a contract broker or medium. As a result, existing services can prevent forgery and falsification of registered goods information through the block chain, but there are problems with the reliability of the goods themselves and the contract process.

Therefore, there is an urgent need for a new technique to provide a blockchain-based goods contract service through a reliable intermediary.

An embodiment of the present invention aims to provide a method and apparatus for a blockchain-based goods contract service, which registers a reliable intermediary using a smart contract operating on the Ethereum blockchain and utilizes it in the value verification and contract process of goods do it with

In addition, an embodiment of the present invention aims to ensure the reliability of the contract process by registering the registration details of goods, proposals, and contract process in the block chain.

In addition, the embodiment of the present invention aims to ensure the reliability of the registered data, since all operation processes are registered in the smart contract and stored in the transaction history of the Ethereum blockchain.

In addition, the embodiment of the present invention aims to enable the user to more safely control the contract process because the entire process of registration, proposal, and contract is operated by a state machine-based smart contract.

According to an embodiment of the present invention, a blockchain-based goods contract service method includes: as goods data is input from a seller terminal, transmitting the goods data to an intermediary terminal that satisfies a prescribed condition; Encrypting the goods data returned after being authenticated by the intermediary terminal in a block chain method and storing it in a block chain sector; and connecting the buyer terminal that retrieves the goods data and the seller terminal through the block chain sector.

In addition, according to an embodiment of the present invention, a block chain-based goods contract service apparatus includes an interface unit that, as goods data is input from a seller terminal, transmits the goods data to an intermediary terminal that satisfies a prescribed condition; and an encryption that connects the buyer terminal and the seller terminal, which encrypts the goods data that are authenticated by the intermediary terminal and returns them in a block chain method, stores them in a block chain sector, and retrieves the goods data through the block chain sector It can be configured including a processing unit.

According to an embodiment of the present invention, a method and apparatus for a blockchain-based goods contract service are provided, which register a reliable intermediary using a smart contract operating on the Ethereum blockchain and utilize it in the value verification and contract process of goods. can

In addition, according to an embodiment of the present invention, the reliability of the contract process can be guaranteed by registering the contents of registration of goods, proposals, and contract processes in the block chain.

In addition, according to an embodiment of the present invention, since all operation processes are registered in the smart contract and stored in the transaction history of the Ethereum block chain, the reliability of the registered data can be guaranteed.

In addition, according to an embodiment of the present invention, since the entire process of registration, proposal, and contract is operated by a state machine-based smart contract, the user can more safely control the contract process.

1 is a block diagram showing the configuration of a block chain-based goods contract service apparatus according to an embodiment of the present invention.
2 is a view for explaining the system structure of Trade B according to the present invention.
3 is a diagram for explaining an operation flow of a purchase proposal according to the present invention.
4 and 5 are diagrams for explaining the operation flow of the contract service provided by Trade B according to the present invention.
6 is a flowchart illustrating a blockchain-based goods contract service method according to an embodiment of the present invention.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. However, since various changes may be made to the embodiments, the scope of the patent application is not limited or limited by these embodiments. It should be understood that all modifications, equivalents and substitutes for the embodiments are included in the scope of the rights.

The terms used in the examples are used for the purpose of description only, and should not be construed as limiting. The singular expression includes the plural expression unless the context clearly dictates otherwise. In this specification, terms such as "comprise" or "have" are intended to designate that a feature, number, step, operation, component, part, or a combination thereof described in the specification exists, but one or more other features It should be understood that this does not preclude the existence or addition of numbers, steps, operations, components, parts, or combinations thereof.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the embodiment belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or excessively formal meaning unless explicitly defined in the present application. does not

In addition, in the description with reference to the accompanying drawings, the same components are given the same reference numerals regardless of the reference numerals, and the overlapping description thereof will be omitted. In describing the embodiment, if it is determined that a detailed description of a related known technology may unnecessarily obscure the gist of the embodiment, the detailed description thereof will be omitted.

The blockchain-based goods contract service method and apparatus of the present invention register a reliable broker in the blockchain to solve the problems of the existing blockchain-based goods contract service, and the registered broker certifies the value of goods and the appropriateness of the contract Blockchain-based goods contract service (hereinafter abbreviated as Trade B) can be provided.

Trade B can provide three services for contracting goods.

The first may be a service in which a seller registers a specific good. At this time, the registered goods are recorded in the block chain after the broker's value verification. For service operation, Trade B operates a smart contract that registers and manages reliable brokers, and for specific goods whose value has been verified, information of goods and information of brokers who performed value verification can be stored in the block chain.

The second may be a service in which a buyer offers a purchase condition for a specific good. When a buyer searches for a registered product and wants to purchase it, Trade B can propose a purchase condition to the seller. A seller may receive offers from multiple buyers for a particular good, and may select and accept one of them.

A third function may be a service for concluding a contract based on an offer accepted by the seller. In Trade B, a broker can draft a contract based on the proposal, obtain confirmation from the seller and buyer, and complete the final contract to conclude a contract.

These services are defined by state charts and can be precisely controlled according to the state by operating on a state machine basis. The smart contract responsible for the functions of Trade B is a broker contract that registers and manages reliable brokers, a property contract that manages specific goods information and purchase conditions proposals and contract details, and a property factory contract that creates a property contract when new goods are registered. can be configured. Each contract is deployed on the blockchain and can operate according to Trade B's services. Trade B was developed based on the Ethereum blockchain to contain information of goods and contracts in smart contracts. In addition, the smart contract was developed in the Solidity language, and its function is being verified in a private blockchain network composed of Geth nodes.

Blockchain technology is a data forgery prevention technology based on distributed computing technology. The blockchain technology stores the transaction containing the user's request in the unit of data called a block, and the transaction is copied to the nodes constituting the distributed network and stored in the form of a chain. Blockchain technology uses a hash function that maps data of arbitrary length to data of fixed length. The hash function has a characteristic that a completely different result value is output even if only a part of the input value is changed, so that the input value cannot be inferred based on the output value. Blockchain technology guarantees integrity through the features of a hash function, and uses an asymmetric key encryption method that uses public/private keys to ensure confidentiality. Through this, blockchain technology verifies transactions and compares hash values to prevent forgery and falsification of data.

The first-generation blockchain, Bitcoin, used blockchain technology as a distributed ledger to store transaction records, and the second-generation blockchain, Ethereum, introduced smart contracts and introduced the concept of a 'programmable blockchain'. As a result, it became possible to develop distributed applications controlled by logical operations, and 3rd generation block chain technologies are emerging in the form of supplementing the shortcomings of existing technologies.

A smart contract is a concept introduced in Ethereum, and it is an operation function that is automatically performed according to conditions on the block chain, unlike the existing contract method in which a person faces a written contract. In Ethereum, it is written using Solidity, a Java-based language provided by itself. Ethereum distributes the ABI (Application Binary Interface) created by compiling the smart contract to the blockchain network, and when a user sends a transaction for the smart contract, it performs a function according to the content and conditions. As each line of the smart contract is executed, a fee is generated in Ethereum, and the limit of the fee can be specified on the network. With Ethereum, it is possible to develop distributed applications that operate according to a logical structure using smart contracts.

The sharing economy changes the concept of goods from 'ownership' to 'share', and can mean an economy based on collaborative consumption in which goods produced once are shared and used by several people. The sharing economy has emerged as a measure to reduce overconsumption and rational consumption of necessary goods. In recent years, a number of companies (platforms) have been established that use intermediaries to coordinate goods and consumers, and replace this role. Examples of sharing economy business companies include vehicle sharing services and rental housing services. Familiar places such as libraries and PC rooms can also be viewed as part of the sharing economy.

1 is a block diagram showing the configuration of a block chain-based goods contract service apparatus according to an embodiment of the present invention.

Referring to FIG. 1 , a block chain-based goods contract service apparatus 100 according to an embodiment of the present invention may include an interface unit 110 and a cryptographic processing unit 120 . In addition, the block chain-based goods contract service apparatus 100 may be configured by adding the creation unit 130 according to an embodiment.

First, as the goods data is input from the seller terminal, the interface unit 110 transmits the goods data to the broker terminal that satisfies the prescribed conditions. That is, the interface unit 110 may serve to determine an intermediary for buying and selling goods as data about goods to be sold is received, and to transmit the data to the terminal of the intermediary.

Here, goods have a value and are objects that can be bought and sold at a price, for example, commodities, real estate, etc. may be exemplified.

In selecting an intermediary, the interface unit 110 may select a specific number of intermediaries satisfying a condition from among intermediary groups specialized in the category of inputted goods data. The condition may be whether or not a license is owned, whether a transaction history is there, whether or not capital / equipment is possessed. For example, if the goods data is about 'real estate', the interface unit 110 holds a certified real estate agent license, and the real estate brokerage history is '10 Two or more brokers can be selected from the broker group.

The broker terminal that has received the goods data determines whether or not to authenticate the goods data after determining whether the goods data has a significant enough value to transact, whether the seller who entered the goods data can be trusted, and the like, and the present invention will return to the blockchain-based goods contract service device 100 of

When the goods data is returned as unauthenticated because it does not meet the standards, the block chain-based goods contract service apparatus 100 may notify the seller terminal of the impossibility of intermediary for the goods data.

On the other hand, when the goods data is authenticated by achieving the standard, the block chain-based goods contract service device 100 performs brokerage processing for the goods data based on the blockchain through the cryptographic processing unit 120 to be described later.

The encryption processing unit 120 encrypts the goods data returned after being authenticated by the intermediary terminal in a block chain method and stores the encrypted data in the block chain sector. That is, the cryptographic processing unit 120 encrypts the intermediary good data based on the block chain and registers it on the block chain network, so that the goods data can be propagated in an encrypted state on the block chain network.

In addition, the cryptographic processing unit 120 may connect the buyer terminal searching for the goods data and the seller terminal through the block chain sector. That is, the cryptographic processing unit 120 may play a role of matching the seller terminal and the buyer terminal as a purchase intention is input in the purchaser terminal that has searched for the goods data on the block chain network.

Through this, the block chain-based goods contract service apparatus 100 may perform mediation processing between the seller terminal and the buyer terminal with respect to the goods data.

In the process of encrypting the goods data input by the seller terminal based on the block chain, the interface unit 110 may collect broker information about the broker terminal in conjunction with the return of the goods data. That is, the interface unit 110 may additionally receive information on the broker who brokers the goods data that is authenticated by the broker terminal so that the brokerage transaction is possible.

Thereafter, the encryption processing unit 120 encrypts the collected broker information together with the goods data and stores it in the block chain sector. That is, the cryptographic processing unit 120 may play a role of encrypting information about an intermediary that is intermediary by authenticating the goods data, matching it with the goods data, and storing it in the block chain sector.

Through this, the block chain-based goods contract service device 100 can improve the reliability of the brokerage transaction by clarifying the middleman who processes the goods data.

Also, the interface unit 110 may receive a purchase condition related to the goods data from the purchaser terminal. That is, the interface unit 110 may search for the goods data and receive a purchase condition required for purchase from a purchaser intending to purchase.

Here, the purchase condition may be, for example, adjustment of a reduction in the sale price suggested by the seller, adjustment of the lease start time, adjustment of the rental period, etc. when the goods are real estate.

The encryption processing unit 120 encrypts the purchase condition in the block chain method, stores it in the block chain sector, and provides the purchase condition to the seller terminal through the block chain sector, thereby providing the seller terminal with It is possible to determine whether to accept the purchase conditions by the That is, the cryptographic processing unit 120 transmits the purchase condition of the buyer to the seller based on the block chain, so that the seller can determine whether to accept the purchase condition.

Thereafter, after determining whether to accept the purchase condition registered by the purchaser terminal, the seller terminal may input it to the block chain-based goods contract service apparatus 100 .

As a result, the block chain-based goods contract service device 100 can perform an intermediary process that adjusts/coordinates the conditions for purchase through the goods data between the connected seller terminal and the buyer terminal based on the block chain. there is.

After the condition adjustment is made, the block chain-based goods contract service device 100 may create a contract based on the goods data.

To this end, the block chain-based goods contract service device 100 may be configured by adding the creation unit 130 .

The creation unit 130 creates contract data regarding the goods data for which the purchase condition is accepted by the seller terminal. That is, the writing unit 130 may play a role of writing contract data by writing the contents of the sales contract for the goods according to a prescribed abbreviation.

Here, the contract data may include, for example, information on the goods to be sold (location, size, use, etc.), information on the adjusted sale amount (including down payment), and a transfer schedule of the amount delivered to the seller.

After writing the contract data, the cryptographic processing unit 120 encrypts the contract data in the block chain method and stores it in a block chain sector, and through the block chain sector, the contract data is transferred to the connected purchaser terminal and the It is provided to the seller terminal. That is, the cryptographic processing unit 120 encrypts the contract data created according to the coordinated conditions based on the block chain, and stores it in the block chain sector where the goods data is stored, and at the same time stores the data in the seller terminal and the buyer terminal By guiding , it is possible to support the seller's terminal and the buyer's terminal to access the blockchain sector and obtain contract data.

When the contract data is rejected by any one of the seller terminal and the buyer terminal receiving the contract data, the interface unit 110 may receive a reason for rejection from the rejected terminal. That is, when a rejection of contract data occurs from any one terminal even after the condition is adjusted, the interface unit 110 may receive an input of the reason from the corresponding terminal.

After inputting the reason for rejection, the encryption processing unit 120 encrypts the reason for rejection in the block chain method, stores it in the block chain sector, and does not enter the reason for rejection and reason for rejection through the block chain sector It can be provided to a terminal that does not That is, the cryptographic processing unit 120 stores the reason for rejection in the block chain sector in response to the contract data, so that the contract progress process for the goods can be stored as a history.

If, together with the reason for rejection, revision details for contract data are input from any one terminal, the writing unit 130 creates new contract data according to the revision details, encrypts the data based on the block chain, and then the other terminal The above process can be repeated.

On the other hand, when the contract data is approved by both the seller terminal and the buyer terminal receiving the contract data, the cryptographic processing unit 120 may convert the contract data from the final contract data and store it in the block chain sector. That is, as the contract data is confirmed from both terminals, the cryptographic processing unit 120 may determine the contract data as the final contract data, and then store the contract data in the block chain sector in response to the goods data for preservation.

In another embodiment, when the purchase condition is rejected by the seller terminal, the interface unit 110 may receive a reason for rejection from the seller terminal. That is, when the purchase condition input by the purchaser terminal is not accepted by the seller terminal, the interface unit 110 may receive the reason for rejecting the purchase condition from the seller terminal.

Thereafter, the cryptographic processing unit 120 encrypts the reason for rejection in the block chain method, stores it in the block chain sector, and provides the reason for rejection to the purchaser terminal through the block chain sector, so that the purchaser terminal to re-enter the new purchase conditions. That is, the cryptographic processing unit 120 stores the reason for rejection in the block chain sector in response to the purchase condition, thereby keeping the contract progress process for the goods as a history, and also rejecting the purchase condition at the seller terminal, and the block chain to the buyer terminal Based on the notification, it is possible to induce the purchaser terminal to input new purchase conditions (or to reject the contract itself).

In another embodiment, when a transaction interruption is input from the seller terminal, the cryptographic processing unit 120 switches the state mode of the goods data to access prohibition, so that the search for the goods data is not performed by the purchaser terminal. can prevent it That is, the cryptographic processing unit 120 may restrict access/search of the purchaser terminal to the related goods data stored in the block chain sector when a transaction stop is inputted from the seller terminal in order to ensure the transaction interruption by the seller terminal. .

According to an embodiment of the present invention, a method and apparatus for a blockchain-based goods contract service are provided, which register a reliable intermediary using a smart contract operating on the Ethereum blockchain and utilize it in the value verification and contract process of goods. can

In addition, according to an embodiment of the present invention, the reliability of the contract process can be guaranteed by registering the contents of registration of goods, proposals, and contract processes in the block chain.

In addition, according to an embodiment of the present invention, since all operation processes are registered in the smart contract and stored in the transaction history of the Ethereum block chain, the reliability of the registered data can be guaranteed.

In addition, according to an embodiment of the present invention, since the entire process of registration, proposal, and contract is operated by a state machine-based smart contract, the user can more safely control the contract process.

2 is a diagram for explaining the system structure of Trade B according to the present invention.

As shown in Figure 2, the Trade B service requires a distributed application that a user can access and use by deploying a smart contract for the operation of the Trade B service on a blockchain network built using an Ethereum node. The distributed application may receive a user's request, interact with the smart contract through the web3.js module, and store information such as information on goods, purchase proposals, and transaction details. In ① of FIG. 2, the seller can register goods in the smart contract, and in ②, the buyer can access the registered goods and use services such as purchase proposals and contracts.

Trade B can provide reliable goods contract services by registering information about specific goods, purchase proposals, and contracting processes together on the blockchain. For this purpose, the Property contract operates, and in brief, it is shown in [Table 1].

When the first seller applies for goods registration, the goods information is stored only in the database, and when the broker verifies the goods after that, the goods information is registered in the property contract. The basic operation of the Property contract is controlled by PropertyStatus, which is the state variable of individual goods. The state of each good is as follows.

(1) The broker verifies the goods and is registered on the blockchain, but the seller is not approved to start selling.

(2) Onsale status, where the seller authorizes the seller to start selling the goods so that the buyer can inquire about the goods and send a purchase offer.

(3) The status of an Agreement in which the seller accepts one of the purchase offers sent by the buyer and concludes a contract based on the accepted offer with the originator of the offer.

(4) The status of SoldOut where the contract has been concluded and the goods have been traded.

(5) Cancel status in which the buyer's inquiry and transaction are impossible because the seller cancels the registration of the goods.

In addition to the basic information of goods, the Property contract maps and stores purchase proposals and contract details with the sender's account address.

Trade B uses an intermediary by registering an intermediary in a smart contract for goods contracts, unlike existing services that aim for a p2p transaction method on the block chain. Through this, Trade B solves the problems of ambiguity in the value judgment of existing services and the fairness of the contract process through a verified broker. At this time, reliable brokers may be selected by other techniques on the basis of qualifications, experience, reputation, and the like. Broker contract operating for broker registration service registers a broker with a guaranteed identity in the form of a structure along with major fields and the number of successfully concluded contracts, so that sellers and buyers using the service can check it. A broker can verify a specific product and be registered as a broker of the property contract for that product, and can also certify the adequacy of the contract process thereafter.

Trade B provides a service where buyers offer purchase terms for goods in OnSale status. Various buyers can send purchase proposals, and each proposal is stored in the property contract in the form of a structure. The purchase offer is controlled by the flow of individual states.

3 is a diagram for explaining an operation flow of a purchase proposal according to the present invention.

As shown in FIG. 3 , a purchase offer is defined as a state chart, and is divided into the process of (1) to (4) accepting the offer, and the operations of (a) and (b) rejecting the offer.

(1) Buyer creates a pending offer for a specific good in Onsale status.

(2) When the created proposal is sent to the seller, Trade B changes the proposal status to sent.

(3) When the seller receives and confirms the offer, Trade B changes the offer status to review.

(4) If you agree and accept the received proposal, Trade B changes the proposal status to accepted and the status of goods to agreement to enter the contract conclusion phase.

(a) If the received proposal is rejected, Trade B changes the proposal status to rejected.

(b) When the reason for rejection of the offer is sent to the buyer, Trade B changes the offer back to pending status.

If the seller rejects the offer, Trade B stores the reason for rejecting the offer in the offer structure sent by the buyer so that the buyer can check it. Through this, the buyer can change the offer and resend it to the seller, and repeat the offer process until the seller accepts the specific offer and moves on to the contract stage.

When one proposal is accepted according to the process of (1) to (4) of FIG. 3, the state of the goods is changed to agreement, and the seller and the buyer can conclude a contract based on the accepted proposal.

4 and 5 are diagrams for explaining the operation flow of the contract service provided by Trade B according to the present invention.

As shown in Figs. 4 and 5, the contract service is defined as a state chart, with operations (1) to (9) for contract conclusion, and operations (a) to (d) for contract cancellation or goods registration cancellation. is composed

(1) After accepting the offer and changing the status of the goods to agreement, Trade B creates a draft contract based on the offer accepted by the broker and stores the contents in the pending contract structure.

(2) Trade B sends the draft or amendment of the contract created by the broker to the seller and buyer to change the state of the goods to the sent state.

(3) When the draft contract or amendments are confirmed by the seller and buyer, Trade B changes the goods status to review status.

(4) If the seller and buyer agree on the draft or amendment of the contract, Trade B changes the status of the goods to finalForm status, which is the final version of the contract.

(5) If the broker sends the final contract to the seller and the seller confirms, Trade B changes the goods status to sellerReceive status.

(6) When the final contract is approved by the seller and payment is completed, Trade B changes the goods status to sellerSign status.

(7) When the final contract paid by the seller is sent to the buyer and the buyer confirms, Trade B changes the state of the goods to the buyerReceive state.

(8) When the buyer approves the final contract and completes the payment, Trade B changes the goods status to buyerSign status.

(9) When the broker confirms the contract on which the payment of the seller and the buyer has been completed and finally concludes the contract, Trade B changes the state of the goods to the complete state.

(a) If at least one of the seller and the buyer rejects the draft contract prepared by the broker, Trade B changes the status of the goods to rejected.

(b) When the seller and buyer store the reasons for rejecting the draft contract in the contract structure, Trade B returns it to the broker and changes the status of the goods to pending.

(c) If the seller wants to stop selling the goods, Trade B cancels the registration regardless of the state of the goods and changes the state of the goods to the canceled state where the buyer cannot inquire or access.

(d) If the seller and buyer want to cancel the contract, Trade B can cancel the contract regardless of the contract status and change the status of the goods to OnSale, which can receive offers from other buyers.

The operation corresponding to each number in FIGS. 3 to 5 is operated as an internal function of the Property contract, and a modifier provided by Solidity is attached and used for state machine-based operation. A modifier is a function guard that determines whether to proceed to the function code in advance by checking the condition and state before the operation of the function. Through this, Trade B can control the sequential execution of functions by preventing inappropriate behavior that does not fit the state.

Trade B provides services in the form of a web application, consisting of a goods registration screen, a goods list screen showing a list of goods in OnSale status, a proposal screen for purchase proposals, and a contract screen for contract conclusion. When goods are registered on the goods registration screen, goods information is stored in the property contract, and when the registrant approves the sale, the state of the goods is changed to OnSale and output on the goods list screen. For the registered goods, Trade B can generate a purchase offer and send it to the seller, and when the seller accepts the offer, it can proceed to the contracting process. In addition, Trade B uses the web3.js module for communication between the server that provides web services and the blockchain network where smart contracts are deployed. All functions used for function operation refer to the state of goods, proposals, and contracts within the Property contract, so call and use the smart contract instance through the web3.js module.

[Table 2] exemplifies a function related to a purchase proposal.

[Table 2] is an example code of the part where the buyer creates a purchase proposal, and the contract address necessary to call the smart contract instance is firstly returned, and through this, the property contract instance of the corresponding product is called. After that, Trade B creates a proposal by the operation of an internal function and checks the status of the created proposal.

Trade B can be a goods contract service that guarantees the adequacy of goods contracts and prevents forgery/falsification by registering reliable intermediaries, goods information, purchase proposals, and contract details in a smart contract based on the Ethereum blockchain. In Trade B, a registered broker judges the value of goods and can play a pivotal role in the contract conclusion process.

Since the seller and buyer are certified for the value of goods and the appropriateness of the contract by a trusted intermediary registered in the blockchain, Trade B solves the problem of ambiguity in the verification of goods value and the reliability of contracts with existing goods and contract services. can

In addition, Trade B distributes a broker contract that registers a broker, a PropertyFactory contract that creates a property contract when new goods are registered, and a property contract that registers information about specific goods, proposals and contracts on the Ethereum blockchain network for service operation. use. All service functions are defined by state charts, and can be safely controlled according to the state by operating based on the state machine. Through this, when an inappropriate input value is input as an action for the state, Trade B can increase the durability against exceptions by returning an error.

Trade B was developed using the Truffle framework for developing Ethereum distributed applications and web3.js, a java script module to communicate with the blockchain, and deployed on the Ethereum blockchain network composed of Geth (Go-ethereum) nodes. to verify the service function.

It is differentiated from existing goods and contract services by the fact that when a contract is concluded using Trade B, the value of goods and the appropriateness of the contract are guaranteed by the broker, and the status of the contract process can be reliably inquired in real time through the block chain. service can be used.

Hereinafter, a work flow of the block chain-based goods contract service apparatus 100 according to embodiments of the present invention will be described in detail in FIG. 6 .

6 is a flowchart illustrating a blockchain-based goods contract service method according to an embodiment of the present invention.

The blockchain-based goods contract service method according to the present embodiment may be performed by the blockchain-based goods contract service apparatus 100 .

First, as the goods data is input from the seller terminal, the block chain-based goods contract service apparatus 100 transmits the goods data to the broker terminal that satisfies the prescribed conditions (610). Step 610 may be a process of selecting an intermediary for buying and selling goods as data on goods to be sold is received, and delivering the goods to a terminal of the intermediary.

Here, goods have a value and are objects that can be bought and sold at a price, for example, commodities, real estate, etc. may be exemplified.

In selecting an intermediary, the block chain-based goods contract service apparatus 100 may select a specific number of intermediaries that meet the conditions from among intermediary groups specialized in the category of input goods data. The condition may be whether or not you have a license, whether you have a transaction history, whether you have capital/equipment, etc. For example, if the goods data is about 'real estate', the block chain-based goods contract service device 100 is a real estate agent while possessing a licensed real estate agent Brokers with more than '10' brokerage histories can be selected from the broker group to select two or more brokers.

The broker terminal that has received the goods data determines whether or not to authenticate the goods data after determining whether the goods data has a significant enough value to transact, whether the seller who entered the goods data can be trusted, and the like, and the present invention will return to the blockchain-based goods contract service device 100 of

When the goods data is returned as unauthenticated because it does not meet the standards, the block chain-based goods contract service apparatus 100 may notify the seller terminal of the impossibility of intermediary for the goods data.

On the other hand, when the goods data is authenticated by achieving the standard, the block chain-based goods contract service device 100 performs brokerage processing for the goods data based on the blockchain.

In addition, the block chain-based goods contract service apparatus 100 encrypts the goods data returned after being authenticated by the broker terminal in a block chain method and stores it in the block chain sector ( 620 ). Step 620 may be a process of encrypting intermediary good data based on a block chain and registering it on the block chain network, so that the goods data is propagated in an encrypted state on the block chain network.

Subsequently, the block chain-based goods contract service apparatus 100 may connect the buyer terminal searching for the goods data and the seller terminal through the block chain sector ( 630 ). This step 630 may be a process of matching the seller terminal and the buyer terminal as a purchase intention is input in the purchaser terminal that has searched for the goods data on the block chain network.

Through this, the block chain-based goods contract service apparatus 100 may perform mediation processing between the seller terminal and the buyer terminal with respect to the goods data.

In the process of encrypting the goods data input by the seller terminal based on the block chain, the block chain-based goods contract service apparatus 100 may collect broker information about the broker terminal in conjunction with the return of the goods data. That is, the block chain-based goods contract service apparatus 100 may additionally receive information on the broker who brokers the goods data for which the brokerage transaction is possible by being authenticated by the broker terminal.

Thereafter, the block chain-based goods contract service apparatus 100 encrypts the collected broker information together with the goods data and stores it in the block chain sector. That is, the block-chain-based goods contract service apparatus 100 may play a role in encrypting information about an intermediary that is intermediary by authenticating goods data, matching it with the goods data, and storing it in the blockchain sector.

Through this, the block chain-based goods contract service device 100 can improve the reliability of the brokerage transaction by clarifying the middleman who processes the goods data.

In addition, the block chain-based goods contract service apparatus 100 may receive a purchase condition related to the goods data from the purchaser terminal. That is, the block chain-based goods contract service device 100 may search for goods data and receive purchase conditions necessary for purchase from a purchaser willing to purchase.

Here, the purchase condition may be, for example, adjustment of a reduction in the sale price suggested by the seller, adjustment of the lease start time, adjustment of the rental period, etc. when the goods are real estate.

The block chain-based goods contract service device 100 encrypts the purchase condition in the block chain method, stores it in the block chain sector, and provides the purchase condition to the seller terminal through the block chain sector. , it is possible to determine whether to accept the purchase condition by the seller terminal. That is, the block chain-based goods contract service device 100 transmits the purchase condition of the buyer to the seller based on the block chain, so that the seller can determine whether to accept the purchase condition.

Thereafter, the seller terminal may determine whether to accept the purchase condition registered by the purchaser terminal, and then input it to the block chain-based goods contract service apparatus 100 .

As a result, the block chain-based goods contract service device 100 can perform an intermediary process that adjusts/coordinates the conditions for purchase through the goods data between the connected seller terminal and the buyer terminal based on the block chain. there is.

After the condition adjustment is made, the block chain-based goods contract service device 100 creates contract data regarding the goods data in which the purchase conditions are accepted by the seller terminal. That is, the block-chain-based goods contract service device 100 may serve to write contract data by writing the content of the purchase and sale contract related to the goods in accordance with a prescribed abbreviation.

Here, the contract data may include, for example, information on the goods to be sold (location, size, use, etc.), information on the adjusted sale amount (including down payment), and a transfer schedule of the amount delivered to the seller.

After writing the contract data, the block chain-based goods contract service device 100 encrypts the contract data in the block chain method and stores it in the block chain sector, and connects the contract data through the block chain sector It is provided to the buyer terminal and the seller terminal. That is, the block chain-based goods contract service device 100 encrypts the contract data created according to the coordinated conditions based on the block chain, and stores it in the block chain sector where the goods data is stored, and at the same time, with the seller terminal By notifying the purchaser terminal of the storage fact, it is possible to support the seller terminal and the purchaser terminal to access the block chain sector and obtain contract data.

When the contract data is rejected by any one of the seller terminal and the buyer terminal receiving the contract data, the block chain-based goods contract service apparatus 100 may receive a reason for rejection from the rejected terminal . That is, the block chain-based goods contract service apparatus 100 may receive a reason from the corresponding terminal when rejection of contract data occurs from any one terminal even after the condition is adjusted.

After inputting the reason for rejection, the block chain-based goods contract service device 100 encrypts the reason for rejection in the block chain method, stores it in the block chain sector, and provides the reason for rejection through the block chain sector, It can be provided to a terminal that does not input a reason for rejection. That is, the block chain-based goods contract service device 100 stores the reason for rejection in the block chain sector in response to the contract data, so that the contract progress process for the goods can be stored as a history.

If, together with the reason for rejection, revision details for contract data are input from any one terminal, the block chain-based goods contract service device 100 creates new contract data according to the revision details and uses the block chain based After encryption, the above-described process of providing to the opposite terminal may be repeated.

On the other hand, when the contract data is approved from both the seller terminal and the buyer terminal receiving the contract data, the block chain-based goods contract service device 100 converts the contract data from the final contract data, and the block chain sector can be stored in That is, the block chain-based goods contract service device 100 confirms the contract data as final contract data as the contract data from both terminals is confirmed, and then stores the contract data in the block chain sector in response to the goods data for preservation. can

In another embodiment, when the purchase condition is rejected by the seller terminal, the block chain-based goods contract service apparatus 100 may receive a reason for rejection from the seller terminal. That is, when the purchase condition input by the purchaser terminal is not accepted by the seller terminal, the block chain-based goods contract service apparatus 100 may receive the reason for rejecting the purchase condition from the seller terminal.

Thereafter, the block chain-based goods contract service apparatus 100 encrypts the reason for rejection in the block chain method, stores it in the block chain sector, and provides the reason for rejection to the purchaser terminal through the block chain sector By doing so, it is possible to re-enter a new purchase condition in the purchaser terminal. That is, the block chain-based goods contract service device 100 stores the reason for rejection in the block chain sector in response to the purchase conditions, so as to keep the contract progress for the goods as a history, and also to reject the purchase conditions at the seller terminal, By notifying the purchaser terminal based on blockchain, the purchaser terminal can induce input of new purchase conditions (or rejection of the contract itself).

In another embodiment, when a transaction interruption is input from the seller terminal, the block chain-based goods contract service device 100 switches the state mode of the goods data to access prohibited, and the goods data by the purchaser terminal can be prevented from being searched for. That is, the block chain-based goods contract service apparatus 100 provides access/search of the purchaser terminal to the related goods data stored in the block chain sector when a transaction stop is inputted from the seller terminal in order to ensure the transaction interruption by the seller terminal. can be limited.

According to an embodiment of the present invention, a method and apparatus for a blockchain-based goods contract service, which registers a reliable broker using a smart contract operating on the Ethereum blockchain, and is used in the value verification and contract process of goods, are provided. can

In addition, according to an embodiment of the present invention, the reliability of the contract process can be guaranteed by registering the contents of registration of goods, proposals, and contract processes in the block chain.

In addition, according to an embodiment of the present invention, since all operation processes are registered in the smart contract and stored in the transaction history of the Ethereum blockchain, the reliability of the registered data can be guaranteed.

In addition, according to an embodiment of the present invention, since the entire process of registration, proposal, and contract is operated by a state machine-based smart contract, the user can more safely control the contract process.

The method according to the embodiment may be implemented in the form of program instructions that can be executed through various computer means and recorded in a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, etc. alone or in combination. The program instructions recorded on the medium may be specially designed and configured for the embodiment, or may be known and available to those skilled in the art of computer software. Examples of the computer-readable recording medium include magnetic media such as hard disks, floppy disks and magnetic tapes, optical media such as CD-ROMs and DVDs, and magnetic media such as floppy disks. - includes magneto-optical media, and hardware devices specially configured to store and execute program instructions, such as ROM, RAM, flash memory, and the like. Examples of program instructions include not only machine language codes such as those generated by a compiler, but also high-level language codes that can be executed by a computer using an interpreter or the like. The hardware devices described above may be configured to operate as one or more software modules to perform the operations of the embodiments, and vice versa.

Software may comprise a computer program, code, instructions, or a combination of one or more thereof, which configures a processing device to operate as desired or is independently or collectively processed You can command the device. The software and/or data may be any kind of machine, component, physical device, virtual equipment, computer storage medium or apparatus, to be interpreted by or to provide instructions or data to the processing device. , or may be permanently or temporarily embody in a transmitted signal wave. The software may be distributed over networked computer systems and stored or executed in a distributed manner. Software and data may be stored in one or more computer-readable recording media.

As described above, although the embodiments have been described with reference to the limited drawings, those skilled in the art may apply various technical modifications and variations based on the above. For example, the described techniques are performed in an order different from the described method, and/or the described components of the system, structure, apparatus, circuit, etc. are combined or combined in a different form than the described method, or other components Or substituted or substituted by equivalents may achieve an appropriate result.

Therefore, other implementations, other embodiments, and equivalents to the claims are also within the scope of the following claims.

100: Blockchain-based goods contract service device
110: interface unit 120: encryption processing unit
130: writing unit

Claims (16)

In the blockchain-based goods contract service method implemented by the blockchain-based goods contract service device,
In the interface unit in the block chain-based goods contract service device, as the goods data is input from the seller terminal, transferring the goods data to the broker terminal that satisfies a prescribed condition;
Encrypting, in the cryptographic processing unit in the block chain-based goods contract service device, the goods data returned after being authenticated by the intermediary terminal, in a block chain method and storing it in a block chain sector;
connecting, in the cryptographic processing unit, a buyer terminal searching for the goods data and the seller terminal through the block chain sector;
receiving, in the interface unit, a purchase condition related to the goods data from the purchaser terminal;
encrypting, in the encryption processing unit, the purchase condition in the block chain method and storing the purchase condition in the block chain sector;
determining, in the cryptographic processing unit, whether to accept the purchase condition by the seller terminal by providing the purchase condition to the seller terminal through the block chain sector;
receiving, in the interface unit, a first reason for rejection from the seller terminal when the purchase condition is rejected by the seller terminal;
encrypting, in the encryption processing unit, the first rejection reason in the block chain method and storing the first rejection reason in the block chain sector;
by providing, in the cryptographic processing unit, the first rejection reason to the purchaser terminal through the block chain sector, to re-enter a new purchase condition in the purchaser terminal;
writing contract data related to the goods data in which the purchase conditions are accepted by the seller terminal in the creation unit in the block chain-based goods contract service device;
encrypting, in the encryption processing unit, the contract data in the block chain method and storing the contract data in a block chain sector;
providing, in the cryptographic processing unit, the contract data to the connected purchaser terminal and the seller terminal through the block chain sector;
When the contract data is rejected by any one of the seller terminal and the buyer terminal,
receiving, in the interface unit, a second reason for rejection and revision details for the contract data from the rejected terminal;
In the encryption processing unit, the second rejection reason is encrypted by the block chain method and stored in the block chain sector, and contract data is newly created according to the modification details, encrypted based on block chain and stored in the block chain sector to do; and
Providing, in the cryptographic processing unit, the second reason for rejection and the newly created contract data to a terminal that has not been rejected through the block chain sector
A blockchain-based goods contract service method comprising a. According to claim 1,
collecting, in the interface unit, broker information about the broker terminal in association with the return of the goods data; and
Encrypting, in the encryption processing unit, the collected broker information together with the goods data and storing it in the block chain sector;
A blockchain-based goods contract service method further comprising a. delete delete delete According to claim 1,
When the contract data is approved from both the seller terminal and the buyer terminal,
converting, in the cryptographic processing unit, the contract data from the final contract data, and storing it in the block chain sector;
A blockchain-based goods contract service method further comprising a. delete According to claim 1,
When a transaction stop is input from the seller terminal,
converting, in the encryption processing unit, the state mode of the goods data to access prohibition, so that the purchaser terminal does not search for the goods data
A blockchain-based goods contract service method further comprising a. an interface unit that transmits the goods data to an intermediary terminal that satisfies a prescribed condition as the goods data is input from the seller terminal, and receives a purchase condition for the goods data from the buyer terminal;
The goods data returned after being authenticated by the intermediary terminal are encrypted in a block chain manner and stored in a block chain sector, and the buyer terminal that retrieves the goods data is connected to the seller terminal through the block chain sector, Whether the purchase condition is accepted by the seller terminal by encrypting the purchase condition in the block chain method, storing it in the block chain sector, and providing the purchase condition to the seller terminal through the block chain sector When the purchase condition is rejected by the seller terminal, the first rejection reason input from the seller terminal by the interface unit is encrypted in the block chain method and stored in the block chain sector, an encryption processing unit for re-entering a new purchase condition in the purchaser terminal by providing the first rejection reason to the purchaser terminal through a block chain sector; and
A writing unit that creates contract data related to the goods data for which the purchase condition is accepted by the seller terminal
including,
The encryption processing unit,
The contract data is encrypted by the block chain method and stored in a block chain sector, and the contract data is provided to the connected buyer terminal and the seller terminal through the block chain sector,
When the contract data is rejected by any one of the seller terminal and the buyer terminal,
The interface unit,
receiving a second rejection reason from the rejected terminal;
The encryption processing unit,
The second reason for rejection is encrypted by the block chain method and stored in the block chain sector, new contract data is created according to the revision history, encrypted based on block chain and stored in the block chain sector, and the block chain sector to provide the second reason for rejection and the newly created contract data to the terminal that did not reject
Blockchain-based goods contract service device. 10. The method of claim 9,
The interface unit,
In conjunction with the return of the goods data, the broker information about the broker terminal is collected,
The encryption processing unit,
Encrypting the collected broker information together with the goods data and storing it in the block chain sector
Blockchain-based goods contract service device. delete delete delete 10. The method of claim 9,
When the contract data is approved from both the seller terminal and the buyer terminal,
The encryption processing unit,
Converting the contract data from the final contract data and storing it in the block chain sector
Blockchain-based goods contract service device. delete 10. The method of claim 9,
When a transaction stop is input from the seller terminal,
The encryption processing unit,
By switching the state mode of the goods data to access prohibited, the search for the goods data by the purchaser terminal is not made
Blockchain-based goods contract service device.

Images