KR20200080462A - System for token transaction based on block chain - Google Patents

Abstract

The present invention relates to a blockchain-based token transaction system. More specifically, the present invention, in which when a user terminal subscribes to a token management server and requests token issuance for a specific project conducted by a seller terminal, the token management server transmits a transaction to the seller terminal to issue tokens and overall management of the specific project is conducted by the seller terminal.

Description

Blockchain-based token trading system{SYSTEM FOR TOKEN TRANSACTION BASED ON BLOCK CHAIN}

The present invention relates to a blockchain-based token transaction system, and more specifically, when a user terminal subscribes to a token management server and requests to issue a token of a specific project that the seller terminal proceeds, the token management server makes a transaction to the seller terminal. It is related to a blockchain-based token transaction system that allows transmission and issuance of tokens and overall management of a specific project conducted by the seller terminal.

Ethereum, proposed by Vitalik Buterin, can easily implement smart contracts in code and is completely Turing. Ethereum proposed by Vitalik Buterin was proposed to overcome the Turing imperfections of the Bitcoin scripting language used in escrow contracts in Bitcoin transactions. Bitcoin's transaction is only used to change the balance item of the account, and the script language used in the transaction is only used limitedly, such as an escrow contract. Ethereum expands the status of this account to balance, as well as data and code, and executes a series of code recorded in the account through transactions, making the state conversion condition of the account close to Turing complete, which is a large-scale distributed application ( Decentralized Application (DApp) was provided as an easy tool for production. Accordingly, decentralized applications (DApps) using the Ethereum blockchain are actively being developed as smart contracts that can be easily implemented.

ICO (Initial Coin Offering), a form in which distributed application projects receive a crowd funding by issuing coins to raise initial funds, has been widely used. As the ICO has been widely implemented, investments have been made with the anonymity of the blockchain, and there is no legal protection, so it has been banned in major countries such as the United States and China.

Therefore, as in general financial transactions, there is a need for a system that can verify the identity of the person who is trading or investing and prevent the ICO from being abused.

Document 1: Registration Patent 10-1914576, Registration Date October 29, 2018, "Compensation System for Reducing Carbon Emissions Using Cryptocurrency" Document 2: Registered Patent 10-1878869, Registration Date July 10, 2018, "Distributed Ledger Device and Distributed Ledger Method for User Identification Management Based on Blockchain"

The present invention was created to solve such a problem, and the object of the present invention is that the token management server transacts to the seller terminal when the user terminal joins the token management server and requests the issuance of a token of a specific project that the seller terminal proceeds. It is to provide a token trading system based on a blockchain that transmits a token to issue a token and manages a specific project that the seller terminal progresses in general.

The blockchain-based token transaction system according to the present invention for achieving the above object is a user terminal 100 that requests token issuance of a specific project after user authentication through membership registration or login to the token management server 200 ; A token management server 200 for requesting a transaction to issue a token used for the project requested from the user terminal 100 to the seller terminal 300; And when the transaction is received from the token management server 200, the structure of the transaction is checked through the Ethereum state conversion function based on the blockchain, and the error is not returned and the token is only processed when user identification authentication is successful. It characterized in that it comprises a seller terminal 300 issued and provided to the user terminal 100.

According to a preferred embodiment of the present invention, when the user terminal 100 registers as a member to the token management server 200, log-in information, Ethereum address, email, user name and date of birth in the token management server 200 It is characterized by transmitting.

According to a preferred embodiment of the present invention, the token management server 200 receives login information, Ethereum address, email, user name and date of birth from the user terminal 100 when the user terminal 100 is registered as a member. Characterized in that the received and stored.

According to a preferred embodiment of the present invention, the transaction requested by the token management server 200 to the seller terminal 300 includes the token issuance amount and the user's Ethereum address as much as the balance size capable of identifying the requested project. It is characterized by.

According to a preferred embodiment of the present invention, the token management server 200 occurs when the seller terminal 300 issues a token to the user terminal 100 as much as the token issuance amount requested by the user terminal 100 It is characterized by collecting fees.

According to a preferred embodiment of the present invention, the token management server 200, when the hard cap (HARD CARP) of a specific project that the seller terminal 300 proceeds is achieved, even if the project period remains, the project is closed, It is characterized in that the coin of a specific project carried out by the seller terminal 300 is listed on the cryptocurrency exchange.

According to a preferred embodiment of the present invention, the token management server 200, if a specific project that the seller terminal 300 proceeds does not achieve a soft cap (SOFT CAP) during the project period, the seller terminal 300 It is characterized in that it controls to repay all of the investment ether acquired by issuing a token to the user terminal 100 to the user terminal 100.

According to a preferred embodiment of the present invention, the token management server 200 does not achieve a soft cap (SOFT CAP) for a specific project that the seller terminal 300 proceeds during the project period, but the user terminal invested in the project When the number of (100) exceeds a preset number, it is characterized in that the coin of a specific project carried out by the seller terminal 300 is listed on the virtual currency exchange.

According to a preferred embodiment of the present invention, the token management server 200 is configured to issue tokens before the project period ends after the user terminal 100 receives tokens of a specific project that the seller terminal 300 proceeds. When requesting the return of the invested investment ether, it is characterized in that the seller terminal 300 controls to repay only a certain amount of the investment ether for the token to the user terminal 100.

In the blockchain-based token transaction system according to the present invention, when the user terminal joins the token management server and requests the issuance of a token of a specific project conducted by the seller terminal, the token management server sends a transaction to the seller terminal to issue the token This has the effect of confirming the identity of the investor.

In addition, the token management server has the effect of preventing the seller terminal from exploiting it after the completion of the specific project by managing the overall project of the seller terminal.

1 is a block diagram of a token transaction system according to an embodiment of the present invention
Figure 2 is a token transaction flow chart through a token transaction system according to an embodiment of the present invention
Figure 3 is a specific project management embodiment of the token management server according to an embodiment of the present invention Figure 1
Figure 4 is a specific project management example 2 of the token management server according to an embodiment of the present invention
Figure 5 is a specific project management embodiment of the token management server according to an embodiment of the present invention Figure 3

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art to which the present invention pertains may easily practice. However, the present invention can be configured in many different forms and is not limited to the embodiments described herein. In addition, in order to describe the present invention in the drawings, parts irrelevant to the description are omitted, and like reference numerals are assigned to similar parts throughout the specification.

Throughout the specification, when a part is “connected” to another part, it is not only “directly connected”, but also a part that is “indirectly connected” through another part. When "included", this means that other components may be included, not excluded, unless otherwise stated.

Prior to the description of the present invention, the Ethereum address, message and transaction, and contract (Ethereum state conversion function) will be described first to help understanding Ethereum.

When we first describe the Ethereum address, the state in Ethereum consists of objects called accounts. Each account has an Ethereum balance, a 20-byte address, and a state conversion code that delivers data and information directly. The specific items are as follows.

(1) nonce: a counter that allows individual transactions to be processed only once

(2) The current ether balance of the account

(3) Account contract code (optional)

(4) Account storage space (initially empty)

Ethereum is a cryptocurrency based on the same principle as Bitcoin and is used to pay transaction fees. There are two types of accounts: Externally Owned Accounts controlled by the private key and Contract Accounts controlled by the contract code.

Externally owned accounts do not have code, and to send messages from this account, they create a new transaction and sign it, which is the same as Bitcoin. Each time a contract account receives a message, it activates its code and reads the message or writes it to the internal storage space, sends other messages or creates a contract in turn. In Ethereum, contracts can be identified as actonomous agents that exist within Ethereum's execution environment, and are recorded in the contract's balance and blockchain to directly control its key value store for tracking variables.

Next, when describing messages and transactions, the term transaction used in Ethereum refers to data that an externally owned account creates and signs a message to send to the network. The transaction includes the following items.

(1) Message destination

(2) Signature to verify the sender

(3) The amount of ether sent from the sender to the receiver

(4) Data field (optional)

(5) STARTGAS, the maximum calculation step allowed for a transaction

(6) GASPRICE, fee paid by the sender at every step

The first three items are the values used almost as standard in cryptocurrency. Although the initial function is not defined in the data field, the virtual machine has the code to use when the contract accesses the data field.

For example, if there is a contract with a domain registration service function on the blockchain, the data sent to this contract can be interpreted as having one key-value pair. The key is the domain you want to register, and the value is the IP address. The contract reads these values from the message data and stores them in the repository. The STARTGAS and GASPRICE fields play an important role in preventing Ethereum's denial of service attacks.

In order to prevent malicious infinite loops or excessive calculations within the code, individual transactions limit the number of codes. The unit of calculation is gas, and one step is required at the cost of 1 gas and must be stored. If the amount of data is large, a larger gas cost is required. In addition, a fee of 5gas per byte is required to execute transaction data. The intention of this fee system is to prevent an attacker from attacking by forcing an attacker to pay a fee in proportion to all resources consumed by the attacker, including calculation, bandwidth, storage, and so on.

Finally, when describing the contract (the Ethereum state conversion function), the following conditions must be satisfied in order for a transaction to be included in a block within Ethereum. Here, gas is a unit of fee that Ethereum transaction pays to be included in the block. 1gas is 1/(10^18) Ethereum. The Ethereum state conversion function performs the following tasks.

(1) Check the structure of the transaction, and verify that the signature is valid and whether the delivered nonce matches the sender's nonce. If they do not match, an error is returned.

(2) Calculate the transaction fee with STARTGAS * GASPRICE, and determine the source address from the signature. Subtract the commission from the sender's account balance and increase the sender nonce value. If the balance is insufficient, an error is returned.

(3) After initializing with GAS = STARTGAS, gas is subtracted in proportion to the bytes included.

Sends a transaction from the sending account to the receiving account, changes the status of the receiving account, and if the receiving account is a contract, the transaction is executed until the contract no longer appears or the gas is exhausted. If the Ethereum of the sender is insufficient, the transfer of funds will fail, or if all the gas is consumed in the code execution process, all the status changes will be returned to the original state. However, fees already paid are excluded and added to the miner's account. The fee for the remaining gas is returned to the sender, and the spent gas and the fee paid are sent to the miner. If there is insufficient gas at the time of executing the message, all state changes related to the message are restored, but the parent execution does not need to be returned. This means that the contract has no problems in calling other contracts. If account A has gas G and calls account B, the execution of account A consumes up to G gas.

Hereinafter, a blockchain-based token transaction system according to the present invention utilizing Ethereum as described above will be described in detail through drawings.

1 is a block diagram of a token transaction system according to an embodiment of the present invention. As shown in Figure 1, the token transaction system according to the present invention is a user terminal 100 and the user terminal requesting token issuance of a specific project after user authentication through membership registration or login to the token management server 200 When receiving the transaction from the token management server 200 and the token management server 200 requesting the seller terminal 300 for a transaction for issuing a token used for the project requested from (100), to the blockchain Including the merchant terminal 300 that provides the token to the user terminal 100 by issuing a token only when the user identification authentication is successful by checking the structure of the transaction through the Ethereum-based state conversion function and not returning an error. It is composed.

The user terminal 100 is a terminal used by a person who wants to participate in a project, and includes a smart phone, a desktop PC, a tablet PC, a slate PC, and a notebook computer. computer). Of course, the present invention is not limited to this, and any terminal capable of communicating with an external device may be used.

The specific project in which the user terminal 100 requests the issuance of tokens means a form in which distributed application projects receive crowdfunding by issuing coins, that is, an ICO (Initial Coin Offering) project.

The token management server 200 requests a transaction for issuing a token used for the project requested from the user terminal 100 to the seller terminal 300, and the transaction includes a signature to verify the message destination and originator, and a destination. It may include the amount of investment ether sent from the destination to the destination, the data field (optional), the maximum calculation step allowed for the transaction, STARTGAS, and GASPRICE, the fee paid by the sender at each step.

The seller terminal 300 is a terminal used by a person who is carrying out a specific project, a smart phone, a desktop PC, a tablet PC, a slate PC, a notebook computer computer). Of course, the present invention is not limited to this, and any terminal capable of communicating with an external device may be used.

2 is a flow chart of a token transaction through a token transaction system according to an embodiment of the present invention. As shown in FIG. 2, the token transaction method through the token transaction system according to the present invention includes a token issuance request process (S100), a transaction request process (S200), and a token issuance process (S300).

The token issuance request process (S100) is a process in which the user terminal 100 requests the issuance of a token for a specific project after user authentication through membership registration or login to the token management server 200. To this end, the use terminal 100 provides a user interface (UI) through which the user can practically input information and requests.

At this time, the user terminal 100 is authenticated by entering information to identify a user such as login information, Ethereum address, email address, user name, and date of birth when registering for membership, and the authenticated information is token management server After transmitting to (200) to complete the membership registration, the token management server 200 requests to issue a token of a specific project.

The transaction request process (S200) is a process in which the token management server 200 requests a transaction for issuing a token used in the requested project from the user terminal 100 to the seller terminal 300. The transaction includes the amount of token issuance and the user's Ethereum address as much as the balance size to identify the requested project.

At this time, the token management server 200 securely stores the information of the user who is registered as a member when the user terminal 100 registers for membership. That is, it stores the login information received from the user terminal 100, the user's Ethereum address, email address, user name and date of birth.

In the token issuing process (S300), when the seller terminal 300 receives the transaction from the token management server 200, an error is returned by checking the structure of the transaction through an Ethereum state conversion function based on blockchain. It is a process of issuing a token and providing it to the user terminal 100 only when the user identification authentication is successful.

That is, the user terminal 100 through the process of registering a member to the token management server 200 and the seller terminal 300 through the process of checking the structure of the transaction through the Ethereum status conversion function of the user terminal 100 You can confirm your identity.

In addition, the token management server 200 collects a fee incurred when the token is issued to the user terminal 100 as much as the token issuance amount requested by the seller terminal 300 to the user terminal 100 in step S300. do.

In the case of a specific project conducted by the seller terminal 300, that is, in the case of an ICO project, the terms hard cap (soft cap) and soft cap (soft cap) are used. The hard cap means that the seller terminal 300 is an ICO project. In the meantime, it means that the maximum amount that the investment terminal 100 will receive from the user terminal 100 is set, and the soft cap means that the seller terminal 300 proceeds with the ICO project and receives the investment ether from the user terminal 100. It means that you have set a minimum amount for the investment.

However, in the conventional case, there is a problem in that there is a case in which an ICO project that only takes investment ether without listing coins on the cryptocurrency exchange may be exploited even if a soft cap or hard cap is achieved by investing investment ether from an investor through an ICO project.

In the present invention, in order to solve this problem, the token management server 200 manages the ICO project in general.

Figure 3 is a specific project management example 1 of the token management server according to an embodiment of the present invention. As shown in FIG. 3, the seller terminal 300 proceeds with a specific project for a certain period to collect investment ether from the user terminal 100 and issues tokens to the user terminal 100. (S400) At this time, when starting a specific project, a predetermined hard cap may be achieved within a period (S500). In this case, the token management server 200 closes a specific project that the seller terminal 300 proceeds, Coins of a specific project conducted by the seller terminal 300 are listed on the cryptocurrency exchange. (S600)

4 is a specific project management example 2 of the token management server according to an embodiment of the present invention. As shown in FIG. 4, the seller terminal 300 proceeds with a specific project for a certain period to collect investment ether from the user terminal 100 and issues a token to the user terminal 100. (S700) At this time, when a specific project is started, a predetermined period may end (S800). The token management server 200 checks whether a soft cap is achieved in this case, and when the soft cap is not achieved, the seller terminal 300 ) Is issued to issue the token to the user terminal 100, and controls to repay all of the investment ether acquired by the user terminal 100. (S900)

In the process (S900), if the token management server 200 has not achieved a soft cap, but the number of user terminals 100 invested in the project exceeds a preset number, the seller terminal 300 Coins of a specific project conducted by the company are listed on the cryptocurrency exchange.

In addition, in the process (S400, S700), the user terminal 100 requests the return of the investment ether invested in the token issuance before the end of the project period after receiving the token of the specific project proceeded by the seller terminal 300 , It is controlled so that the seller terminal 300 repays only a certain amount of the investment ether for the token to the user terminal 100.

Therefore, as described above, the blockchain-based token trading system according to the present invention has the effect of being able to reliably confirm the identity of the investor and prevent the person who is conducting the ICO project from exploiting the ICO project.

The present invention has been described with reference to the embodiment(s) shown in the drawings, but this is merely exemplary, and those skilled in the art can make various modifications therefrom, and the above-described embodiment ( It will be understood that all or part of the (s) may be configured by selectively combining. Therefore, the true technical protection scope of the present invention should be determined by the technical spirit of the appended claims.

100: user terminal
200: token management server
300: seller terminal

Claims (9)

In a blockchain-based token trading system,
A user terminal 100 that requests token issuance of a specific project after user authentication through membership registration or login to the token management server 200;
A token management server 200 for requesting a transaction to issue a token used for the project requested from the user terminal 100 to the seller terminal 300; And
When the transaction is received from the token management server 200, the structure of the transaction is checked through the Ethereum state conversion function based on the blockchain, and an error is not returned and the token is issued only when user identification authentication is successful Blockchain-based token transaction system, characterized in that it comprises;; the seller terminal 300 to provide to the user terminal 100. According to claim 1, When the user terminal 100 is a member to the token management server 200, the login information, Ethereum address, email, user name and date of birth to the token management server 200 It is a blockchain-based token trading system. 3. The token management server (200) according to claim 2, wherein the token management server (200) receives and stores login information, Ethereum address, email, user name, and date of birth from the user terminal (100) when the user terminal (100) registers for membership. Blockchain-based token transaction system, characterized in that. The method of claim 1, wherein the transaction requested by the token management server (200) to the seller terminal (300) is characterized by including the token issuance amount and the user's Ethereum address as much as the balance size capable of identifying the requested project. Blockchain based token trading system. The method of claim 1, wherein the token management server (200) collects fees incurred when the seller terminal (300) issues tokens to the user terminal (100) as much as the amount of tokens requested by the user terminal (100). Blockchain-based token transaction system, characterized in that. The method of claim 1, wherein the token management server 200, if the hard cap (HARD CARP) of a specific project that the seller terminal 300 proceeds is achieved, the project is closed even if the project period remains, and the seller terminal Blockchain-based token trading system characterized by listing the coins of a specific project proceeded by (300) on a cryptocurrency exchange. According to claim 1, The token management server 200, If the specific project that the seller terminal 300 proceeds to achieve a soft cap (SOFT CAP) during the project period, the seller terminal 300 is a user Blockchain-based token transaction system characterized by controlling to redeem all the investment ether acquired while issuing tokens to the terminal (100) to the user terminal (100). According to claim 1, The token management server 200, the user terminal 100 invested in the project, although the specific project that the seller terminal 300 has not achieved a soft cap (SOFT CAP) during the project period Blockchain-based token trading system, characterized in that when the number of the number exceeds a preset number, the coin of a specific project carried out by the seller terminal 300 is listed on a virtual currency exchange. The investment according to claim 1, wherein the token management server (200) invests in token issuance before the project period ends after the user terminal (100) receives tokens of a specific project that the seller terminal (300) proceeds with. When requesting the return of Ether, the blockchain-based token transaction system characterized in that the seller terminal (300) controls to repay only a certain amount of investment ether for the token to the user terminal (100).

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