KR20190084620A - Financial transaction processing system using doubleness coin - Google Patents

Abstract

According to one technical aspect of the present invention, the financial transaction processing system using dual coins comprises: a master coin exchange server which is located in a master coin exchange managing master coins for transaction between countries and, when a financial transaction processing message is received from a branch coin exchange server located at a branch coin exchange of a certain country among a plurality of countries or from a user terminal, processes a financial transaction by using the master coins according to the type of the financial transaction processing message; and a plurality of branch coin exchange servers which are located in a branch coin exchange managing branch coins of a corresponding country for each of a plurality of countries and, when a financial processing request message using the branch coins is received from the user terminal, processes a financial transaction by interworking with the master coin exchange server according to the type of the financial transaction processing request message or processes a financial transaction by using the branch coins therein. With master coins, which are a base of international financial transactions, the present invention can convert the master coins into different types of virtual currency or support overseas remittance and settlement.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a financial transaction processing system using a double coin,

The present invention relates to a financial transaction processing system using a double coin.

When there was no currency, they exchanged money, and over time coins and bills were created. As technology became more advanced and digitized, new currency concepts such as virtual money appeared. This virtual currency is literally money that does not exist in a virtual environment, unlike real money (coin, paper money) that you actually deal with.

There are about 700 types of these virtual currencies. There are 'Bit Coin', which was first developed in 2008, and virtualization closures that are being actively traded are 'Etherium', 'Ripple', 'Dash', 'Light Coin 'And' Nem '. Virtual coins excluding bit coins are also called alt coins.

Credit cards and various kinds of simple settlement can be used to buy and sell goods with virtual money without cash though virtual money can be bought and sold only by virtual money.

The transactions of these virtual currencies are operated in virtual currency exchanges such as 'Covert', 'Bitsum' and 'Coin One' in Korea. The transaction currency exchange system consists of a system for purchasing a desired virtual currency by depositing the amount corresponding to the user's virtual account, and storing the virtual currency in the electronic wallet and enabling the transaction.

However, most virtual currencies are traded only on virtual currency exchanges and are rarely used for commercial purposes. Coins such as 'Etherium' and 'Nem' actively provide platform support for smart contracts, but the platform is still very abstract and complex, making it difficult to apply it to general business.

In addition, unlike the nominal currency of the system, these virtual currencies have a problem in that the value of money can be lost due to devaluation of the currency, decrease in the number of users, sanctions on the government level, and the possibility of loss due to the lack of stable profit base is high.

It is an object of the present invention to provide a financial transaction processing system using dual coins which can be utilized both for domestic and international currency as well as for commercial use.

It is another object of the present invention to provide a financial transaction processing system using a double coin, which can switch to another kind of virtual currency using a master coin that is the basis of international financial transactions, or to support overseas remittance and overseas settlement do.

It is another object of the present invention to provide a financial transaction processing system using a double coin which enables a financial transaction to be processed in a corresponding country by using a branch coin serving as a local currency of a corresponding country.

In addition, the present invention allows a master coin exchange and a branch coin exchange to operate mutually independently and exclusively, thereby enabling a mutual transaction with another virtual currency using a master coin, and a branch coin to be used only in a corresponding country And to provide a financial transaction processing system using the same.

The above objects and various advantages of the present invention will become more apparent from the preferred embodiments of the present invention by those skilled in the art.

Among the embodiments, the financial transaction processing system using the double coin is located in the master coin exchange managing the master coin for the transactions between the countries, and is provided from a branch coin exchange server located in a branch coin exchange of a specific country among a plurality of countries, A master coin exchange server for processing a financial transaction using the master coin according to the kind of the financial transaction processing message and a branch server for managing a branch coin of a corresponding country for each of a plurality of countries, The method comprising: receiving a financial transaction request message using a branch coin from a user terminal; processing a financial transaction in cooperation with the master coin exchange server according to a type of the financial transaction processing request message; Use And a plurality of branch coin exchange servers for processing financial transactions.

The solution of the above-mentioned problems does not list all the features of the present invention. Various means for solving the problems of the present invention can be understood in detail with reference to specific embodiments of the following detailed description.

According to an embodiment of the present invention, there is an advantage that it can be utilized not only as a currency as a domestic currency but also as a commercial currency.

Further, according to one embodiment of the present invention, there is an advantage that a master coin which is a basis of international financial transactions can be used to switch to another kind of virtual currency, or to support overseas remittance and overseas settlement.

According to an embodiment of the present invention, it is possible to process a financial transaction in a corresponding country by using a branch coin serving as a local currency of a corresponding country.

According to an embodiment of the present invention, master coin exchanges and branch coin exchanges are operated independently and exclusively mutually so that mutual transactions can be made with other virtual coin using a master coin, and branch coin can be used only in a corresponding country .

FIG. 1 is a network diagram illustrating a financial transaction processing system using a dual coin according to an embodiment of the present invention. Referring to FIG.
2 is an exemplary diagram illustrating a data structure of a master coin block according to an embodiment of the present invention.
3 to 5 are diagrams for explaining a data structure of a transaction of a master coin according to an embodiment of the present invention.
6 is an exemplary diagram illustrating a data structure of a wallet of a master coin according to an embodiment of the present invention.
7 is an exemplary diagram illustrating a data structure of a branch coin according to an embodiment of the present invention.
8 to 10 are diagrams for explaining a data structure of a transaction of a branch coin according to an embodiment of the present invention.
11 is an exemplary view for explaining a data structure of a purse of a branch coin according to an embodiment of the present invention.
12 is a view for explaining a country code of a branch coin according to an embodiment of the present invention.
13 is a flowchart illustrating a process of generating a wallet address of a master coin according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

However, the embodiments of the present invention can be modified into various other forms, and the scope of the present invention is not limited to the embodiments described below. Further, the embodiments of the present invention are provided to more fully explain the present invention to those skilled in the art.

The meaning of the terms described in the present invention should be understood as follows.

It should be understood that the singular " include "or" have "are to be construed as including a stated feature, number, step, operation, component, It is to be understood that the combination is intended to specify that it does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

The present invention can be embodied as computer-readable code on a computer-readable recording medium, and the computer-readable recording medium includes all kinds of recording devices for storing data that can be read by a computer system . Examples of the computer-readable recording medium include a ROM, a RAM, a CD-ROM, a magnetic tape, a floppy disk, an optical data storage device, and the like, and a program structure (for example, Application of the < / RTI > In addition, the computer-readable recording medium may be distributed over networked computer systems, and thus may include forms of computer readable code in a distributed computing manner.

All terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs, unless otherwise defined. Commonly used predefined terms should be interpreted to be consistent with the meanings in the context of the related art and can not be interpreted as having ideal or overly formal meaning unless explicitly defined in the present invention.

As used herein, the term "master coin" is used as a mediator for transactions between branch coins as a coin for inter-country transactions. Master Coin is listed on the International Virtual Currency Exchange and can be traded internationally with Bitcoin, Etherium, Light Coin, Dash, Ripple and so on.

As used herein, "branch coin" is a coin responsible for the local currency of a country for each of a plurality of countries. It is possible to trade only a branch coin of a country through a certain country virtual money exchange.

FIG. 1 is a network diagram illustrating a financial transaction processing system using a dual coin according to an embodiment of the present invention. Referring to FIG.

Referring to FIG. 1, a financial transaction processing system using a double coin includes a master coin exchange server 100 and a plurality of branch coin exchange servers 200_1 to 200_N.

The master coin exchange server 100 is a server located in the master coin exchange for managing master coins for inter-country transactions.

The information of the master coin is stored in a block of the master coin, and the block of the master coin is used for the coin transaction such as existing bit coin and etherium, the unique attribute of the coin such as block, mining, block chain, They all have similar characteristics but are not the same. The field of the block header of the master coin may be composed of version information of 2 bytes, a previous block of 32 bytes, a merge route of 32 bytes, a time stamp of 4 bytes, a difficulty target of 1 byte, and a 4 byte non-miss.

The master coin exchange server 100 generates a purse address of the master coin and stores it in the block of the master coin of the block chain of the block chain server (not shown). The master coin's wallet address consists of 34 digits and letters.

When the master coin exchange server 100 receives the financial transaction processing message from the branch coin exchange server 200_1 located at the branch coin exchange of a particular country among the plurality of branch coin exchange servers 200_1 to 200_N, Depending on the type, financial transactions are processed using the master coin.

In one embodiment, when the financial transaction processing message received from the specific branch coin exchange server 200_1 of the plurality of branch coin exchange servers 200_1 to 200_N instructs exchange processing to a specific currency, the master coin exchange server 100 , The branch coin can be exchanged into a specific currency using the master coin as an intermediary.

At this time, the master coin exchange server 100 may determine the exchange rate using Equation (1) below, and convert the branch coin into a specific currency using the master coin as an intermediary according to the exchange rate.

[Equation 1]

For example, the master coin exchange server 100 receives the financial transaction processing message received from the specific branch coin exchange server 200_1 of the plurality of branch coin exchange servers 200_1 to 200_N as a branch coin When the exchange process is instructed, the master coin can be exchanged to the branch coin of another country after the branch coin is exchanged to the master coin.

In the above embodiment, the master coin exchange server 100 subtracts the branch coin requested for exchange from the purse of the branch coin, converts the subtracted branch coin to the master coin, and then exchanges the specific coin using the master coin .

In addition, the master coin exchange server 100 verifies the master coin block because it uses a distributed book based on a block chain in a block chain server (not shown).

The master coin exchange server 100 verifies the block of the master coin using the following formula (2) to verify the block by the Proof of Work (PoW) method, and after the lapse of a predetermined time, The block of the master coin is verified using the following equation (3) to verify the block by the Proof of Stake (PoS) method.

At this time, the master coin exchange server 100 proves the block of the master coin by using the proof of equity as well as the proof of work because the currency of the work proof system such as bit coin is one that the value of the currency is rapidly Which will lead to an increase in deflation.

&Quot; (2) "

h (n-1 th block header | nonce) < f (D)

h: hash function,

n: block height,

nonce: number of 32bits incremented by 1,

D: Difficulty,

f: target value calculation function

&Quot; (3) &quot;

h (n-1 th block header | nonce)? f (bal (A), D)

h: hash function,

n: block height,

nonce: number of 32bits incremented by 1,

D: Difficulty,

bal (A): ownership of A%

f: target value calculation function

The plurality of branch coin exchange servers 200_1 to 200_N are servers located on the branch coin exchange for managing the branch coins of the respective countries for each of a plurality of countries.

The branch coin information is stored in a branch coin block. The branch coin block includes 2-byte version information, 32-byte old block decoding, 32-byte Merkroot, 4-byte time stamp, 1-byte difficulty target, Can be composed of nuns.

The transaction data structure of the branch coin comprises at least one of an identifier, a transmission source, a destination, a type, a total amount, a time stamp, a check sum, a version, a script sign and a message signed with a private key.

The type determines a type of transaction, and if the type is a currency, interprets the type of transaction as performing a function of money and determines the content of the message as a general message.

If the type is a smart contract, the type of the transaction is interpreted as performing another function in addition to the function of money, and if the type is a smart contract, the message includes a script code, an internet web address, It can be either.

Each of the plurality of branch coin exchange servers 200_1 to 200_N stores the private key, the public key, the purse address of the branch coin, and the branch coin holding amount for each wallet of the branch coin into a block of a branch coin of a block chain of a block chain server (not shown) .

To this end, each of the plurality of branch coin exchange servers 200_1 to 200_N generates a purse address of the branch coin, and the purse address of the branch coin is composed of 37 digits and a character string.

The branch coin's purse address is three digits longer than the master coin's purse address. These three digits are the two domain codes and one checksum. The domain code is added for easy identification of the country where the branch coin is used, and the domain code is shown in capital letters. For example, KR for Korea, JP for Japan, CN for China.

Therefore, even if you look at the address of the coin of the branch coin, it is easy to see which coin is the coin in the coin of the branch coin.

In addition, each of the plurality of branch coin exchange servers 200_1 to 200_N immediately subtracts the corresponding branch coin from the purse of the branch coin when converting a certain amount of branch coin in the purse of the branch coin into the paper purse according to the user's request.

Then, each of the plurality of branch coin exchange servers 200_1 to 200_N stores information on the private key of the paper wallet, the coin holding amount, and the like in the block of the branch coin of the block chain of the block chain server (not shown). As described above, since the contents of the paper wallet are stored in the block chain, it is possible to switch the paper wallet to the branch coin later.

In addition, each of the plurality of branch coin exchange servers 200_1 to 200_N, when exchanging the paper wallet with the branch coin at the request of the user, is provided in a block of a branch coin of a block chain of a block chain server (not shown) The information can be used to exchange the branch coin for the holding coin of the paper wallet.

When a plurality of branch coin exchange servers 200_1 to 200_N receives a financial transaction request message using a branch coin from a user terminal (not shown), the plurality of branch coin exchange servers 200_1 to 200_N interwork with the master coin exchange server 100 according to the type of the financial transaction processing request message And processes the financial transaction by using the branch coin in the inside.

In one embodiment, each of the plurality of branch coin exchange servers 200_1 to 200_N processes the financial transaction in cooperation with the master coin exchange server 100 when the financial transaction processing request message instructs overseas remittance or overseas settlement.

More specifically, each of the plurality of branch coin exchange servers 200_1 to 200_N provides a financial transaction processing message for instructing the master coin exchange server 100 to send an overseas remittance or an overseas settlement, Receives the processing result message for the transaction processing message, and provides the processing result message to the corresponding user terminal.

In another embodiment, each of the plurality of branch coin exchange servers 200_1 to 200_N processes the financial transaction using the branch coin internally if the financial transaction processing request message instructs domestic remittance, domestic settlement, or purchase price settlement do.

More specifically, each of the plurality of branch coin exchange servers 200_1 to 200_N subtracts the requested branch coin from the purse of the branch coin based on the financial transaction processing request message, Process purchase payment.

In addition, each of the plurality of branch coin exchange servers 200_1 to 200_N verifies the block of the branch coin because it uses the distributed book based on the block chain in the block chain server (not shown).

Each of the plurality of branch coin exchange servers 200_1 to 200_N proves a block of a branch coin using the following formula (4) to verify a block by a proof of work (PoW) method, The block of the branch coin is proved using the following equation (5) to verify the block by the Proof of Activity (PoA) method.

&Quot; (4) &quot;

h (n-1 th block header | nonce) < f (D)

h: hash function,

n: block height,

nonce: number of 32bits incremented by 1,

D: Difficulty,

f: target value calculation function

&Quot; (5) &quot;

h (n-1 th block header | nonce) < f (D ')

h: hash function,

n: block height,

nonce: number of 32bits incremented by 1,

D ': Difficulty lower than D in [Equation 4]

f: target value calculation function

2 is an exemplary diagram illustrating a data structure of a master coin block according to an embodiment of the present invention.

Referring to FIG. 2, the master coin information is stored in a block of a master coin, and the block of the master coin is a coin such as a coin transaction, a block, a mining block chain, But it is not the same.

The field of the block header of the master coin includes version information of 2 bytes, Previous Hash of 32 bytes, Markle Root of 32 bytes, Timestamp of 4 bytes, Diffculty Target of 1 byte, And may be composed of 4 bytes of Nonce.

The version information means the version number for the software / protocol upgrade trace, the previous block hash means the reference information for the hash of the previous block in the chain, and the merult means the hash of the root of the block transaction's merge tree , The time stamp means the approximate generation time of the block, the difficulty target means the difficulty target for the block's operation proof algorithm, and the nonce means the counter used in the operation proof algorithm.

3 to 5 are diagrams for explaining a data structure of a transaction of a master coin according to an embodiment of the present invention.

3 to 5, the transaction structure of the master coin may include an identifier (ID), a From, a To, a total amount, a timestamp, a checksum ), A version, a script signature (ScriptSign) signed with a private key, and a message.

As shown in FIG. 3, the transaction data structure includes an identifier, a transmission source, a destination, a type, a total amount, a time stamp, a checksum, a version, and a script signature and a message signed by a private key in a transaction of a branch coin.

As shown in FIG. 4, in the case of a branch coin transmission transaction, the data structure of the transaction is composed of an identifier, a destination, a total amount, a type stamp, a checksum, and a version.

As shown in FIG. 5, in the case of a receive transaction of a branch coin, the data structure of the transaction is composed of an identifier, a sender, a total amount, a type stamp, a checksum, and a version.

6 is an exemplary diagram illustrating a data structure of a wallet of a master coin according to an embodiment of the present invention.

Referring to FIG. 6, the data structure of the wallet of the master coin consists of address, total amount, type stamp, checksum and version. At this time, the master coin's wallet address is 34 digits and consists of numbers and letters.

7 is an exemplary diagram illustrating a data structure of a branch coin according to an embodiment of the present invention.

Referring to FIG. 7, the branch coin information is stored in a branch coin block, and the branch coin block includes 2 bytes of version information, 32 bytes of Previous Hash, 32 bytes of Markle Root, , A 4-byte time stamp (Timestamp), a 1-byte difficulty target (Diffculty Target), and 4-byte nonce.

The version information means the version number for the software / protocol upgrade trace, the previous block hash means the reference information for the hash of the previous block in the chain, and the merult means the hash of the root of the block transaction's merge tree , The time stamp means the approximate generation time of the block, the difficulty target means the difficulty target for the block's operation proof algorithm, and the nonce means the counter used in the operation proof algorithm.

8 to 10 are diagrams for explaining a data structure of a transaction of a branch coin according to an embodiment of the present invention.

8 to 10, a transaction structure of a branch coin includes an identifier (ID), a From, a To, a Type, an Amount, a Timestamp, A checksum, a version, a script signature for signing a specific message with a private key, and a message.

As shown in FIG. 8, the transaction data structure includes an identifier, a transmission source, a destination, a type, a total amount, a time stamp, a checksum, a version, and a script signature and a message signed by a private key in a transaction of a branch coin.

Wherein the type of the transaction determines the type of the transaction, interprets the type of the transaction as performing the function of a currency when the type is a currency, judges the contents of the message as a general message, ), The type of the transaction is interpreted as performing another function in addition to the function of money, and if the type is a smart contract, the message can be any one of a script code, an internet web address, and an encrypted contract content.

As shown in FIG. 9, in the case of a branch coin transmission transaction, the data structure of the transaction is composed of an identifier, a destination, a total amount, a time stamp, a check sum, and a version.

As shown in FIG. 10, in the case of a receive transaction of a branch coin, the data structure of the transaction is composed of an identifier, a sender, a total amount, a timestamp, a checksum, and a version.

11 is an exemplary view for explaining a data structure of a purse of a branch coin according to an embodiment of the present invention. 12 is a view for explaining a country code of a branch coin according to an embodiment of the present invention.

Referring to FIG. 11, the data structure of the wallet of the branch coin is composed of an address, a total amount, a type stamp, a check sum, and a version.

At this time, the purse address of the branch coin is composed of 37 digits, a domain code indicating the type of country in which numbers, letters, and a branch coin are used, and a checksum. The branch coin's purse address is three digits longer than the master coin's purse address.

These three digits are the two domain codes and one checksum. The domain code is added for easy identification of the country where the branch coin is used, and the domain code is shown in capital letters. For example, KR for Korea, JP for Japan, CN for China.

As shown in Fig. 11, "KR" in Address "1CWURjttpjTraJt7nTYhP5Wfbz3n3iq3pU KR 5" means a domain code. Such a domain code may be changed according to the country where the branch coin is used as shown in FIG.

13 is a flowchart illustrating a process of generating a wallet address of a master coin according to an embodiment of the present invention.

Referring to FIG. 13, the master coin exchange server 100 receives a public key (step S101).

The master coin exchange server 100 applies the public key to the multiple hash algorithm (step S102).

In one embodiment of step S102, the master coin exchange server 100 applies a multiple hash algorithm using SHA256 or X11. SHA256 is a cryptographic hash function adopted by the US NIST as standard and corresponds to the SHA-2 type. X11 is a multiple hash algorithm using 11 algorithms. X11 is a hash algorithm used by Dash, which has a very difficult feature to develop into an application-specific semiconductor (ASIC) due to this complicated algorithm.

The master coin exchange server 100 generates a message summary (step S103).

In one embodiment of step S103, the master coin exchange server 100 uses the RIPEMD 160 to generate a message digest. RIPEMD160 is a cryptographic hash algorithm developed on the basis of MD4, which generates a 160-bit message digest.

The master coin exchange server 100 generates a public key hash (step S104).

The master coin exchange server 100 encodes the public key hash (step S105).

In one embodiment of step S105, the master coin exchange server 100 encodes the public key hash using Base58Check. Base58Check has additional security features such as Base58 based encoding algorithm, Base58 error and data input error.

The master coin exchange server 100 generates the purse address of the master coin (step S106).

The description of the present invention described above is only an example for structural or functional description, and thus the scope of the present invention should not be construed as being limited by the embodiments described in the text. That is, the present invention is not limited to the above-described embodiments and the attached drawings, but is limited by the following claims, and the constitution of the present invention is not limited to the above- It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the scope of the present invention includes equivalents capable of realizing the technical idea.

100: Master Coin Exchange Server
200_1 ~ 200_N: Branch Coin Exchange Server

Claims (10)

When receiving a financial transaction processing message from a branch coin exchange server located at a master coin exchange managing a master coin for transactions between countries and located at a branch coin exchange of a specific country among a plurality of countries or from a user terminal, A master coin exchange server for processing a financial transaction using the master coin according to a kind of a message; And
Wherein the master coin exchange is located at a branch coin exchange for managing a branch coin of a corresponding country for each of a plurality of countries and upon receiving a financial transaction request message using a branch coin from a user terminal, And a plurality of branch coin exchange servers for processing financial transactions in cooperation with the server or for processing financial transactions using the branch coin therein
Financial Transaction Processing System using Double Coin.
The method according to claim 1,
The branch coin exchange server
If the financial transaction processing request message instructs domestic remittance, domestic settlement, or purchase payment, the financial transaction is processed using the branch coin, and when the financial transaction processing request message instructs overseas remittance or overseas settlement, Characterized by processing financial transactions through the server
Financial Transaction Processing System using Double Coin.
3. The method of claim 2,
The branch coin exchange server
Processing the domestic remittance, the domestic settlement, or the purchase settlement using the branch coin after deducting the requested branch coin from the purse of the branch coin based on the financial transaction processing request message,
Financial Transaction Processing System using Double Coin.
3. The method of claim 2,
The master coin exchange server
Wherein when a financial transaction processing message received from a specific branch coin exchange server instructs a currency conversion to a specific currency among the plurality of branch coin exchange servers, the central processing unit exchanges the branch coin into a specific currency using the master coin as an intermediary
Financial Transaction Processing System using Double Coin.
The method according to claim 1,
The address of the wallet of the master coin is composed of numbers and letters,
The purse address of the branch coin is composed of 37 digits, and is constituted by a domain code indicating the type of country in which numbers, letters, and a branch coin are used, and a checksum.
Financial Transaction Processing System using Double Coin.
6. The method of claim 5,
The domain code
It is used for the purpose of easily identifying the country where the branch coin is used, and is written in capital letters
Financial Transaction Processing System using Double Coin.
The method according to claim 1,
The master coin exchange server
The block of the master coin is proved by a Proof of Work (PoW) method, and a block of the master coin is proved by a proof of stake (PoS) method after a predetermined time has elapsed
Financial Transaction Processing System using Double Coin.
The method according to claim 1,
The branch coin exchange server
The method of proving a block of a branch coin by proving a block of a branch coin using the proof of work method and proving a block of the branch coin by a Proof of Activity (PoA) method after a predetermined time elapses, And calculates a coin to compensate for the branch coin of the compensation coin.
Financial Transaction Processing System using Double Coin.
The method according to claim 1,
The transaction structure of the branch coin
A signature, and a message signing the identifier, the transmission source, the destination, the type, the total amount, the time stamp, the checksum, the version, and the specific message with the private key,
The transaction structure of the master coin
A transaction name, an identifier, a transmission source, a destination, a total amount, a time stamp, a check sum, a version, a script sign, and a message depending on the type of transaction
Financial Transaction Processing System using Double Coin.
10. The method of claim 9,
The type of the transaction determines the type of the transaction. If the type is a currency, the type of the transaction is interpreted as performing a function of money, the content of the message is determined as a general message,
If the type is a smart contract, the type of the transaction is interpreted as performing another function in addition to the function of money, and if the type is a smart contract, the message may be a script code, an Internet web address, Characterized in that
Financial Transaction Processing System using Double Coin.

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