KR102014647B1 - Electronic voting method based on blockchain - Google Patents

Abstract

The present invention relates to a blockchain-based electronic voting method which comprises the steps of: distributing a smart contract to a blockchain network; storing an encoded account address and a user ID generated based on the user ID and a password inputted by a user in a database by a plurality of users; extracting the account address for the one user based on an identifier and the password inputted by the one user of the plurality of users; and distributing a result of voting to the blockchain network by specifying a session value using the account address extracted by the one user as a starting address.

Description

Blockchain-based electronic voting method {ELECTRONIC VOTING METHOD BASED ON BLOCKCHAIN}

The technology described below relates to an electronic voting technique implemented on a blockchain.

With the development of information and communication technology, the development of online voting system has led to the introduction of electronic voting system in major countries of the world. Because electronic voting is very public, technical security and stability must be perfect.

Blockchain technology, which has been actively applied in the existing financial sector, is gradually expanding to other fields. Online voting is also expected to be an application of blockchain technology.

Korea Patent Registration No. 10-1833323

Electronic voting is not completely guaranteed because of the possibility of tampering or manipulation of the data. The technology described below is intended to provide an electronic voting technique using blockchain technology.

In the blockchain-based electronic voting method, a smart contract is distributed to a blockchain network, an encrypted account address generated based on a user ID and password input by a user for each of a plurality of users, and the user ID is stored in a database. Storing, extracting an account address for the one user based on an identifier and a password input by any one of the plurality of users, and using the extracted account address as a starting address. And voting by specifying a session value is distributed to the blockchain network.

The technique described below provides an electronic voting scheme with a very low possibility of data tampering by external attacks using blockchain technology.

In blockchain technology, blockchain nodes share data. Therefore, the application of blockchain to electronic voting ensures confidentiality. The technology described below provides an electronic voting method that can guarantee anonymity of voters while being based on blockchain.

1 is an example of a structural diagram for a blockchain-based electronic voting system.
2 is an example of a flow diagram for an electronic voting process based on the system of FIG.
3 is another example of a structural diagram of a blockchain-based electronic voting system.
4 is an example of a flow diagram for an electronic voting process based on the system of FIG. 3.
5 is an example for a smart contract.

The following description may be made in various ways and have a variety of embodiments, specific embodiments will be illustrated in the drawings and described in detail. However, this is not intended to limit the technology described below to specific embodiments, it should be understood to include all changes, equivalents, and substitutes included in the spirit and scope of the technology described below.

The terms first, second, A, B, etc. may be used to describe various components, but the components are not limited by the terms, but merely to distinguish one component from other components. Only used as For example, the first component may be referred to as the second component, and similarly, the second component may be referred to as the first component without departing from the scope of the technology described below. The term and / or includes a combination of a plurality of related items or any item of a plurality of related items.

As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It is to be understood that the present invention means that there is a part or a combination thereof, and does not exclude the presence or addition possibility of one or more other features or numbers, step operation components, parts or combinations thereof.

Prior to the detailed description of the drawings, it is to be clear that the division of the components in the present specification is only divided by the main function of each component. That is, two or more components to be described below may be combined into one component, or one component may be provided divided into two or more for each function. Each of the components to be described below may additionally perform some or all of the functions of other components in addition to the main functions of the components, and some of the main functions of each of the components are different. Of course, it may be carried out exclusively by.

In addition, in carrying out the method or operation method, each process constituting the method may occur differently from the stated order unless the context clearly indicates a specific order. That is, each process may occur in the same order as specified, may be performed substantially simultaneously, or may be performed in the reverse order.

First, the blockchain technology will be briefly described.

Blockchain refers to a decentralized digital ledger that discloses content to all trading participants, unlike traditional methods of keeping records on a centralized server when trading data. It is a storage platform designed to prevent arbitrary manipulation of a specific person by all members participating in the blockchain verifying and storing data with each other through a network. This mutual distributed ledger ensures high security, scalability and transparency beyond the existing centralized network-based infrastructure.

The characteristic of blockchain is that the transaction records are organized in 'blocks' and continued over time. One block contains the connection information that connects the previous block and the next block, and if you change the contents of the previous block, you must recreate all the blocks that follow. Therefore, it is difficult to manipulate the contents of past blocks. Conversely, if a transaction record exists at some point in the past, it is objectively known that the transaction was made at that point, which is also important.

Blockchain is a decentralized ledger structure, where everyone who participates in the blockchain network owns a ledger that records all transactions. Therefore, if you use blockchain technology, it is operated by blockchain, which is a decentralized transaction book without a separate transaction management agency, so it has the advantage of low system maintenance cost and blocking hacking. In a distributed ledger environment, when a user requests a remittance transaction, a block in which transaction information is recorded is generated and the block is transmitted to all participants in the network. At this time, if each participant approves the transmitted block, the transaction is added to the existing blockchain and the transaction is completed. It is virtually impossible for hackers to hack the blockchain of global network participants at the same time because it is necessary to confirm that the majority of all Bitcoin network participants have the same information in order to modify the transaction information contained in the existing blockchain.

The blockchain uses a consensus algorithm to examine the validity of the blocks created by each node and reflect them on the blockchain shared throughout the network. Representative consensus algorithms used in the blockchain include Proof of Work (PoW), Proof of Stake (POS), and Practical Byzantine Fault Tolerance (PBFT).

 Blockchain 1.0 has been a major feature of digital currency issuance, distribution and trading. Blockchain 2.0 is evolving with the goal of overcoming the limitations of existing Bitcoin and expanding into various areas. The representative technology of Blockchain 2.0 is Ethereum, which implements Smart Contract, which makes Bitcoin's transaction scripts programmable in various forms as well as the functions of digital currency.

Ethereum has been extended to a platform that can develop and run various distributed applications on a blockchain basis. Blockchain platform is an environment that provides the components (distributed network, communication protocol, etc.) and necessary functions (transaction information verification, agreement, node management functions, etc.) of blockchain system so that blockchain services can be developed and tested. . By using the platform in developing blockchain services, it is possible to secure development convenience, interoperability and stability between services.

Ethereum can use a Turing-complete programming language. Coded rules allow users to write "contracts" that include the ability to transform "some state" differently. Smart contracts program the transaction to run automatically when certain conditions are met through the blockchain.

The technology described below relates to an electronic voting method or an electronic voting system based on a blockchain. For the convenience of explanation, the following electronic voting is assumed to be based on Ethereum. As described above, Ethereum may use a smart contract to perform certain operations or state changes programmed in the blockchain.

Hereinafter, the administrator refers to a subject who creates and manages electronic voting. Voter means a person who participates in a specific electronic ballot and votes on a particular candidate.

The administrator and the voter manage and proceed with the electronic voting using the terminal, which is a computer device. The terminal refers to a computer device capable of constant operation. For example, the terminal includes a PC, a notebook computer, a smart device, and a terminal for electronic voting.

1 is an example of a structural diagram of a blockchain-based electronic voting system.

The manager A generates information for the electronic voting using the manager terminal 10 and manages the electronic voting process. The manager terminal 10 may access the electronic voting system through a web browser. Alternatively, the manager terminal 10 may execute a dedicated application to feed the electronic voting system. 1 illustrates an example of accessing an electronic voting system through a web browser.

Voter B performs electronic voting using voter terminal 20. The voter terminal 10 may access the electronic voting system through a web browser. Alternatively, the voter terminal 10 may execute a dedicated application to feed the electronic voting system. 1 illustrates an example of accessing an electronic voting system through a web browser.

The electronic voting system is composed of a database 80 and a blockchain network 100. The database 80 stores certain information for each voter. The database 80 may store voter IDs (identifiers), account addresses for voters, voting contract addresses, and the like.

The blockchain network 100 is physically composed of a plurality of nodes. A node is an object connected on a network that is a device with a constant storage medium. For example, the node may be implemented as a server, a PC, or the like. Blocks hold contracts. Blockchain can store account address, contract address, transaction address, secret key, etc.

In the case of Ethereum, the blockchain constitutes an Ethereum Virtual Machine (EVM). EVM is the runtime environment for Ethereum smart contracts. EVM is a virtual machine that is shared by nodes in this blockchain network. EVM performs certain operations (state changes) according to a consensus algorithm.

2 is an example of a flow diagram for an electronic voting process 200 based on the system of FIG. 1. 2 illustrates one voter terminal 20 as an example. Do the same for multiple individual voters.

The voter registers for electronic voting through the voter terminal 20 (201). Voters enter a user ID and password by default during the registration process. The user ID and password are sent to the blockchain network 100 (202).

In the blockchain network 100, the EVM generates an account address based on the user ID (211). In this case, the generated account address corresponds to an address representing the user. EVM can generate account addresses using hash functions. The EVM encrypts the generated account address using a password (211). EVM encrypts account addresses using a constant encryption key. As the encryption method, various methods may be used. For example, the encryption scheme may be AES (Advanced Encryption Standard).

The database 80 receives (212) and stores an encrypted account address generated using the user ID and the corresponding user ID from the blockchain network 100 (221).

In FIG. 2, the EVM performs account address generation and encryption. In some cases, the voter terminal 20 may generate an account address based on its user ID, and may encrypt the account address based on its own password. In this case, the voter terminal 20 may transmit the encrypted account address and the user ID to the database 80.

The manager terminal 10 creates a contract including the contents of the vote (231). The manager terminal 10 inputs a voting start time (date), a voting end time, a candidate list, and the like. The manager terminal 10 distributes the generated contract to the blockchain network 100 based on the input information (232). The manager terminal 10 transmits the generated transaction based on the input information to the blockchain network (232).

It then explains how voters perform their votes. The voter logs in through the voter terminal 20 (241). If the login succeeds, the voter authenticates as a normal voter. Although not shown in FIG. 1, a voter database that separately holds voter information may be used. The voter database may hold a voter ID and the voter's password.

If the login is successful, the voter terminal 20 transmits the user ID to the database 80 (242). The voter terminal 20 receives an encrypted account address that matches its user ID from the database 80 (243). The voter terminal 20 decrypts the encrypted account address with its own password (251).

The voter terminal 20 designates the session value of the decoded account address (261). The voter terminal 20 transmits the decoded account address or session value to the blockchain network 100 (261). The voter terminal 20 receives voting information (contract) from the blockchain network 100 (262). For example, a successful voter can check the vote list when a particular account is opened. If there are multiple votes, the voter selects a specific vote, and the candidate list can be checked by reading the election contract stored in the blockchain.

The voter terminal 20 performs a vote (271). A detailed voting process will be described later. The voter terminal 20 performs voting by specifying the session value as the starting address of the decoded account address. When the voter exercises the right to vote, a transaction occurs based on the candidate information and is transmitted to the blockchain network 100. The voter terminal 20 transmits (distributes) the voting transaction to the blockchain network (281).

Although FIG. 2 has been described on the premise of a symmetric key encryption method, a public key encryption method may be used. In this case, the database 80 encrypts the account address using the public key instead of the user secret key, and the voter terminal 20 may decrypt the encrypted account address with its own password, which is the secret key.

3 is another example of a structural diagram of a blockchain-based electronic voting system. In FIG. 3, the electronic voting system, unlike FIG. 1, has a service server 50. The service server 50 provides a control and a service for performing the electronic voting. Other configurations are similar to the same as those of the electronic voting system of FIG.

The manager A generates information for the electronic voting using the manager terminal 10 and manages the electronic voting process. The manager terminal 10 may access the electronic voting system through a web browser. Alternatively, the manager terminal 10 may execute a dedicated application to feed the electronic voting system. 1 illustrates an example of accessing an electronic voting system through a web browser.

Voter B performs electronic voting using voter terminal 20. The voter terminal 10 may access the electronic voting system through a web browser. Alternatively, the voter terminal 10 may execute a dedicated application to feed the electronic voting system. 1 illustrates an example of accessing an electronic voting system through a web browser.

The electronic voting system includes a service server 50, a database 80 and a blockchain network 100.

The service server 50 performs user registration, account address generation using a user ID, account address encryption, transaction delivery, and the like.

 The database 80 stores certain information for each voter. The database 80 may store voter IDs (identifiers), account addresses for voters, voting contract addresses, and the like.

The blockchain network 100 is physically composed of a plurality of nodes. A node is an object connected on a network that is a device with a constant storage medium. For example, the node may be implemented as a server, a PC, or the like. Blocks hold contracts. Blockchain can store account address, contract address, transaction address, secret key, etc.

In the case of Ethereum, the blockchain constitutes an Ethereum Virtual Machine (EVM). EVM is the runtime environment for Ethereum smart contracts. EVM is a virtual machine that is shared by nodes in this blockchain network. EVM performs certain operations (state changes) according to a consensus algorithm.

4 is an example of a flow diagram for an electronic voting process 300 based on the system of FIG. 3. 4 illustrates one voter terminal 20 as an example. Do the same for multiple individual voters.

The voter registers as a member for electronic voting through the voter terminal 20 (301). Voters enter a user ID and password by default during the registration process. The voter terminal 20 transmits the user ID and password to the service server 50 (302).

The service server 50 generates an account address based on the user ID. The service server 50 may generate an account address using a hash function or the like (311). In this case, the generated account address corresponds to an address representing the user. The service server 50 encrypts the generated account address using a password (311). That is, the service server 50 encrypts the account address using a predetermined encryption key. As the encryption method, various methods may be used. For example, the encryption scheme may be AES (Advanced Encryption Standard). The service server 50 transmits the encrypted account address generated using the user ID and the corresponding user ID to the database 80 (312). The database 80 matches and stores the user ID and the encrypted account address (313).

In FIG. 3, the service server 50 performs account address generation and encryption. In some cases, the voter terminal 20 may generate an account address based on its user ID, and may encrypt the account address based on its own password. In this case, the voter terminal 20 may transmit the encrypted account address and the user ID to the database 80 directly or through the service server 50.

The manager terminal 10 creates a contract including the contents of the vote (331). The manager terminal 10 inputs a voting start time (date), a voting end time, a candidate list, and the like. The manager terminal 10 transmits the generated contract based on the input information to the service server 50 (332), and the service server 50 distributes the blockchain network 100 (333). In some cases, the contract generated by the manager terminal may be directly distributed to the blockchain network 100.

It then explains how voters perform their votes. The voter logs in via the voter terminal 20 (341). If the login succeeds, the voter authenticates as a normal voter. Although not shown in FIG. 3, a voter database that separately holds voter information may be used. The voter database may hold a voter ID and the voter's password.

If the login is successful, the voter terminal 20 transmits the user ID to the service server 50 (342). The service server 50 transmits the user ID to the database 80 (343). The service server 50 receives an encrypted account address matching its user ID from the database 80 (344). The voter terminal 20 receives an encrypted account address matching its user ID from the service server 50 (345).

The voter terminal 20 decrypts the encrypted account address with its own password (351).

The voter terminal 20 transfers the decoded account address to the service server 50 by specifying a session value (361). The service server 50 transmits the decoded account address or session value to the blockchain network 100 (362).

The service server 50 receives voting information (contract) from the blockchain network 100 (363). The voter terminal 20 receives voting information (contract) from the blockchain network 100 via the service server 50 (364). For example, a successful voter can check the vote list when a particular account is opened. If there are multiple votes, the voter selects a specific vote, and the candidate list can be checked by reading the election contract stored in the blockchain.

The voter terminal 20 performs a vote (371). A detailed voting process will be described later. The voter terminal 20 performs voting by specifying the session value as the starting address of the decoded account address. When the voter casts his / her right to vote, a transaction occurs based on the candidate information, is transmitted to the service server 50 (381), and finally transmitted to the blockchain network 100 (382). The voter terminal 20 transmits (distributes) the voting transaction to the blockchain network.

Although FIG. 4 has been described on the premise of a symmetric key encryption method, a public key encryption method may be used. In this case, the service server 50 encrypts the account address using the public key instead of the user secret key, and the voter terminal 20 may decrypt the encrypted account address with its own password which is the secret key.

5 is an example for a smart contract. As described above, a smart contract corresponds to a program having a specific state change when certain conditions are met or occur in the blockchain. A contract has a unique contract owner (contractOwner), a candidate array (candidateList), and the votes of the candidates (votesReceived).

When a voter votes for a candidate in the web browser, the voteForCandidate function of the smart contract is called. The votesReceived value is increased by determining whether voters have performed their votes through the alreadyVoted function. When the vote is closed and the results are aggregated, the totalVotesFor function is called.

In addition, the electronic voting method as described above may be implemented as a program (or application) including an executable algorithm that can be executed on a computer. The program may be stored and provided in a non-transitory computer readable medium.

A non-transitory readable medium refers to a medium that stores data semi-permanently and is read by a device, not a medium storing data for a short time such as a register, a cache, a memory, and the like. Specifically, the various applications or programs described above may be stored and provided in a non-transitory readable medium such as a CD, a DVD, a hard disk, a Blu-ray disk, a USB, a memory card, a ROM, or the like.

The embodiments and the drawings attached to this specification are merely to clearly show a part of the technical idea included in the above-described technology, and those skilled in the art can easily make it within the scope of the technical idea included in the description and the drawings of the above-described technology. It will be apparent that both the inferred modifications and the specific embodiments are included in the scope of the above-described technology.

10: manager terminal
20: Voter Terminal
50: service server
80: database
100: blockchain network

Claims (11)

Distributing a smart contract including a contract owner, a candidate list, and a candidate number of candidates in a blockchain network;
Generating, by the virtual machine of the blockchain network, an account address based on the voter's ID, encrypting the generated account address with the voter's password and storing it in a database;
The blockchain network delivering the smart contract to the voter in response to a request having the voter's decoded account address as the session value; And
Receiving, by the blockchain network, a smart contract executed by voting from the voter,
The decrypted account address is an address generated by decrypting the encrypted account address received by the voter from the database with his / her password,
The smart contract is a blockchain-based electronic voting method that executes a function of checking whether the voter votes and updating the number of votes of the specific candidate when the voter votes on a particular candidate in the candidate list. delete delete The method of claim 1,
And the voter receives an encrypted account address matching the user's ID from the database, and decrypts the encrypted account address by decrypting the password with its own password. delete Generating, by the service server, an account address based on a user ID for each of a plurality of users, encrypting the generated account address with a corresponding user's password, and storing the encrypted account address in a database;
Distributing, by the service server, a smart contract including a contract owner, a candidate list, and a candidate vote count to a blockchain network;
The service server retrieving a matched encrypted account address from the database based on an identifier input by any one of the plurality of users and delivering the matched encrypted account address to the user;
Transmitting, by the service server, to the blockchain network a transaction in which the user sets the encrypted account address with the password of the one user as a session value;
Delivering, by the service server, the smart contract received from the blockchain network to the user in response to the transaction; And
Distributing, by the service server, the smart contract executed by one of the users by voting in the blockchain network,
The smart contract is a blockchain-based electronic voting method that executes a function of checking whether the voter votes and updating the number of votes of the specific candidate when a condition in which a voter votes for a particular candidate in the candidate list occurs. The method of claim 6,
The smart contract is a blockchain-based electronic voting method further comprises a voting start time and voting end time. The method of claim 6,
The service server generates the account address for each of the plurality of users based on the user ID entered in the registration step, and encrypts the account address based on the password entered in the registration step. Based electronic voting method. The method of claim 6,
The service server delivers the decoded account address to the one user, and distributes the transaction in which the voting is performed by specifying the session value as the starting address from the one user to the blockchain network. Blockchain based electronic voting method. delete A computer-readable recording medium having recorded thereon a program for executing the blockchain-based electronic voting method according to any one of claims 1 to 4.

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