• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.20 no.1
• /
• pp.35-44
• /
• 2020

The growing use of public blockchain-based virtual cryptocurrency calls for secure management of blockchain account information managed through cryptocurrency wallet programs. The previously proposed wallet program has high security in terms of managing an account's private key, but low security in managing an account's recovery phrase. Therefore, in this paper, we propose a safe management system of blockchain account recovery string based on the new user authentication method using the user's mobile device information and OTP technique to overcome the problem of the existing account recovery string management method. It also conducts an analysis of the proposed blockchain account recovery string management system based on the expected behavior scenario.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.19 no.4
• /
• pp.563-570
• /
• 2018

Existing online voting is not being used for public elections due to uncertainty about security threats, and offline voting costs a lot of money. As an alternative, blockchain is emerging. Applying blockchain technology to online voting will ensure transparency and confidentiality, because voter information and aggregate information are distributed and managed. Since a blockchain distributes the voting information, it will be more secure than existing central server - based online voting systems. If blockchain technology is applied to public elections, and the transparency and confidentiality of the voting information is guaranteed, the cost of voting will be greatly reduced. This paper tries to apply to an online voting system the Ethereum platform from among the blockchain technologies. Ethereum is a highly scalable blockchain technology that provides a smart contract based on the Solidity language to develop an online voting contract and to distribute the contract to each voter. Each voter votes on the contract that has been distributed, and the votes are distributed to other voters. The experiment verifies the consistency of the stored voting information.

• Smart Media Journal
• /
• v.12 no.2
• /
• pp.76-82
• /
• 2023

In the 4th industrial revolution, the blockchain that distributes and manages data through a P2P network is used as a new decentralized networking paradigm in various fields such as manufacturing, culture, and public service. However, with the advent of quantum computers, quantum algorithms that are able to break existing cryptosystems such as hash function, symmetric key, and public key cryptography have been introduced. Currently, because most major blockchain systems use an elliptic curve cryptography to generate signatures for transactions, they are insecure against the quantum adversary. For this reason, the research on the quantum-resistant blockchain that utilizes lattice-based cryptography for transaction signatures is needed. Therefore, in this paper, we propose a blind signature scheme for the blockchain in which the contents of the signature can be verified later, as well as signing by hiding the contents to be signed using lattice-based cryptography with the property of quantum resistance. In addition, we prove the security of the proposed scheme using a random oracle model.

• The Journal of the Convergence on Culture Technology
• /
• v.7 no.1
• /
• pp.608-614
• /
• 2021

Currently, blockchain-based public cryptocurrency (hereinafter referred to as cryptocurrency) cannot acquire status as a currency for transaction due to the economic policies of each country, but it is used as an alternative currency transaction method due to individual circumstances of some Internet users. With this trend, it is predicted that such cryptocurrency can be used in real life beyond the Internet in the near future. In this paper, a technical method for designing a cryptocurrency payment system based on LoRaWAN that can easily build a wireless Internet network infrastructure at low cost as a way to activate the use of cryptocurrency in real life is presented based on the LoRaWAN standard.

• The Journal of Society for e-Business Studies
• /
• v.26 no.1
• /
• pp.79-91
• /
• 2021

The public records of universities shall be classified according to the Enforcement Decree of the Public Records Act and public records management activities shall be carried out accordingly. Among various kinds of public records of the university, the records of performance management are still managed as paper documents, such as attendance books, answer sheets, and assignments, and the management system and methods of each school are different, making it difficult for the management manager to manage them. In this paper, we propose a service model that can perform blockchain-based records management of records related to performance at universities currently kept in paper documents. The proposed service is expected to reduce resource consumption, such as the cost, time and effort spent on storing and managing paper documents.

• Journal of Digital Convergence
• /
• v.19 no.10
• /
• pp.287-293
• /
• 2021

Recently, public certificates issued by nationally-recognized certification bodies have been abolished, and internet companies have issued their own common certificates as certification authority. The Electronic Signature Act was amended in a way to assign responsibility to Internet companies. As the use of a joint certificate issued by Internet companies as a certification authority is allowed, it is expected that the fraud damage caused by the theft of public key certificates will increase. We propose an authentication model that can be used in a security gateway that combines PKI with a blockchain with integrity and security. and to evaluate its practicality, we evaluated the security of the authentication model using Sugeno's hierarchical fuzzy integral, an evaluation method that excludes human subjectivity and importance degree using Delphi method by expert group. The blockchain-based joint certificate is expected to be used as a base technology for services that prevent reckless issuance and misuse of public certificates, and secure security and convenience.

• Journal of Platform Technology
• /
• v.11 no.2
• /
• pp.15-25
• /
• 2023

This study analyzes the limitations of the insider threat datasets used for insider threat detection research and compares and analyzes the solution-based insider threat data with public insider threat data using a security solution to overcome this. Through this, we design a data format suitable for insider threat detection and implement a system that can safely share insider threat information between different institutions and companies using blockchain technology. Currently, there is no dataset collected based on actual events in the insider threat dataset that is revealed to researchers. Public datasets are virtual synthetic data randomly created for research, and when used as a learning model, there are many limitations in the real environment. In this study, to improve these limitations, a private blockchain was designed to secure information sharing between institutions of different affiliations, and a method was derived to increase reliability and maintain information integrity and consistency through agreement and verification among participants. The proposed method is expected to collect data through an outflow threat collector and collect quality data sets that posed a threat, not synthetic data, through a blockchain-based sharing system, to solve the current outflow threat dataset problem and contribute to the insider threat detection model in the future.

• The Journal of Society for e-Business Studies
• /
• v.25 no.4
• /
• pp.111-124
• /
• 2020

Blockchain was proposed in 2007 and began to be applied to actual services soon afterward. The railway system covers railroad construction and railway services. Because of the public characteristics of the railway system, it is expected that significant advantages can be obtained through the introduction of blockchain. Many benefits can be gained by applying the blockchain to them, but it is impossible to apply the blockchain to every part immediately due to the limitations of time and resources. Therefore, it is necessary to derive services or functions to which the blockchain will be applied and to select the part of them first. Since there are various evaluation criteria to derive the priority of blockchain adoption, systematic consideration is required. In this study, AHP was applied to calculate weights for evaluation criteria and systematical evaluation. Through the results of this study, it is expected that it is possible to build a roadmap for a next-generation railway system.

• Journal of Internet Computing and Services
• /
• v.20 no.4
• /
• pp.1-11
• /
• 2019

A Blockchain-based access control technology is one of the various use cases of blockchain and is used in many areas to transparently transfer and manage ownership of data between users without the trusted third party. The characteristics of transparency, Irreversibility, and decentralization provided by the public blockchain help to offer new benefits that existing access control technologies did not offer. However, various security issues facing the current blockchain are raising the issue of the safety of the technology. Therefore, in this paper, we analyze an overview of the blockchain-based access control technology and solutions of the security challenges faced. Moreover, we further present solutions that are not affected by the blockchain trilemma and models of access control technology based on them.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2019.05a
• /
• pp.290-292
• /
• 2019

Since the advent of blockchain and bitcoin, decentralization has been accelerating around the world as a public blockchain ethereum with smartcontract has begun. Developers can use Ethereum's blockchain development platform to develop "distributed applications" (DApp) running on a decentralized P2P network, and various types of devices from IoT to mobile can participate in a block-chain distributed environment have. Using Ethereum's blockchain development platform, developers can develop "Decentralized Application (DApp)" that run on a decentralized P2P network and various types of devices from IOT to mobile can participate in distributed blockchain environments. There are many ways to interact with the blockchain and the smart contract, but users tend to prefer the mobile methods due to their convenience and accessibility advantages. Therefore, the author developed an Android based voting DApp and researched related issues. Since the current development methods of DApp are not adequately researched and standardized, efficient methods for developing user-friendly DApp were studied. Because DApp has to spend a certain amount of fees to interact with blockchain, it has intensively investigated the gas problem of Smart Contract code and the security problem of code, and author would like to introduce it in this paper.