• KIPS Transactions on Computer and Communication Systems
• /
• v.9 no.12
• /
• pp.315-320
• /
• 2020

Identity authentication is an important technology that has long been used in society to identify individuals and provide appropriate services. With the development of the Internet infrastructure, many areas have expanded into online areas, and identity authentication technologies have also expanded online. However, there is still a limit to identity authentication technology that relies entirely on trusted third parties like the government. A centralized identity management system makes the identification process between agencies with different identity management systems very complex, resulting in a waste of money and time for users. In particular, the limits of the centralized identity management system were clearly revealed in the face mask shortage in the 2020 COVID-19 crisis. A Decentralized Identity (DID) is a way for users to manage their identity on their own, and recently, a number of DID platform based on blockchain technology have been proposed. In this paper, we analyze the limitations of the existing centralized identity management system and propose a DID system that can be utilized in future national emergency situations such as COVID-19.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2019.01a
• /
• pp.343-344
• /
• 2019

글로벌 게임 시장이 지난 몇 년간 두 자릿수 성장하여 지난 해 910억 달러의 매출을 기록하였으며, 모바일 게임과 같은 부문에서 가장 큰 성장이 있었지만 신기술은 게임 시장을 근본적으로 향상시켜 새로운 성장 기회를 제공 할 가능성이 있다. 그러한 기술 중 하나인 블록체인은 틀림없이 가장 큰 장기적인 잠재력을 가지고 있다. 본 논문에서는 게임 내 상품 거래에 문제가 되는 부분에 대해서 합법적인 거래를 통해 안전하고 지속적인 소유가 가능한 블록체인 기반의 탈중앙화를 지향해 모든 참여자가 권한을 갖는 분산형 개방 시스템 블록체인 기술의 필요성을 제시한다.

• Journal of the Korean Society of Industry Convergence
• /
• v.25 no.4_1
• /
• pp.513-519
• /
• 2022

In this paper, we describe performances of P-PD controllers in the quadrotor system with steady-state error compensation by adding a corrective term to the system input. A decentralized control system using P-PD controllers was successfully implemented on a quadrotor platform. We also presented the results of a mathematical modeling analysis for control the quadrotor and experimental results for each response performance according to the heading reference value in accordance with the mathematical modeling and P-PD controller design. A control experiment with the real system was implemented for the test platform, and the results were evaluated and compared.

• Journal of the Korea society of information convergence
• /
• v.5 no.2
• /
• pp.67-76
• /
• 2012

XML-based open protocol, XMPP users to pass messages to other users, which means that a decentralized communication network is the network infrastructure and enable it. In addition, XMPP servers using a professional server-to-server protocol to communicate with each other and decentralized social networks and collaboration framework provides an important possibility. In this paper, the features of XMPP messaging protocol is applicable to automotive telematics terminals XMPP-based platform design, and presence of two-way communication point for the problem, point-to-point session setup issues, security issues, compatibility issues, and to solve the scalability problem XMPP-based messaging system was implemented.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.31 no.5
• /
• pp.889-899
• /
• 2021

This paper proposes a reliable data sharing scheme on the internet of vehicles (IoV) by utilizing blockchain technology for constructing a decentralized system approach. In our model, to maintain the credibility of the information messages sent by the vehicles to the system, we propose a reputation rating mechanism, in which neighboring vehicles validate every received information message. Furthermore, we incorporate an incentive mechanism based on smart contracts, so that vehicles will get certain rewards from the system when they share correct traffic information messages. We simulated the IoV network using a discrete event simulator to analyze network performance, whereas the incentive model is designed by leveraging the smart contract available in the Ethereum platform.

• Information Systems Review
• /
• v.26 no.1
• /
• pp.151-172
• /
• 2024

Metaverse, which supports social and economic activities in the virtual world, is being cited as the core of future Web 3.0 businesses. However, most of the major metaverse platforms currently adhere to the Web 2.0 system and are operated in a centralized manner. Accordingly, this study investigated the form of metaverse operation by examining the case of Decentraland, a metaverse platform operated as DAO, a decentralized autonomous organization in the form of Web 3.0. From the case analysis, we found that Decentraland had positive characteristics such as a horizontal operating structure, fair profit distribution, and transparency, but there were challenges including the possibility of returning to centralization in the operating process, the possibility of abuse of an autonomous system, and inefficiency in decision-making. Therefore, in this study, the timing of transition to DAO governance was discussed, and DAO's efforts for business continuity and the need for adjustment for autonomous operation were suggested as implications. The implications presented in this study are expected to contribute to materializing not only practical but also theoretical aspects of platform operation aimed at web 3.0 as well as the metaverse.

• Journal of Digital Convergence
• /
• v.18 no.10
• /
• pp.253-263
• /
• 2020

Since the birth of the Ethereum in 2015, various decentralized applications (DApp) based on blockchain smart contract technology have appeared. However, CryptoKitty's case showed instability in terms of performance and scalability in real-world service environments. To solve this, a blockchain platform that developed a high transaction per second (TPS) has appeared, but there have been no environments and services to test it. Therefore, this paper intends to design and develop a game that can record the contents of all games on the chain and verify the performance and scalability of the blockchain platform through oversized transactions. The developed game generated a total of 6.3 million blocks and 8.9 million transactions through by 682 and verified the improved performance and scalability of the existing platform. Additionally, the maximum TPS was measured at 1,309 during the test period. In the future, it is expected that performance and scalability can be compared in a realistic environment through the method presented in this paper.

• Journal of Korea Multimedia Society
• /
• v.23 no.2
• /
• pp.262-273
• /
• 2020

This paper analyzes the existing copyright management and copyright sharing model and discusses the limitations. It then proposes a consortium Blockchain-based copyright management model in which the service platform participates as a node, and discusses how to combine the My Data concept with Blockchain and smart contracts. Also, Blockchain-based CP-ABE is introduced and applied to the proposed model as a way for users to define access policies and store copyright data in encrypted form on the storage of the online service providers (OSP). Compared with the existing copyright management model, the proposed model allows the copyright holder to focus on copyright registration, license content design, and sharing, as the data subject. And it is expected to be able to transparently manage the usage records and the basis for the settlement of the copyrighted data that are shared and used on each platform.

• Journal of Communications and Networks
• /
• v.6 no.4
• /
• pp.295-306
• /
• 2004

In this paper, a novel air-interface is presented for Fleet-Net1, a self-organizing network for inter-vehicle and vehicle-toroadsidecommunication. The air-interface is based upon the lowchip-rate version of UMTS/TDD. To adapt the cellular UMTS standard to an air-interface for ad hoc networks, changes of the physical layer, medium access control sub-layer and radio resource management are required. An overview of the required modifications is given here. Particularly, a decentralized synchronization mechanism is presented and analyzed by means of simulations. Furthermore, changes for the medium access control are explained in detail, which allow for an efficient operation in partly meshed networks and prioritization. Performance results of the overall system considering throughput and delay are derived by means of analytical evaluations and event-driven simulations. Based on realistic mobility models, it is shown that the presented solution provides a robust communication platform even in vehicular environments. The proposed air-interface is a cost-effective solution not only for inter-vehicle communication, but also for ad hoc networking in general, benefiting from the mass-market of UMTS.

• Proceedings of the KIEE Conference
• /
• 2005.10b
• /
• pp.394-396
• /
• 2005

In this paper, we propose an adaptive tracking control method of a mobile manipulator for contour following with a kinematic model to have several unknown dimension parameters. Moreover, we will use the decentralized control method to design two independent controllers for two subsystems. The proposed controllers in this paper are based on the Lyapunov function in order to guarantee the stability of whole system for contour following task. The updated laws are also designed to estimated the unknown dimension parameters. Finally, the simulation results are presented to show the validity of the proposed controllers in this paper.