• 한국정보시스템학회지:정보시스템연구
• /
• 제15권1호
• /
• pp.1-20
• /
• 2006

Peer-to-peer systems (P2P) are rapidly growing in importance on the Internet environment, quickly extending the range of their usage. However, peer-to-peer systems have not been widely applied in electronic commerce because they have not been established as an appropriate business model. Therefore, we firstly review the previous research relevant to peer-to-peer systems, and then analyze the business models for P2P systems presented by previous researchers. Furthermore, this study categorizes major issues in terms of the technical and business model aspects. On the basis of these reviews, we develop P2P electronic commerce systems based on the file sharing method between users, focusing on user interface friendliness. A developed P2P electronic commerce systems are programmed by using the C# based on the Microsoft.net solution. A database is implemented using the MSSQL2000. A main application technology is designed that P2P electronic commerce systems make it possible. for user to extend into BtoB Solution by using WSDL (Web Services Description Language), UDDI (Universal Description, Discovery, and Integration) and the XML that is a document for users. User interface is made as form of Internet messenger for a user's convenience and is possible to develop into a commodity transaction system based on XML. In this study, it is possible for the P2P electronic commerce system to have extended application to fields such as Internet shopping mall and property transaction in a nonprofit organization, a public institution and a large scale nonprofit institution that have a similar structure as compared with a structure of a nonprofit educational institution.

• KDI Journal of Economic Policy
• /
• 제41권1호
• /
• pp.15-41
• /
• 2019

This paper economically analyzes the benefits and concerns of the sharing economy and derives policy implications that could help to achieve the expected benefits and respond appropriately to any concerns. Primary benefits anticipated from the sharing economy are the creation of new transactions and promotional and market testing opportunities, and the main concerns include the crowding out of existing transactions as well as transaction and social risks. How these benefits and concerns are being realized in Korea is empirically examined by conducting a survey on participation experiences with the sharing economy. The sharing economy is expected to contribute to the enhancement of social welfare with its wide range of benefits if risk factors can be properly controlled. Accordingly, an institutional framework is needed to support the stable growth of the sharing economy, and the unique characteristics of non-professional, peer-to-peer transactions should be reflected in tandem with regulatory equity between existing and sharing economy suppliers. To do this, transaction-volume-based regulations are recommended. Furthermore, to secure regulatory effectiveness and to alleviate transaction risks, the pertinent obligations must be imposed on sharing platforms.

• 정보처리학회논문지A
• /
• 제13A권7호
• /
• pp.599-606
• /
• 2006

P2P 서비스는 서비스 참여자들의 행동을 관리하고 악의적인 행동을 수행하는 참여자들을 제어할 수 있는 별도의 관리 기관을 가지지 알기 때문에 악의적인 목적을 가진 참여자들은 더 많은 이익을 얻기 위해 올바르게 행동하는 사용자들에게 피해를 줄 수 있다. 그러므로, P2P 서비스 이용자들은 사전 트랜잭션 수행 경험이 없는 사용자들과 안전하게 트랜잭션을 수행하기 위하여 과거에 트랜잭션을 수행한 경험이 있는 사용자들에 의해 제공되는 정보인 '평판' 정보의 참조를 통해 악의적인 목적을 가진 사용자와 올바른 사용자를 구별할 수 있다. 그러나. 사용자들은 수행된 트랜잭션에 대해 고의적으로 거짓 평가를 줄 수 있고, 이러한 사용자들을 'liar'라 부른다. 본 논문에서는 평판 정보에 대한 정확성을 위해 liar를 감소시키는 새로운 평판 시스템을 제안하고 시뮬레이션을 통해 그 타당성을 보인다.

• KNOM Review
• /
• 제22권3호
• /
• pp.20-24
• /
• 2019

블록체인은 분산 원장 기반 기술로 블록체인 네트워크에 참여하는 모든 노드들은 P2P 네트워크로 연결되어 있다. 블록체인 네트워크에서 트랜잭션이 생성되면, 트랜잭션은 블록체인 노드들에 의해 전파되고 유효성을 검증 받는다. 검증된 트랜잭션은 P2P 네트워크를 통해 각 노드와 연결되어있는 Peer들에게 전송되고, Peer들은 트랜잭션을 메모리 풀에 보관한다. P2P 네트워크 특성상 블록체인 노드가 전달하는 트랜잭션의 수와 종류는 각 노드마다 달라 모든 노드들이 동일한 메모리 풀을갖지 못하는 문제가 발생함에 따라 메모리 풀에 저장되어있는 트랜잭션들은 거래 수수료 조작, 이중 지불 문제, DDos 공격탐지 등의 문제를 해결하기 위해 연구가 필요하다. 본 논문에서는 거래 수수료 조작, 이중 지불 문제, DDos공격 탐지 등과 같은 문제를 해결하기 앞서 메모리 풀의 트랜잭션들을 분석한다. 따라서 본 연구는 블록체인기술을 기반으로 구현된 암호화폐 시스템인 비트코인과 이더리움의 각 노드 메모리 풀에 저장되어있는 트랜잭션들을 수집하고 얼마만큼의 공통된 트랜잭션들을 가지고 있는지 자카드 유사도를 이용하여 분석한다.

• Journal of Information Processing Systems
• /
• 제16권3호
• /
• pp.699-717
• /
• 2020

Propagation time on permissionless blockchain plays a significant role in terms of stability and performance in the decentralized systems. A large number of activities are disseminated to the whole nodes in the decentralized peer-to-peer network, thus causing propagation delay. The stability of the system is our concern in the first place. The propagation delay opens up opportunities for attackers to apply their protocol. Either by accelerating or decelerating the propagation time directly without proper calculation, it brings numerous negative impacts to the entire blockchain system. In this paper, we thoroughly review and elaborate on several parameters related to the propagation time in such a system. We describe our findings in terms of data communication, transaction propagation, and the possibility of an interference attack that caused an extra propagation time. Furthermore, we present the influence of block size, consensus, and blockchain scalability, including the relation of parameters. In the last session, we remark several points associated with the propagation time and use cases to avoid dilemmas in the light of the experiments and literary works.

• 한국정보통신학회논문지
• /
• 제8권8호
• /
• pp.1760-1768
• /
• 2004

P2P(Peer-to-Peer)는 중앙서버 없이 개인간에 직접적인 연결을 통하여 디지털 자원(mp3, software, game, video 등)을 효과적으로 공유하는 방식으로 기존의 클라이언트/서버 방식과 달리 관련 프로그램만으로 디지털 자원에 대한 손쉬운 공유 및 교환이 가능하다. 본 논문에서는 이러한 P2P 기술을 서버가 중재자 역할을 하는 기존의 전자상거래 방식에 적용하여 구매자와 판매자가 직접적인 통신을 통하여 상거래를 수행할 수 있도록 한다. 또한, 특정 제품 구매시 해당 제품을 사용한 구매자들로부터 얻은 제품에 대한 신뢰값인 평판(reputation)을 참조하여 구매 제품에 대한 신뢰성을 향상시키고, 제품 교환과 지불이 정상적으로 수행될 수 있도록 보증 역할을 담당하는 ES(Escrow Server)를 사용하여 공정성(fairness)을 보장하는 P2P 방식의 새로운 e-Commerce 모델을 제안하고자 한다.

• 한국정보시스템학회지:정보시스템연구
• /
• 제25권2호
• /
• pp.79-110
• /
• 2016

목적 온라인 P2P 대출은 온라인 재무 중계업자를 통해 친분이 없는 개인 간의 대출을 가능하게 해주는 새로운 방법이다. 대체로 온라인 P2P 거래에서는 돈을 대출받고자 사람과 대부하고자 사람이 이전에 개인적인 관계가 없는 경우가 일반적이다. 광범위한 선행연구를 통해 본 연구에서는 온라인 P2P 플랫폼을 통한 대출의도에 미치는 영향요인을 파악하기 위한 연구모형을 구축하였고, 중국 온라인 P2P 대출업체 중에서 가장 규모가 큰 런런다이 사례를 중심으로 실증분석을 실시하였다. 설계/방법론/접근 연구가설을 검증하기 위해 본 연구에서는 42개 문항으로 구성된 설문지를 개발하였고, 모든 항목은 리커트 5점 척도를 사용하였다. 중국 설문조사 전문 웹사이트인 sojump.com을 통해 런런다이 서비스 가입자 246명을 대상으로 설문조사를 실시하였고, 자료분석을 위해 SPSS 20.0과 AMOS 18.0을 사용하였다. 가설검증에 앞서 측정도구의 신뢰성, 타당성, 복합신뢰도 그리고 평균분산추출을 계산하였고, 동일방법편의(common method bias) 여부도 함께 진단하였다. 연구모형에서 매개변수로 사용된 플랫폼 신뢰와 대출자 신뢰에 대한 가설검증을 실시한 후 구조방정식을 이용하여 연구가설을 검증하였다. 시사점 연구결과 서비스품질, 정보품질, 구조적 보증, 인지도 그리고 명성은 온라인 P2P 대출 플랫폼에 대한 신뢰에 유의한 영향을 미치는 것으로 나타났다. 다음으로 인지도, 명성 그리고 지각된 위험은 대출자에 대한 신뢰와 대출의도에 유의한 영향을 미치는 것으로 나타났다. 세 번째로 신뢰경향은 대출자에 대한 신뢰에 정(+)의 영향을 미치는 것으로 나타났다. 마지막으로 인지도, 명성 그리고 지각된 위험, 플랫폼 신뢰, 대출자 신뢰는 대부자의 대출의도에 직접적인 영향을 미치는 것으로 나타났다.

• The Journal of Asian Finance, Economics and Business
• /
• 제7권7호
• /
• pp.85-93
• /
• 2020

In peer-to-peer (P2P) loan markets, as most lenders are unskilled and inexperienced ordinary individuals, it is important to know the characteristics of borrowers that significantly impact their repayment performance. This study investigates the effects and importance of borrowers' past repayment performance track record within the platform to identify its predictive power. To this end, I analyze the detailed loan repayment data from two leading P2P lending platforms in Korea using a Cox proportional hazard, multiple linear regression, and logit models. Furthermore, the predictive power of the factors proxied by borrowers' track records are evaluated through the receiver operating characteristic (ROC) curves. As a result, it is found that the borrowers' past track record within the platform have the most important impact on the repayment performance of their current loans. In addition, this study also reveals that the borrowers' track record is much more predictive of their repayment performance than any other factor. The findings of this study emphasize that individual lenders must take into account the quality of borrowers' past transaction history when making a funding decision, and that platform operators should actively share the borrowers' past records within the markets with lenders.

• Asia pacific journal of information systems
• /
• 제30권1호
• /
• pp.21-30
• /
• 2020

Bitcoin (BTC) is a type of cryptocurrency that supports transaction/payment of virtual money between BTC users without the presence of a central authority or any third party like bank. It uses some cryptographic techniques namely public- and private-keys, digital signature and cryptographic-hash functions, and they are used for making secure transactions and maintaining distributed public ledger called blockchain. In BTC system, each transaction signed by sender is broadcasted over the P2P (Peer-to-Peer) Bitcoin network and a set of such transactions collected over a period is hashed together with the previous block/other values to form a block known as candidate block, where the first block known as genesis-block was created independently. Before a candidate block to be the part of existing blockchain (chaining of blocks), a computation-intensive hard problem needs to be solved. A number of miners try to solve it and a winner earns some BTCs as inspiration. The miners have high computing and hardware resources, and they play key roles in BTC for blockchain formation. This paper mainly analyses the underlying cryptographic techniques, identifies some weaknesses and proposes their enhancements. For these, two modifications of BTC are suggested ― (i) All BTC users must use digital certificates for their authentication and (ii) Winning miner must give signature on the compressed data of a block for authentication of public blocks/blockchain.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제15권10호
• /
• pp.3627-3641
• /
• 2021

Fintech, which stands for financial technology, is growing fast globally since the economic crisis hit the United States in 2008. Fintech companies are striving to secure a competitive advantage over existing financial services by providing efficient financial services utilizing the latest technologies. Fintech companies can be classified into several areas according to their business solutions. Among the Fintech sector, peer-to-peer (P2P) lending companies are leading the domestic Fintech industry. P2P lending is a method of lending funds directly to individuals or businesses without an official financial institution participating as an intermediary in the transaction. The rapid growth of P2P lending companies has now reached a level that threatens secondary financial markets. However, as the growth rate increases, so does the potential risk factor. In addition to government laws to protect and regulate P2P lending, further measures to reduce the risk of P2P lending accidents have yet to keep up with the pace of market growth. Since most P2P lenders do not implement their own credit rating system, they rely on personal credit scores provided by credit rating agencies such as the NICE credit information service in Korea. However, it is hard for P2P lending companies to figure out the intentional loan default of the borrower since most borrowers' credit scores are not excellent. This study analyzed the voices of telephone conversation between the loan consultant and the borrower in order to verify if it is applicable to determine the personal credit score. Experimental results show that the change in pitch frequency and change in voice pitch frequency can be reliably identified, and this difference can be used to predict the loan defaults or use it to determine the underlying default risk. It has also been shown that parameters extracted from sample voice data can be used as a determinant for classifying the level of personal credit ratings.