• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2008.10a
• /
• pp.703-707
• /
• 2008

Nowadays, Internet becomes an essential element in our life. We can make use of numerous on-line services through Internet such as information search, on-line shopping, e-mail service, etc. But, while getting the benefits of Internet service, invasion of our privacy frequently occurs because on-line service providers tend to request excessive or unnecessary personal information. So, there have been some researches on anonymous authentication, which means that user can authenticate herself, not revealing her identity or personal information. But, most of the researches are not somewhat applicable to current authentication infrastructure. In this paper, we propose a pseudonym-based anonymous PKI with short group signature. Using our proposed scheme, we can provide anonymity with conditional traceability to current PKI.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.32 no.1C
• /
• pp.86-93
• /
• 2007

In this paper, we present an electronic voting system based on cryptographic techniques. Recently, some countries have used e-voting systems using an electronic voting device instead of a voting sheet. These e-voting systems are the early stage which is not online voting. Many cryptographers have studied on-line e-voting systems based on cryptographic techniques. The existing 1-out-of-L e-voting systems are based on E1Gamal cryptosystem. To reduce computational complexity, we use r-th residue encryption scheme and compare the computational complexity of our 1-out-of-L e-voting system with that of the 1-out-of-L e-voting system based on E1Gamal cryptosystem. Moreover, we extend the proposed 1-out-of-L e-voting system to ballot-cancellation property The existing e-voting systems had been overlooked the ballot-cancellation property. There is the reason that the ballot is cancelled according to an election law. For our e-voting system with ballot-cancellation property, we extend the homomorphic property based on r-th residue encryption. The extended homomorphic property is used to cancel votes with guaranteeing privacy and universal verifiability.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.22 no.3
• /
• pp.505-514
• /
• 2012

Because people usually establish their online social network based on their offline relationship, the social networks (i.e., the graph of friendship relationships) are often used to share contents. Mobile devices let it easier in these days, but it also increases the privacy risk such as access control of shared data and relationship exposure to untrusted server. To control the access on encrypted data and protect relationship from the server, M. Atallah et al. proposed a hop-based scheme in 2009. Their scheme assumed a distributed environment such as p2p, and each user in it shares encrypted data on their social network. On the other hand, it is very inefficient to keep their relationship private, so we propose an improved scheme. In this paper, among encrypted contents and relationships, some authenticated users can only access the data in distributed way. For this, we adopt 'circular-secure symmetric encryption' first. Proposed scheme guarantees the improved security and efficiency compared to the previous work.

• Journal of the Korea Society of Computer and Information
• /
• v.17 no.8
• /
• pp.145-161
• /
• 2012

This study aims to explore how the degree of education related to information systems and the Internet literacy affect perceived security risk and how these three variables affect online transaction intention based on the Technology Acceptance Model (TAM). Since using smartphone to purchase necessary products is increasing, the study provided two different cases of using the existing Internet and smartphone to buy products. As a result of an empirical test, the degree of information system education, internet literacy, and perceived security risk had significant effects on online transaction intention mediating perceived usefulness and perceived ease of use. Unlike the expectation, the more people have education related to information systems, the more they have knowledge about hacking or cases of privacy infringement, leading to even more concerns about security, thereby believing the Internet transactions require much effort. The more the education about information system, the more we have concerns about security; therefore, perceived security risk have a positive(+) effect on perceived usefulness not a negative(-) effect. Lastly, while the degree of education related to information systems has relations with the recognition of the usefulness of the Internet transaction, the study showed that there are no relations of recognizing the usefulness and the ease of use of smartphone.

• Management & Information Systems Review
• /
• v.33 no.5
• /
• pp.213-232
• /
• 2014

Sensitivity to online store stimuli (VMD attributes) and response (online store loyalty) may depend upon consumers' regulatory focus (emotional state). In other words, consumers' sensitivity to online store atmosphere and consequent store loyalty can be influenced by the match between their regulatory focus (promotion focused vs. prevention focused) and the type of the online store VMD benefits Study 1 results indicate consumers have a different evaluation about online store atmosphere depending on their regulatory focus. Promotion-focused consumers were significantly more sensitive to visual appeal and entertainment attributes of online store atmospherics than prevention-focused consumers. Conversely, prevention-focused consumers were significantly more sensitive to security and privacy attributes of online store, than promotion-focused consumers. Study 2 results indicate for promotion-focused shoppers, hedonic value toward online store atmosphere was associated with greater online store loyalty. In contrast, prevention-focused shoppers were influenced more by the utilitarian attributes on online store loyalty than promotion-focused shoppers. The current findings indicate that shoppers with promotion-focused are more easily persuaded by visual and entertainment-oriented online store cues. Conversely, shoppers with prevention-focus are more easily persuaded by safety and privacy-oriented online store cues.

• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.48 no.3
• /
• pp.18-26
• /
• 2011

Social network services whose users increase rapidly is the online services that reflect social network. They are used for various purposes such as strategy of election, commercial advertisement and marketing, educational information sharing and exchange of medical knowledge and opinions. These services make users form social networks with other users who have common interests and expand their relationships by releasing their personal information and utilizing other users' social networks. However, the social network services based on open and sharing of information raise various security threats such as violation of privacy and phishing. In this paper, we propose a group key management scheme and protocols using key rings to protect communication of small groups in social network services.

• Journal of Global Scholars of Marketing Science
• /
• v.7
• /
• pp.321-337
• /
• 2001

The Purpose of this study is to empirically examine the factors that affect the consumer's buying behavior under the e-commerce environment. In order to achieve this goal, vendor characteristics, securities of transaction, concern for privacy, shopping orientation and perceived channel utilities were used as independent variables. Findings of study indicated that the concerns for abusing individual information, perceived securities of transaction, consumer's recreational orientation, consumer's convenience orientation, perceived distribution channel are the robust predictors of buying behavior of internet users.

• The Journal of Information Systems
• /
• v.25 no.3
• /
• pp.197-215
• /
• 2016

Purpose This study aims to investigate the factors that influence decision making in relation to providing personal information on the internet with respect to the integration of the privacy calculus theory and protection motivation theory based on the dual-calculus model proposed by Li(2012). Design/methodology/approach The privacy calculus theory and protection motivation theory have been applied to explain privacy behavior to a certain degree but few studies have been conducted to explain privacy behavior based on the integration of these two theories. Although Li(2012) proposed the dual-calculus model, he only proposed its framework and did not carry out an empirical study. Therefore, this study proposes a research model that integrates these two theories and examines the relationship between the two theories through an empirical study. Findings According to the results of empirical analysis, it was found that all relations have statistically significant explanatory power except the relation between coping appraisal and privacy risk in the risk calculus process. Thus, the results verify that external threat played a decisive role in increasing the risk level of a consumer's privacy. It can be discussed the ways to enhance the privacy behavior of consumer on the internet through these findings.

• Proceedings of the KAIS Fall Conference
• /
• 2005.05a
• /
• pp.253-256
• /
• 2005

본 논문에서는 홈네트워크 기술을 통해 원격의료$\cdot$원격진료$\cdot$원격검침$\cdot$원격제어 등 편리한 생활이 가능하고, 대화형 TV$\cdot$VOD(Video On Demand)$\cdot$온라인 게임 등의 각종 오락을 가정에서 편리하게 즐길 수 있어 여가 시간을 효율적으로 활용 가능하게 하여 즐거운 가정을 이룰 수 있다. 방범$\cdot$방재$\cdot$안전한 개인정보 관리 등을 통해 개인 및 가정의 프라이버시를 보장받고, 도난$\cdot$재난 등을 24시간 방지하여 안전한 생활을 보장받을 수 있을 뿐 아니라, 양방향 홈쇼핑$\cdot$홈뱅킹$\cdot$에너지 관리 등 개인의 경제 활동을 가정에서 처리하고 전기$\cdot$가스등의 공공 자원을 외부에서 효율적으로 관리함으로써 윤택한 가정을 누릴 수 있는 홈네트워크 기술개발을 연구하였다.

• Convergence Security Journal
• /
• v.18 no.4
• /
• pp.3-10
• /
• 2018

Each online user should perform a separate registration and manage his ID and password for each online commerce or SNS service. Since a common secret is shared between the user and the SNS server, the server compromise induces the user privacy breach and financial loss. In this paper, it is considered that the user's authentication material is shared between multiple SNS servers for user authentication. A blockchain service architecture based on Hyperledger Fabric is proposed for each user to utilize an identical ID and OTP using the enhanced hash-chain-based OTP.