• Proceedings of the Korean Information Science Society Conference
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• 2003.04a
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• pp.338-340
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• 2003

Certified E-mail 프로토콜은 공정한 교환(fair exchange)을 보장하기 위하여 신뢰된 제 3자 (Trusted Third Party, TTP)톨 사용한다. 그러므로, Certified E-mail을 사용하는 유저들은 원격지의 TTP를 완전히 신뢰(fully-trust)해야 한다. 만약 TTP가 훼손되거나 유저와 공모하여 악위적인 행동을 한다면 Certified E-mail 프로토콜의 공정성(fairness)은 붕괴된다. 본 논문에서는 Threshold secret sharing을 사용하여 TTP의 신뢰성을 분산시킨 강건한 Certified E-mail 프로토콜을 제안한다. 분산된 TTP(Distributed TTP, DTTP)를 사용하므로써 유저가 공모하는 악위적인(malicious) TTP에 대한 공격을 막을 수 있으며 어느 한 DTTP가 훼손되더라도 전체 프로토콜에 영향을 주지 못한다.

• Proceedings of the Korea Multimedia Society Conference
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• 2003.11a
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• pp.166-169
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• 2003

본 논문에서는 비밀분산기법과 임계 암호시스템을 사용하여 사용자의 공개키 암호 알고리즘 연산과 공개키 유효성 검증에 대한 연산의 오버헤드를 최소화시킨 새로운 Certified E-mail 시스템을 제안한다. 따라서, 제안 방안은 셀룰러 폰이나 무선 PDA와 같은 컴퓨팅 파워가 취약한 메일 사용자에게 적합하다 또한, 제안 시스템은 신뢰성을 완전히 분산시킨 TTP(Trusted Third Party)를 사용함으로써, TTP의 훼손이나 악의적인 사용자의 공모 공격에 강건하도록 설계되었다.

• Proceedings of the Korea Multimedia Society Conference
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• 2003.05b
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• pp.650-653
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• 2003

전자 메일(e-mail)은 현대인의 삶에서 매우 보편적으로 사용되고 있으며, 또한 비즈니스 측면에서도 필수적인 통신도구가 되고 있다. 현대 사회의 인프라가 온라인 환경으로 이동함에 따라서 전통적인 면대면(face-to-face)방식에서 예기치 못한 문제가 발생하고 있다. 하지만, 인터넷은 전자적 정보에 대한 안전하고, 공정한 교환(fair-exchange)과 같은 비즈니스 통신 모델에서 요구되는 서비스를 제공하지 못한다 본 논문에서는 기존의 보안 메일 기술인 S/MIME, PGP와는 차별화된 기술로서, 전달 메시지의 암호화는 물론 송·수신자 사이의 공정한 교환을 보장하는 Certified E-mail 시스템을 제안하고자 한다. 본 논문에서 제안하는 방안은 셀룰러 폰이나 PDA 사용자 단말기의 공개키 암호 알고리즘 연산에 따른 오버헤드를 최소화하도록 설계되었다.

• Journal of KIISE:Computing Practices and Letters
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• v.9 no.1
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• pp.86-94
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• 2003

Certified e-mail system guarantees that recipient will get mail content if and only if mall originator receives a receipt. Unlike previous schemes, Optimistic protocols recently published generate a receipt when it meets the condition that the mail content can be accessed by recliner at any time. So originator cannot assure the delivery of e-mail although he can get a receipt. In this paper, we show some flaws in optimistic protocols and propose improved schemes using delivery deadline. Modified protocols guarantee proof-of-receipt and eliminate the problem mentioned above. Furthermore, proposed modification technique can be applicable to most optimistic protocols and is efficient in the sense that modified schemes do not increase the number of messages.

• The KIPS Transactions:PartC
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• v.10C no.6
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• pp.825-834
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• 2003

In this paper, we propose a new certified e-mail system which reduces user's computational overhead and distributes confidentiality of TTP(Trusted Third Partty). Based on the traditional cryptographic schemes and server-supported signiture for fairness and confidentiality of message, we intend to minimize to computation overhead of mobile device on public key algorithm. Therefore, our proposal becomes to be suitable for mail user sho uses mobile devices such as cellular phone and PDA. Moreover, the proposed system is fault-tolerant, secure against mobile adversary and conspiracy attack, since it is based on the threshold cryptography on server-side.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.19 no.1
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• pp.3-11
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• 2009

Forward secrecy in an e-mail system means that the compromising of the long-term secret keys of the mail users and mail servers does not affect the confidentiality of the previous e-mail messages. Previous forward-secure e-mail protocols used the certified public keys of the users and thus needed PKI(Public Key Infrastructure). In this paper, we propose a password-based authenticated e-mail protocol providing forward secrecy. The proposed protocol does not require certified public keys and is sufficiently efficient to be executed on resource-restricted mobile devices.

• Journal of Intelligence and Information Systems
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• v.9 no.2
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• pp.39-50
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• 2003

Deleting unsolicited email, popularly known as spam mail, is an annoying task for Internet users. Moreover, spam mail causes a variety of social problems. At present, legal restrictions cannot eradicate spam senders. As a result, many technical methods to eliminate spam mail such as spam filtering and online stamps have been introduced. However, the process of blocking spam mail can inadvertently result in suspension of indispensable or beneficial communication. In this paper, we propose a certificate and agent based emailing architecture that can block spam mail, while at the same time approve certified mail. This architecture can be accelerated by synergistic utilization of digital signature and electronic document interchange.

• Proceedings of the KAIS Fall Conference
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• 2003.11a
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• pp.28-34
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• 2003

Deleting unsolicited email, popularly known as spam mail, is an annoying task for Internet users. Moreover, spam mail causes a variety of social problems. At present, legal restrictions cannot eradicate spam senders. As a result many technical methods to eliminate spam mail such as spam filtering and online stamps have been introduced. However, the process of blocking spam mail can inadvertently result in suspension of indispensable or beneficial communication. In this paper, we propose a certificate and agent based emailing architecture that can block spam mail, while at the same time approve certified mail. This architecture can be accelerated by synergistic utilization of digital signature and electronic document interchange.

• Korean Journal of Oriental Medicine
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• v.13 no.2 s.20
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• pp.127-133
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• 2007

Objectives : This study were aimed to estimate the needs for clinical research educational program development focused on oriental medicine. Methods : Department Medical Research of Korea Institute of Oriental Medicine surveyed 204 certified subjects in total by using web-based questionnaires through e-mail from Jan. 17th to Jan. 31th, 2007. Reply from 62 on-line correspondents were collected and statistically analyzed. Results : The number of clinical trial involving oriental medicine continues to increase. According to the survey, many Issues were raised as problems such as difficulty of recruitment, lack of fund and lack of stepped program. Emphasized issues were clinical research methodologies, development of protocols and case report form (CRF), and Regulations including Institutional Review Boards (IRBs) in these three consecutive education training program. Conclusion : The results of this study may contribute to the development of an educational program for oriental medicine, a program that should be taken into consideration for developing practical items, such as, problem-based learnings which reflects participants' actual needs in their works. Also this report be used for future strategy plans and execution of training program for oriental medical clinical trial.

• Journal of Hospice and Palliative Care
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• v.17 no.4
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• pp.259-269
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• 2014

Purpose: This preliminary study is aimed at developing standardized tools for psycho-social assessment of patients in needs for hospice/palliative care. To accomplish the purpose, investigators examined effects of perceptions of social workers on the importance of psycho-social domains of assessment in hospice/palliative care settings. Moreover, investigators paid attention to variances of perceptions of social workers' along with types of institution and credentials of those family settings. Methods: A form of questionnaire was first explored from an initial interview assessment of 10 government-certified hospice care providers and a literature review, second constructed with eight domains and 80 items, and sent by e-mail to 55 institutions and hospitals providing hospice/palliative cares in Korea. Lastly, a total of 31 agencies returned with a completed responses and consent form (56% response rate). SPSS program (version 18.0) was used for data analysis. Results: Study found that social workers perceived patients' family background (m=4.53, 5-point scale) as the most important assessment domain, whereas economic conditions (4.06 point) the least important. Social workers' perception varied by credentials (i.e., license types, training, full-time position, types of care facility). Conclusion: Based upon study findings, investigators can conclude strong needs for developing a assessment tool that measures multiple domains (i.e., psychological, social and ecological aspects) of patients. A standardized assessment tool should be structured with 2 axis (center/core and expanded/peripheral) and tailored for institution type. Second, professional trainings must be provided by strengthening legal institutionalization and fostering qualified social workers with full responsibilities of hospice and palliative care patients.