• Journal of Communications and Networks
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• 제15권1호
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• pp.1-7
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• 2013

Most of the provably-secure proxy signature schemes rely on the average-case hardness problems such as the integer factorization problems and the discrete logarithm problems. Therefore, those schemes are insecure to quantum analysis algorithms, since there exist quantum algorithms efficiently solving the factorization and logarithm problems. To make secure proxy signature schemes against quantum analysis, some lattice-based proxy signature schemes are suggested. However, none of the suggested lattice-based proxy signature schemes is proxy-protected in the adaptive security model. In the paper, we propose a provably-secure ID-based proxy signature scheme based on the lattice problems. Our scheme is proxy-protected in the adaptive security model.

• 정보보호학회논문지
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• 제15권2호
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• pp.65-72
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• 2005

최근 Zhou, Cao 그리고 Lu는 강한 위조 불가능을 만족하는 RSA와 소인수 분해 문제 기반의 세 가지 대리서명기법을 제안하면서 각각의 대리서명 기법들이 랜덤 오라클 모델하에서 증명가능한 안전성을 제공한다는 주장을 하였다. 본 논문에서는 이 기법들이 원 서명자로부터 위임받지 않은 사용자도 유효한 대리서명을 생성할 수 있게 한다는 점을 보임으로써 대리서명이 만족해야 하는 기본적인 안전성을 만족하지 않는다는 것을 보인다.

• 한국정보처리학회논문지
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• 제6권3호
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• pp.641-653
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• 1999

The paper is design and implementation of the system to support security communication between a Web Browser and a CGI program by a Web Server using PKI(Public Key Infrastructure. This system uses GSS(Generic Security Service)-API to communicate with PKI, offers a Web user a Client Proxy, and offers a CGI developer there library functions related with security. TLS(Transport Layer Security) supports security communication between a Web Browser and a Web Server, but the system supports security communication between a Web Browser and a CGI program as the protected data received from a Client Proxy are sent to a CGI program, and the CGI program decrypts the data using the library functions supported by this system.

• Journal of Communications and Networks
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• 제13권5호
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• pp.518-524
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• 2011

A high assurance IP encryption (HAIPE) compliant protocol accelerator is proposed for military networks consisting of red (or classified) networks and black (or unclassified) networks. The boundary between red and black sides is assumed to be protected via a HAIPE device. However, the IP layer encryption introduces challenges for bandwidth on demand satellite communication. The problems experienced by transmission control protocol (TCP) over satellites are well understood: While standard modems (on the black side) employ TCP performance enhancing proxy (PEP) which has been shown to work well, the HAIPE encryption of TCP headers renders the onboard modem's PEP ineffective. This is attributed to the fact that under the bandwidth-on-demand environment, PEP must use traditional TCP mechanisms such as slow start to probe for the available bandwidth of the link (which eliminates the usefulness of the PEP). Most implementations recommend disabling the PEP when a HAIPE device is used. In this paper, we propose a novel solution, namely broadband HAIPE-embeddable satellite communications terminal (BHeST), which utilizes dynamic network performance enhancement algorithms for high latency bandwidth-on-demand satellite links protected by HAIPE. By moving the PEP into the red network and exploiting the explicit congestion notification bypass mechanism allowed by the latest HAIPE standard, we have been able to regain PEP's desired network enhancement that was lost due to HAIPE encryption (even though the idea of deploying PEP at the modem side is not new). Our BHeST solution employs direct video broadcast-return channel service (DVB-RCS), an open standard as a means of providing bandwidth-on-demand satellite links. Another issue we address is the estimation of current satellite bandwidth allocated to a remote terminal which is not available in DVBRCS. Simulation results show that the improvement of our solution over FIX PEP is significant and could reach up to 100%. The improvement over the original TCP is even more (up to 500% for certain configurations).

• 한국중재학회지:중재연구
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• 제21권2호
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• pp.113-131
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• 2011

Recently, the Internet Corporation for Assigned Names and Numbers (ICANN) announced the expansion of the number of generic top-level domains (gTLDs) beyond the current 22 gTLDs, and the gTLD Applicant Guidebook for ICANN's new gTLD program is now under consideration for approval. ICANN also introduces a "Trademark Clearinghouse" and the "Uniform Rapid Suspension (URS)" procedure to protect trademarks and expedite dispute resolution and save costs. The Trademark Clearinghouse is a central repository for information to be authenticated, stored and disseminated, pertaining to the rights of the trademark holders. Trademark holders would voluntarily provide data of their trademarks from all over the world, and it would assist a trademark watch service provided by the new gTLD registry for trademark holders and potential domain name registrants. The URS is a part of the new gTLD dispute resolution mechanisms created by ICANN to resolve cybersquatting disputes. A complainant in a URS proceeding must establish three elements that are very similar to the existing UDRP to succeed, but supposedly more expedited and cost efficient. Since the URS provides that it only protects court validated and registered trademarks, it is not clear whether unregistered marks used in commerce are protected under the URS. The URS escalates the complainant's burden of proof from a preponderance of evidence standard under the UDRP to a clear and convincing evidence standard. The notices to a respondent shall be sufficient if the URS Provider sends the notice of Complaint to the addresses listed in the Whois contact information. As registrants who wish to conceal their true identity often subscribe to the privacy/proxy service and the complainant's high rate of success in the UDRP proceeding is relevant to the respondents' default rate, the URS's simple notice requirement would deprive respondents of a fair opportunity to assert their rights over the disputed domain names.

• 한국통신학회논문지
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• 제35권2B호
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• pp.302-312
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• 2010

IPTV 서비스는 인터넷 망을 통해 가입자가 원하는 양방향 멀티미디어 콘텐츠를 제공하는 통신 방송 융합 서비스이다. 그러나 현재 개발되고 있는 CAS 기반의 IPTV 서비스는 댁내에 존재하는 IPTV 서비스 가용 단말들로 방송 콘텐츠를 재분배하는 과정에서 셋탑박스와 IPTV 서비스 가용 단말간의 보안, 댁외로 이동하는 IPTV 서비스 가입자의 이동성 지원을 위한 보안을 제공하지 못한다. 본 논문에서는 댁내 셋탑박스에서 이동 단말로 안전하게 콘텐츠를 재분배하기 위한 인증 프로토콜과 댁외로 이동한 사용자 단말의 네트워크 접속 인증 및 서비스 접속인증을 위한 인증 프로토콜을 제안 한다. 제안 기법은 대리 서명 기법을 적용하여 기존 CAS 시스템을 통해 전달되는 콘텐츠를 재암호화 과정 없이 전달할 수 있다. 그리고 STB가 인증 서버를 대신하여 발급한 서명을 이용하여 댁외로 이동한 사용자 단말에 대한 네트워크 접속 인증과 IPTV 서비스 접속 인증을 동시에 수행할 수 있다. 또한 기존 보안 기술들과의 비교 분석을 통해 인증 프로토콜 적용에 따른 전체 통신 오버헤드 및 연산시간이 감소함을 보였다.

• 한국중재학회지:중재연구
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• 제17권2호
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• pp.167-187
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• 2007

As Korea has reached a free trade agreement with the United States of America, it is required to provide an appropriate procedure to ".kr" domain name disputes based on the principles established in the Uniform Domain Name Dispute Resolution Policy(UDRP). Currently, Internet address Dispute Resolution Committee(IDRC) established under Article 16 of the Act on Internet Address Resources provides the dispute resolution proceedings to resolve ".kr" domain name disputes. While the IDRC's proceeding is similar to the UDRP administrative proceeding in procedural aspects, the Domain Name Dispute Mediation Policy that is established by the IDRC and that applies to disputes involving ".kr" domain names is very different from the UDRP for generic Top Level Domain (gTLD) in substantial aspects. Under the Korea-U.S. Free Trade Agreement(KORUS FTA), it is expected that either the Domain Name Dispute Mediation Policy to be amended to adopt the UDRP or the IDRC to examine the Domain Name Dispute Mediation Policy in order to harmonize it with the principles established in the UDRP. It is a common practice of cybersquatters to warehouse a number of domain names without any active use of these domain names after their registration. The Domain Name Dispute Mediation Policy provides that the complainant may request to transfer or delete the registration of the disputed domain name if the registrant registered, holds or uses the disputed domain name in bad faith. This provision lifts the complainant's burden of proof to show the respondent's bad faith because the complainant is only required to prove one of the three bad faiths which are registration in bad faith, holding in bad faith, or use in bad faith. The aforementioned resolution procedure is different from the UDRP regime which requires the complainant, in compliance with paragraph 4(b) of the UDRP, to prove that the disputed domain name has been registered in bad faith and is being used in bad faith. Therefore, the complainant carries heavy burden of proof under the UDRP. The IDRC should deny the complaint if the respondent has legitimate rights or interests in the domain names. Under the UDRP, the complainant must show that the respondent has no rights or legitimate interests in the disputed domain name. The UDRP sets out three illustrative circumstances, any one of which if proved by the respondent, shall be evidence of the respondent's rights to or legitimate interests in the domain name. As the Domain Name Dispute Mediation Policy provides only a general provision regarding the respondent's legitimate rights or interests, the respondent can be placed in a very week foundation to be protected under the Policy. It is therefore recommended for the IDRC to adopt the three UDRP circumstances to guide how the respondent can demonstrate his/her legitimate rights or interests in the disputed domain name. In accordance with the KORUS FTA, the Korean Government is required to provide online publication to a reliable and accurate database of contact information concerning domain name registrants. Cybersquatters often provide inaccurate contact information or willfully conceal their identity to avoid objection by trademark owners. It may cause unnecessary and unwarranted delay of the administrative proceedings. The respondent may loss the opportunity to assert his/her rights or legitimate interests in the domain name due to inability to submit the response effectively and timely. The respondent could breach a registration agreement with a registrar which requires the registrant to submit and update accurate contact information. The respondent who is reluctant to disclose his/her contact information on the Internet citing for privacy rights and protection. This is however debatable as the respondent may use the proxy registration service provided by the registrar to protect the respondent's privacy.