• Journal of the Korea Institute of Information Security & Cryptology
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• v.13 no.2
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• pp.3-11
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• 2003

Proxy signatures are signature schemes in which an original signer delegates her signing capability to a proxy entity, who signs a message on behalf of the original signer. In this paper we propose the ID-based proxy signature schemes using a bilinear map. In the previous R-based proxy signature scheme, the proxy signer can misuse the right of the signing capacity and the public key directory is required. However, by inserting the warrant information such as the identity of the proxy signer and the limit of the signing capacity to the proxy signature, our scheme can prevent the misuse of the proxy key pair by the proxy signer and does not require a public key certificate. Furthermore, our scheme dose not need a secure channel to deliver the warrant. Consequently, the proposed scheme is more efficient and useful than the previous proxy signature schemes.

• Proceedings of the Korea Multimedia Society Conference
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• 2003.05b
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• pp.219-223
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• 2003

디지털 서명과 암호화를 동시에 수행할 수 있는 Signcryption 방식이 Zheng에 의해 제안되었다[1]. 그 후, 서명과 암호화에 요구되는 작업을 상대적으로 성능이 뛰어난 서버에 의뢰 가능하도록 하는 Proxy-Signcryption을 이동통신 환경에 적합하도록 개선한 방식이 제안되었다[2]. 그러나 개선 방식은 효율성과 forword secrecy는 제공하지만 대리자의 부정은 방지할 수 없어 문제가 발생할 수 있다. 따라서 본 논문에서는 대리자가 부정하였을 경우 대리자의 개인키가 노출되도록 한 안전한 Proxy-Signcryption 방식을 제안한다.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.10 no.2
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• pp.43-54
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• 2000

C. Gamage 등은 M. Mambo 의 대리 서명 방시과 Y. Zheng의 signcryption 방식을 이용하여 사용자가 상대 적으로 계산 능력이 뛰어난 서버에 의존하여 암호화 및 서명을 생성할 수 있는 proxy-signcryption 방식을 제안하였다 그러나 그들이 제안한 방식을 실제 응용에 적용할 경우 사용자가 proxy agent를 대신하여 정당한 proxy-signcryption을 생성할 수 있을 뿐만아니라 자신이 전송한 메시지에 대해 부인하는 경우 리를 판단할 수 없으므로 proxy agent를 보호 할 수 없다는 문제점이 있다 따라서 본 논문에서는 대리인 보호형 대리 서명 방식과 N. Asokan 의 S3(Server Supported Signnatures)를 이용하여 proxy agent를 보호할 수 있고 송신자 부인 봉쇄를 제공하여 실제 응용에 적용할 수 있는 proxy-signcryption 방식을 제안하고자 한다. 또한 본 논문에서 제안하는 proxy-signcryption 방식은 한국형 디지털 서명 표준안인 KCDSA(Korean Certificate-based Digital Signature Algorithm)를 이용한다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.3
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• pp.549-555
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• 2007

A digital signature scheme provides integrity of the document, authentication and non-repudiation of a signer. Usually the key for digital signature is stored in hard disk or removal disk storage. The drawback of this approach is that the signer can let the agent to sign instead of the signer by providing the key information. It can be abused in applications such as electronic election. In this paper, we propose the undeniable biometric digital multi-signature scheme suitable for applications where the signer should not make an agent sign instead of himself/herself. The undeniable multi-signature scheme requires many signers and only the designated user can confirm the authenticity of multi-signature. The proposed scheme satisfies undeniable property and it is secure against active attacks such as modification and denial of the multi-signature by signers. As the key is generated through the signer's fingerprint image, it's also secure against signing by an agent.

• Korean Business Review
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• v.13
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• pp.207-221
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• 2000

In this era of changing system, we may learn lesson from newly developed Uniform Electronic Transation Act(UETA) in 1999. Korea has its counterpart as the Basic Electronic Transaction Act and Electronic Signature Act made by 1999. While UETA stresses on transaction law between individuals, that of Korean stresses on the role of government in electronic transaction. Both laws have the common definitions as electronic record, electronic signature, however, UETA has its own definitions such as automated transaction, computer program, electronic agent, information, information processing system, and security procedure. Especially, transferable record in section 16 is one of the most unique concept which Korean law does not provide. Korean government is planning to introduce electronic note in the near future, which will make unprecedented reform in Korean financial industry. Since Korean law does not have such a concept as electronic note, revision of the law is expected soon. Korean law has its specialty which puts stress on cyber mall, authentication agency, and consumer protection. In U.S., the interpretation of law by court is important when they have disputes according to common law traditon. Studies on cases on disputes in U.S. is needed most for Korean application.

• The Korean Journal of Air & Space Law and Policy
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• v.23 no.2
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• pp.67-92
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• 2008

The purpose of this paper is to research the requirements and effect of the document of carriage in respect of the carriage of cargo by air under the Montreal Convention of 1999, IATA Conditions of Carriage for Cargo, and the judicial precedents of Korea and foreign countries. Under the Article 4 of Montreal Convention, in respect of the carriage of cargo, an air waybill shall be delivered. If any other means which preserves a record of the carriage are used, the carrier shall, if so requested by the consignor, deliver to the consignor a cargo receipt. Under the Article 7 of Montreal convention, the air waybill shall be made out by the consignor. If, at the request of the consignor, the carrier makes it out, the carrier shall be deemed to have done so on behalf of the consignor. The air waybill shall be made out in three original parts. The first part shall be marked "for the carrier", and shall be signed by the consignor. The second part shall be marked "for the consignee", and shall be signed by the consignor and by the carrier. The third part shall be signed by the carrier who shall hand it to the consignor after the goods have been accepted. Under the Article 5 of Montreal Convention, the air waybill or the cargo receipt shall include (a) an indication of the places of departure and destination, (b) an indication of at least one agreed stopping place, (c) an indication of the weight of the consignment. Under the Article 10 of Montreal Convention, the consignor shall indemnify the carrier against all damages suffered by the carrier or any other person to whom the carrier is liable, by reason of the irregularity, incorrectness or incompleteness of the particulars and statement furnished by the consignor or on its behalf. Under the Article 9 of Montreal Convention, non-compliance with the Article 4 to 8 of Montreal Convention shall not affect the existence of the validity of the contract, which shall be subject to the rules of Montreal Convention including those relating to limitation of liability. The air waybill is not a document of title or negotiable instrument. Under the Article 11 of Montreal Convention, the air waybill or cargo receipt is prima facie evidence of the conclusion of the contract, of the acceptance of the cargo and of the conditions of carriage. Under the Article 12 of Montreal Convention, if the carrier carries out the instructions of the consignor for the disposition of the cargo without requiring the production of the part of the air waybill or the cargo receipt, the carrier will be liable, for any damage which may be accused thereby to any person who is lawfully in possession of that part of the air waybill or the cargo receipt. According to the precedent of Korea Supreme Court sentenced on 22 July 2004, the freight forwarder as carrier was not liable for the illegal delivery of cargo to the notify party (actual importer) on the air waybill by the operator of the bonded warehouse because the freighter did not designate the boned warehouse and did not hold the position of employer to the operator of the bonded warehouse. In conclusion, as the Korea Customs Authorities will drive the e-Freight project for the carriage of cargo by air, the carrier and freight forwarder should pay attention to the requirements and legal effect of the electronic documentation of the carriage of cargo by air.