• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2004.11a
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• pp.148-148
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• 2004

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2004.07a
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• pp.283-283
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• 2004

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2004.11a
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• pp.146-146
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• 2004

• Bulletin of the Korean Space Science Society
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• 2004.10b
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• pp.351-355
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• 2004

A multibeam switching satellite system technology have started localized development to overcome the limitation of the frequency resource and geostationary orbit existing relay type satellite transponder and the required performance of the spot beam, and looked around the configuration and functions of the multibeam switching satellite communication system. This paper proposed that operation scheme and network control features for service definition, network architecture, transmission method of the natural disaster service network and public communication service network using this system.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2004.07a
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• pp.304-304
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• 2004

• Bulletin of the Korean Space Science Society
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• 2004.10b
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• pp.368-371
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• 2004

ETRI has developed the EQM (Engineering Qualification model) payload system for the communications and broadcasting satellite (CBS) with Korean local companies. This paper describes a series of environmental tests such as vibration, thermal/thermal vacuum, and EMC tests. All the development processes including the design, implementation, integration and workmanship were verified and evaluated by these tests. The results of the functional tests and the compliance to the requirements are also presented. The technologies and heritage obtained from this development will be applied to the development of the payload system for the Korean communication satellite in the near future.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.2986-2988
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• 2000

현재의 네트웍 환경은 다양한 통신 장비와 서비스들의 개발로 망 구성 요소간 이질적인 특성이 증가함에 따라 복잡해지고 어려워진 반면 사용자의 네트웍에 대한 품질 요구는 점점 더 증가하고 있다. 이러한 환경은 고성능의 네트웍 관리시스템과 전문적인 네트웍 진단기술을 필요로 한다. 하지만 기존의 관리시스템들은 네트웍 트래픽 모니터링에 의한 단순 평면적인 통계 기능을 가지고 있을 뿐만 아니라 네트웍 진단 기술 또한 체계화 되지 못하였다. 따라서 본 논문은 전력통신망에서 네트웍 전체를 대상으로 네트웍 성능, 장애 상태를 분석하여 네트웍의 현황을 진단하고 트래픽 특성을 통한 문제자원을 파악한 후 원인과 해결책을 제공하도록 지능적인 네트웍 분석기법을 통한 효과적인 전력통신망 운용 관리 방안을 제시한다.

• Proceedings of the Korea Information Processing Society Conference
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• 2001.04a
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• pp.557-560
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• 2001

전력연구원에서는 기존 사내 통신망 트래픽 분석을 통해 최적의 네트워크 모델을 설계하고 설계된 모델을 기반으로 시뮬레이션을 수행함으로써 향후 트래픽 증가와 수요 현황을 토대로 한 중장기적인 관정에서의 바람직한 네트워크 모델을 제시할 수 있는 방향을 제시하기 위한 연구를 수행하고 있다. 본 논문에서는 해당 연구와 관련하여 도출한 네트워크 설계안와 시뮬레이션 결과에 대해 기술하고 있다.

• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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• 2002.11a
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• pp.81-83
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• 2002

Group signature schemes allow a group member to sign a document on behalf of the group anonymously. In addition, in case of anonymity misuse, a group authority can recover the issuer of a signature. In this paper, we analyze the security of a group signature scheme proposed by Popescu which is a modification of the Tseng-Jan group signature scheme. We show that the scheme can't provide an important requirement of the group signature, unlikability. Thus, other members are allowed to identify whether two signatures have been issued by the same group member or not.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.6B
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• pp.977-983
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• 2010

In mobile and secure military networks, full-meshed IPSec tunnels, which do correspond to not physical links but logical links between each IPSec device and its peer, are required to provide multicast communications. All IPSec devices need support in changing IPSec tunnels by a way of using a multicast group key which is updated dynamically. Tactical terminals, which often constitute a group, need also secure multicast communications in the same group members. Then, the multicast group key is required to be updated dynamically in order to support group members' mobility. This paper presents challenging issues of designing a secure and dynamic group key management of which concept is based on the Diffie-Hellman (DH) key exchange algorithm and key trees. The advantage of our dynamic tree based key management is that it enables the dynamic group members to periodically receive status information from every peer members and effectively update a group key based on dynamically changing environments.