• Proceedings of the Korea Multimedia Society Conference
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• 2003.05b
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• pp.45-48
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• 2003

Ad hoc network는 무선 노드들의 집합으로서 어떤 인프라스트럭처 도움 없이 그들 서로가 multi-hop 경로를 통해 통신한다. 네트워크를 구성하는 노드들의 움직임이 빈번히 발생하기 때문에 클러스터간 노드들의 재 가입이 계속되므로 네트워크의 안정성을 유지하기 어렵다. 그러므로 최대한 네트워크 토폴로지의 안정성을 유지하는 것이 필요하다. 본 논문에서는 ad hoc network를 구성하는 노드들을 클러스터로 형성한 후 제한된 broadcast 메커니즘을 이용하여 네트워크의 제어 메시지 flooding 수를 줄이는 효율적인 라우팅 방법을 제안한다.

• Proceedings of the Korea Multimedia Society Conference
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• 2004.05a
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• pp.433-437
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• 2004

지오멀티캐스트는 특별한 지역의존 멀티캐스트 기술이며, 여기서 메시지는 특별한 지역 내에 있는 특별한 사용자 그룹들에게 멀티캐스트 된다. 본 논문에서는 모바일 ad-hoc 네트워크에서 효율적인 비용과 높은 메시지 전송률을 가지는 지오멀티캐스트 구조들과 지오멀티캐스트 서비스를 지원하기 위해서 사용되는 방법들의 성능을 평가하기 위한 구조를 정의하고 제안한다. 이러한 성능평가 구조에 기초하여 제안된 지오멀티캐스트 방법 및 프로토콜들의 성능을 평가하고 이를 기반으로 하여 여러 가지 디자인 및 동작 파라미터들의 영향에 관하여 고찰 점검한다.

• Journal of Internet Computing and Services
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• v.7 no.6
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• pp.175-183
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• 2006

An ad-hoc network is a group of mobile nodes acting as routers. The of hoc node has a precondition of mobility, allowing path to be easily disconnected when transmitting data, thereby increasing network overhead. However, most of hoc routing protocols set up the path based only on the number of hops without considering other practical factors. Here we consider a path with the least substantial number of transmission (SNT) from source to destination based on reliabilities of links. This includes retransmissions due to unreliable links. In this paper, an efficient ad-hoc link reliability based routing (PU) protocol suitable for mobile ah-hoc network in terms of SNT, is proposed. The network overhead and data transmission delay ore reduced, by considering both ad-hoc link reliability and the number of hops. Our empirical performance evaluation comparing to AODV (8) shows that the enhancement is up to about 31% for SNT depending upon the mobility of nodes.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.05a
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• pp.271-276
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• 2008

The intrusion detection system is one of the active fields of research in wireless networks. Intrusion detection in wireless mobile Ad hoc network is challenging because the network topologies is dynamic, lack centralization and are vulnerable to attacks. This paper is about the effective enhancement of the IDS technique that is being implemented in the mobile ad hoc network and deals with security and vulnerabilities issues which results in the better performance and detection of the intrusion.

• Proceedings of the Korean Information Science Society Conference
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• 2006.06d
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• pp.298-300
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• 2006

Ad-hoc 지오캐스팅 프로토콜 목적은 특별한 지오캐스팅영역(Geocasting region)에 위치한 노드들의 그룹에 패킷데이터(Geo-packet)를 전송하는 것이다. 본 논문에서는 Ad-hoc 기반의 이동네트워크 환경에서 지오캐스트 서비스를 지원하는 기존 연구의 데이터 전송경로의 비 최적화, 빈번한 지오캐스트 전송 트리의 재구성으로 인한 오버헤드(Overhead), 서비스 단절의 문제를 해결하기 위해 이동 형태 기반의 가변 지오캐스팅 기법을 제안한다. 가변 지오캐스팅 기법은 서비스 범위를 목적지 노드의 이동성(Mobility)에 따라 가변적으로 설정하고 자원예약 기법과 다양한 실험을 통해 본 논문에서 제안된 지오캐스트 기법을 성능 평가하였다.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.8 no.3
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• pp.25-33
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• 2008

In this paper, the transmit power minimization for Poisson distributed wireless ad-hoc relay networks in Rayleigh fading channels is considered. We investigate two power allocation methods one is a minimum power allocation (MPA) strategy and the other is an equal outage power allocation (EOPA) strategy. We analyze the total transmit power of two allocation methods under the given end-to-end outage probability constraint. Our results show that the MPA achieves more power saving than EOPA, and the power saving is more significant as the number of relay nodes increases.

• Proceedings of the IEEK Conference
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• 2004.06a
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• pp.119-122
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• 2004

This mobile oriented Ad-hoc network yet steps on development level, related issues and standardization are progressing. This paper presented ad-hoc network's overview and overall property, followed by routing scheme that must be setup for communication between each nodes. Among several routing scheme proposed for standardization, ZRP that is foaled by this paper, is hybrid type algorithm, and only includes advantages of others This paper presented running process and implementation method, result that is made from network simulation, shows analysis of each parameter values's change. Each parameters changed with many differences according to Zone radius and communication node's location from simualtion that was performed changing a number of nodes and a velocity of nodes.

• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.1067-1070
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• 2005

In this paper, we propose the address allocation algorithm in hybrid Mobile ad-hoc network (MANET). Most of proposed address autoconfiguration algorithms are node based. Node based address autoconfiguration algorithms are inefficient. Because the node based algorithms waste bandwidth and consume much battery in mobile ad-hoc networks. we present the address allocation algorithm using internet gateway based address autoconfiguration by modifing the IPv6 stateless address autoconfiguration protocol. We use the network simulator NS-2 in our experiments. The simulation result shows reducing network traffic and saving battery.

• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.7-10
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• 2005

Ad hoc MAC protocols using directional antennas can be used to improve the network capacity. Directional antennas have a Deafness problem and decrease throughput of the network caused by increasing backoff duration. Dual channel protocols have been proposed to mitigate the Deafness and hidden node problems. In this paper, we propose a dual channel MAC protocol using a directional antenna to mitigate the Deafness problem and increase the network capacity. The performance of the proposed Ad hoc MAC protocol is confirmed by computer simulations using Qualnet ver. 3.8 simulator.

• IEMEK Journal of Embedded Systems and Applications
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• v.8 no.6
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• pp.329-337
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• 2013

In multihop routed ad hoc networks, the conventional store-and-forward delivery has been used. However, we may ask a question: "Is the store-and-forward delivery still the best?" This paper presents a pipeline-through MAC (PT-MAC) protocol for ad hoc networks, in which nodes have two 3-channel interfaces in order to use limited radio resources efficiently and improve network performance. The proposed protocol reduces end-to-end delay significantly in multihop routed transmission by exploiting a novel pipeline-through technique rather than using the conventional store-and-forward. This results in improved network performance without increasing control overhead. Our extensive performance study shows that the proposed PT-MAC shows 20-40 percent shorter end-to-end delay and 25-55 percent better goodput compared to the IEEE 802.11 DCF with two 3-channel interfaces.