• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.6
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• pp.109-116
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• 2007

The lack of load-balancing functionality in most existing ad hoc routing protocols often causes congestion resulting in bad performance and short lifetime of participating nodes. We present an auxiliary scheme for reactive routing protocols to discover an unloaded route, thereby decreasing possibility of congestion. The scheme allows an intermediate node to determine whether to be a relaying node for a newly constructed route autonomously based on the occupancy of its queue. Thus the scheme does not require network-wide load information. Simulation results show that the proposed scheme distributes traffic load well.

• Journal of KIISE:Information Networking
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• v.31 no.5
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• pp.519-531
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• 2004

Ad-hoc networks are temporary wireless systems composed of mobile nodes without any fixed infrastructure. The life time of each node in the ad-hoc network significantly affects the life time of whole ad-hoc network. A node which drained out its battery may incur the partition of whole network in some network topology The life time of each node depends on the battery capacity of each node. Therefore if all mobile nodes in the network live evenly long, the life time of the network will be longer. In this paper, we propose Power-Aware Dynamic Source Routing (PADSR) which selects the best path to make the life time of the network be longer. In PADSR, when a source node finds a path to the destination node, it selects the best path that makes nodes in the network live evenly long. To find the best path, PADSR considers the consumption of transmission energy and residual battery capacity of nodes upon the path. Consequently the network lives longer if we use PADSR.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.3
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• pp.593-600
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• 2007

In this paper, we composed several road network and evaluated the network for the performance of the network with protocols. The protocols we applied were the MANET routing protocols such as AODV(Ad-hoc On-Demand Distance Vector) and DSR(Dynamic Source Routing) protocols. Generally, the AODV performs better than the DSR. However, in my ad-hoc vehicular network, the performance of the DSR is the better than the AODV when there are more vehicles in the road environment than there are the less vehicles. For the simulation, we composed 4-lane road with vehicles and simulated in the OPNET.

• Proceedings of the Korea Multimedia Society Conference
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• 2001.06a
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• pp.232-235
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• 2001

최근 노트북 컴퓨터나 PDA(Personal Digital Assistants)와 칼은 개인 휴대용 통신장비의 사용이 급속도로 증가하고 있다. 매우 동적인 상황에서 이러한 장비들간의 통신은 우선 Ad-Hoc망의 발전을 초래하였다. Mobile Ad Hoc Network(MANET)은 전통적인 유선 환경과는 달리 무선 송·수신 장치를 가진 무선 이동노드의 집합이며, 동적인 토폴로지, 한정된 대역폭의 가변적인 링크용량, 한정된 에너지라는 특성을 갖는다. 본 논문에서는 Ad-Hoc 라우팅 프로토콜 중 Temporally-Ordered Routing Algorithm(Tora)상에서 데이터 트래픽의 성능을 분석하였다. 인터넷 데이터 트래픽 소스로는 CBR(Constant Bit Rate)를 사용하였고, 모의실험 결과 망의 이동성은 라우팅 프로토콜의 트래픽 성능을 분석하는 데 있어서 중요한 요소가 된다는 것을 알 수 있었다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.05a
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• pp.117-120
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• 2002

Bluetooth uses baseband of 2.4G ISM and composes radio Ad Hoc network based on Ad Hoc wireless connectivity which it used low power and low complexity solution. Bluetooth designed as can play detect, connect, discover service by surrounding other device even if users do not get acquainted all to Bluetooth. This paper operate wish to recognize mobility to routing algorithm how communication method and radio network in Bluetooth.

• The KIPS Transactions:PartC
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• v.8C no.4
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• pp.459-468
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• 2001

실제적인 이동 Ad Hoc 망에서는 단말의 비대칭성이나 무선환경 특성으로 인해 단방향 링크가 존재할 수 있다. 그러나 현재 Zone 라우팅 프로토콜이외의 기존의 이동 Ad Hoc 라우팅 프로토콜은 양방향 링크들만을 지원하도록 구현되어 있다. 따라서 본 논문에서는 가장 대표적인 라우팅 프로토콜인 DSR(Dynamic Source Routing) 프로토콜이 단방향 링크를 포함하는 이동 Ad Hoc 망에서 구동될 수 있도록 동적 소스 라우팅을 이용한 새로운 단방향 라우팅 프로토콜을 제안한다. 단방향 링크 상에서 효율적으로 구동하기 위해서 제안한 단방향 라우팅 프로토콜은 새로운 경로발견 및 경로유지 방법을 사용하였다. 성능평가를 위해서 미국 버클리 대학의 NS-2 시뮬레이터 프로그램에 제안한 내용을 코드로 삽입시켰으며, 성능평가 파라미터를 얻기 위해 카네기멜론 대학에서 제공한 이동 패턴파일과 연결 패턴파일을 조합하여 사용하였다. 성능평가 항목으로 데이터수신율 및 평균경로 설정시간을 고려하였으며, 제안된 3가지 경로설정 방식들에 대해 비교·평가하였다.

• Journal of the Korea Society of Computer and Information
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• v.11 no.6 s.44
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• pp.221-226
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• 2006

An Ad hoc network, differently from wired networks, is a self organized network of mobile nodes in wireless environments. In this kind of routing and operation environments. link breaks occur frequently. Knowing positions of nodes may prevent or recover this type of phenomenon. Typically, GPS is used to detect position of nodes but high cost and complexity of construction limit applications. In this paper, we propose and design a method of construction nodes' position map using only information of all nodes without GPS. The proposed method complements and overcomes previous system with software solutions. Hence, construction and operation are simple, and can decrease cost of construction expenses.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.4
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• pp.1001-1008
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• 2015

Mobile Ad hoc Network(MANET) consists of a node that has mobility. In MANET, the node has routing, the node builds a network of their own, no dependent infrastructure. Topology are exchanged due to node mobility in MANET. For reducing the change of topology, hierarchical network algorithm has been investigated. In hierarchical network, cluster member node communicates through cluster head node. When the load-balancing of cluster head node is exceed, assigned cluster member node can't communicate with base station. To solve this problem, we proposed Load Tolerance algorithm. The proposed algorithm, when cluster member node can't send a message by cluster head node that exceed load-balancing, then the cluster member node sends a message by selected load tolerance node. Through a simulation, the proposed algorithm improves packet delivery ratio in cluster routing.

• Journal of IKEEE
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• v.7 no.1 s.12
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• pp.63-71
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• 2003

In this paper, we propose an DSR(Dynamic Source Routing) protocol to support QoS for reliable data transmission in the mobile ad-hoc network. The proposed algorithm uses DSR protocol to support QoS as its basic routing protocol, and uses the nodes which are between source and destination nodes as key QoS support. Because of moving nodes there is some problem that is restricted reliable data transmission. For solve this problem, source node set up the QoS link with destination node. The nodes that are located at QoS link and find out loss of transmission path save the transmitting data packets. Those search a new transmission path to destination node and transmit the saved data packet to destination node. As the result of evaluation, we found the proposed QoS network guaranteed reliable data transmission with almost 100% data reception rate for slowly moving mobile ad-hoc network and with more 96% data reception rate, which is improvement of 3.7737% reception rate compared with none QoS network, for continuously fast moving mobile ad-hoc network.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2014.05a
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• pp.781-783
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• 2014

Mobile ad hoc network(MANET) consists of node that has mobility. MANET has increased overhead that caused by frequent topology changes. For reducing overhead, hierarchical network that communicates through cluster head node has been researched. When traffic is concentrated on cluster head node, cluster member node can't send message. To solve this problem, we proposed Step Parent algorithm. Proposed algorithm, cluster member node checks traffic of cluster head node using route path of other cluster head node in efficient coverage area. When cluster head node has increased traffic, cluster member node make a new route path by route path by routing path to another cluster head node. So cluster member node sends a message to destination node, we check improving delivery ratio.