• Proceedings of the Korea Information Processing Society Conference
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• 2001.10b
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• pp.1359-1362
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• 2001

Ad-hoc 망은 기존의 유선망이나 중앙집중화된 관리의 도움 없이 무선이동단말 스스로가 동적으로 구성하는 망이다. 현재 ad hoc망에서의 라우팅을 위해 제시된 on-demand 방식의 라우팅 프로토콜은 경로발견을 위해 blind flooding을 수행하며 이는 프로토콜의 효율성을 저해하고 있다. 본 논문에서는 이러한 blind flooding의 문제점을 개선한 수 있는 방법으로 2-hop거리의 이웃노드들에 대한 정보와 threshold factor를 이용하여 선택적으로 flooding을 수행함으로써 라우팅 오버헤드를 줄일 수 있는 방법을 제시한다.

• Proceedings of the Korean Information Science Society Conference
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• 2004.10c
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• pp.295-297
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• 2004

무선 ad-hoc 네트워크란 기반 시설의 도움 없이 노드들 간의 수평적인 통신을 제공하는 임시적인 네트워크이다. 이러한 네트워크 환경에서는 각 노드의 네트워크 창가 밀 이탈이 동적으로 가능하다. 현재 이러한 환경에서 높은 이동성을 지원하는 동시에 라우팅 오버헤드를 최소화하는 연구가 활발히 진행되고 있다. 기존에 제안된 무선 ad-hoc 라우팅 프로토콜들은 부하균형 메커니즘을 지원하지 않으므로 특정 노드에 많은 부하가 발생할 수 있다. 이로 인해 종단 간 지연시간이 길어지며 네트워크의 신뢰성이 낮아질 수 있다. 본 논문에서는 이러한 문제의 해결을 위해 각 노드가 자신의 부하를 측정하고, 경로 요청 시 노드의 부하 정보를 이용해서 부하가 적은 경로를 선택하도록 한다. 또한 데이터 전송 중에 해당 경로의 부하를 확인하여, 보조 경로를 이용하거나 새로운 경로를 검색하여 경로의 혼잡을 해결함으로써 종단 간 지연시간 및 네트워크의 신뢰성을 향상시키는 기법을 제안한다. 본 논문에서 제안하는 기법은 특정 노드에 라우팅 오버헤드가 집중되는 것을 방지하며 이로 인해 종단 간 지연시간을 줄이고 네트워크의 신뢰성 을 향상시킨다.

• The KIPS Transactions:PartC
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• v.9C no.5
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• pp.647-654
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• 2002

Ad-hoc networks consist of a set of mobile hosts that communicate using wireless links, without the use of other supporting communication facilities (such as base stations, etc.). Therefore, the topology of an Ad-hoc network frequently changes due to the movement of mobile host, which nay lead to sudden packet loss. Recently, the large amount of research has focused on the routing protocols needed in such an environment. In this paper, TCP Reno, Sack, and Tahoe versions are analysed using DSR protocol which is the representative On-Demand routing protocol in Ad-hoc wireless network. As the result of this simulation, we know that TCP Reno relatively has higher throughput than that of Sack and Tahoe, and TCP Reno has more stable performance than that of TCP Tahoe and Sack, regardless of the speed of mobile node and the size of topology.

• The KIPS Transactions:PartC
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• v.13C no.6 s.109
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• pp.685-690
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• 2006

This paper compares the performance of the unicast routing protocol and the broadcast routing protocol in a small-sized wireless multi-hop network, such as home network. Normally, ad-hoc routing protocols are designed for general wireless multi-hop networks, not being said to be optimized for the small-sized ad hoc network. This paper compares some unicast routing protocols and optimal broadcast routing protocol, and shows the result. The result of the simulation says the broadcast routing protocol shows better performance than the ad-hoc routing protocols in the small-sired wireless multi-hop network. Especially, the result shows that the broadcast protocol has higher packet delivery ratio and lower packet latency than unicast routing protocols

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.19 no.6
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• pp.41-46
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• 2019

In this paper, it is necessary to study the bandwidth and network system for efficient image transmission in the current era of drone imaging, and to design routing protocols to round out and cluster two or more multi-drones. First, we want to construct an ad hoc network to control the multidrone. Several studies are underway for the clustering of drones. The aircraft ad hoc network (FANET) is an important foundation for this research. A number of routing protocols have been proposed to design a FANET, and these routing protocols show different performances in various situations and environments. The routing protocol used to design the FANET is tested using the routing protocol used in the existing mobile ad hoc network (MANET). Therefore, we will use MANET to simulate the routing protocol to be used in the FANET, helping to select the optimal routing protocol for future FANET design. Finally, this paper describes the routing protocols that are mainly used in MANET and suitable for FANET, and the performance comparison of routing protocols, which are mainly used in FANET design.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.8 no.1
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• pp.31-37
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• 2008

In this paper, we propose an entropy-based routing protocol to effectively support both stable route construction and route lifetime in Mobile Ad-hoc Wireless Sensor Networks (MAWSN). The basic idea and feature of the proposed routing protocol are as follows. First, we construct the stable routing routes based on entropy concept using mobility of mobile nodes. Second, we consider a realistic approach, in the points of view of the MAWSN, based on mobile sensor nodes as well as fixed sensor nodes in sensor fields while the conventional research for sensor networks focus on mainly fixed sensor nodes. The performance evaluation of the proposed routing protocol is performed via simulation using OPNET(Optimized Network Engineering Tool) and analysis. The results of the performance evaluation show that the proposed routing protocol can efficiently support both the construction of stable route and route lifetime in mobile ad-hoc wireless networks.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.9
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• pp.1665-1671
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• 2007

Mobile Ad hoc Networks (MANETs) refer to autonomous networks in which wireless data communications are established between multiple nodes in a given coverage area without a base station or centralized administration. Because of node mobility and limited battery life, the network topology may changes frequently. Selecting the most reliable path during route discovery process is important to improve performance in ad-hoc networks. In this study, we proposed an enhanced routing protocol based on AODV by monitoring variation of receiving signal strength. New metric function that consists of node mobility and hops of path is used for routing decision. From extensive experiments by using NS-2, The performance of the proposed routing scheme has been imp개ved by comparison to AODV protocol.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.3
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• pp.486-490
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• 2007

Recently, there have been active research efforts on devising efficient routing algorithms utilizing location information in ad-hoc mobile networks. In this paper, we propose a new method to improve the performance of the widely recognized Location Aided Routing (LAR) algorithm. To this end, we suggest the concept of accessible zone combined with the basic two schemes associated with LAR algorithm. Through the proposed algorithm, we can confine the flooding area within accessible zone, thereby reducing the routing delay.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.8A
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• pp.639-648
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• 2005

A wireless ad-hoc network is a temporal network formed by a collection of wireless mobile nodes without the aid of any existing network infrastructure or centralized ad-ministration. Numerous routing protocols have been developed for changing messages among the nodes in a wireless ad-hoc network. Some multi-path routing protocols have also been proposed to support load balancing and QoS for wireless ad-hoc networks. In this paper, we propose not only an efficient routing algorithm for wireless ad-hoc net-worts but also a protocol that can improve data transmission rate and reduce end-to-end delay. In our protocol, each mobile node need not broadcast routing messages periodically and the mobile node that wants to send data packets initiates route request and route establishment procedure. By simulation, we showed that faster route recovery is possible by maintaining multiple routing paths in each node, and the route maintenance overhead can be reduced by limiting the number of multiple routing paths.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.05a
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• pp.197-200
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• 2011

Many routing protocols have been proposed for low-power and ad-hoc networks where energy awareness and reliability are essential design issues. This paper proposes a dynamic routing protocol for low-power and ad-hoc networks. A dynamic path cost function is defined considering the constraints and characteristics of low-power and ad-hoc networks. The cost function can be applied flexibly depending on the characteristics of the networks. The performance of the proposed method is evaluated using a QualNet network simulator.