• International Journal of Computer Science & Network Security
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• v.22 no.7
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• pp.13-20
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• 2022

Basically Mobile Ad Hoc Network (MANET) is an autonomous system with the collection of mobile nodes, these nodes are connected to each other by using wireless networks. A mobile ad hoc network poses this quality which makes topology in dynamic manner. As this type of network is Ad Hoc in nature hence it doesn't have fixed infrastructure. If a node wishes to transfer data from source node to a sink node in the network, the data must be passed through intermediate nodes to reach the destination node, hence in this process data packet loss occurs in various MANET protocols. This research study gives a comparison of various Mobile Ad Hoc Network routing protocols like proactive (DSDV) and reactive (AODV, DSR) by using random topology with more intermediate nodes using CBR traffic. Our simulation used 50, 100, and 150 nodes variations to examine the performance of the MANET routing protocols. We compared the performance of DSDV, AODV and DSR, MANET routing protocols with the result of existing protocol using NS-2 environment, on the basis of different performance parameters like Packet Delivery Ratio, average throughput and average end to end delay. Finally we found that our results are better in terms of throughput and packet delivery ratio along with low data loss.

• Journal of KIISE:Information Networking
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• v.35 no.6
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• pp.521-528
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• 2008

Such conventional maritime communication technologies as radio have short some comings in their transmission quality. It can be overcome by wireless channels provided by satellites such as INMARSAT, which nevertheless suffer from the high costs. In this paper, we propose a novel technology resolving the above problems, featuring in the establishment of maritime communication networks with multi-hop structures. The inter vessel and ship-to- shore networks previously modeled after MANET are remodeled by SANET (Ship Ad Hoc Networks) in the present work. Fan-shaped Search Zone Routing (FSR) protocol also is presented, which utilizes not only static geographical information including the locations of ports and the navigations of courses but also the unique characteristics of ships in terms of mobile nodes. The FSR finds the fan-shaped search zone on which the shortest path is located. The performance of LAR protocol is compared with that of FSR in several ways. First, FSR does not make use of a type of control packets as beaconing data, resulting in a full utilization of the bandwidth of the wireless channels. Second, the delivery rate by the FSR is 100% for the fan-shaped search zone includes at least one route between source and destination nodes on its border line, where as that of LAR has been turned out to be 64%. Third, the optimality of routes searched by the FSR is on a 97% level. Of all, the FSR shows a better performance than LAR by about 50%.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.46 no.5
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• pp.139-145
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• 2009

Recently P2P (Peer-to-Peer) networks and applications have been expanded to various field. However, because the construction of P2P network did not influence a underlying network topology or property, it may be inefficient. Especially, this inefficiency is more serious in MANET because MANET has narrow bandwidth and energy constraint. When we use a proactive routing protocol in MANET, we can know hop counts between two nodes. And, we can construct a P2P overlay network using this hop count information. However, In case of using hop count only, we can avoid a interference path selection problem and a zig-zag problem. We propose a method of improving P2P contents distribution using virtual positions. We calculate virtual positions from hop counts using the trigonometry. This method solves a interference path selection problem and a zig-zag problem. This method also allows a P2P network to influence underlying network topology. We adopt this method to a network which uses a virtual geographic routing, a proactive routing protocol, or a reactive routing protocol. We show that our proposed methods improve P2P contents distribution performance over MANET through a simulation.

• Journal of Communications and Networks
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• v.7 no.3
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• pp.325-336
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• 2005

Mobile ad hoc networks (MANET) are composed of moving wireless hosts which, within range of each other, form wireless networks. For communication to occur between hosts that are not within each other's range, routes involving intermediate nodes must be established; however, since the hosts may be in motion, a host that was part of a route may move away from its upstream and downstream partners, thus breaking the route. In this paper, we propose anticipated route maintenance (ARM) protocol with two extensions to route discovery based routing scheme: Extend the route when nodes on a link move apart from each other and they have common neighbor that can be 'inserted' in the path, and shrink route when a node discovers that one of its neighbor which is not the next hop is also on the same route several hops later on. By utilizing only local geographic information (now a part of some route finding algorithms), a host can anticipate its neighbor's departure and, if other hosts are available, choose a host to bridge the gap, keeping the path connected. We present a distributed algorithm that anticipates route failure and performs preventative route maintenance using location information to increase a route lifespan. The benefits are that this reduces the need to find new routes (which is very expensive) and prevents interruptions in service. As the density of nodes increases, the chance to successfully utilize our route maintenance approach increases, and so does the savings. We have compared the performance of two protocols, pure dynamic source routing (DSR) protocol and DSR with ARM. The simulation results show how ARM improves the functionality of DSR by preventing the links in the route from breaking. Packets delivery ratio could be increased using ARM and achieved approximately $\100%$ improvement. The simulations clarify also how ARM shows a noticeable improvement in dropped packets and links stability over DSR, even though there is more traffic and channel overhead in ARM.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.3A
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• pp.221-231
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• 2006

TCP is needed as a transport protocol to provide reliable end-to-end message delivery for MANETs in order to achieve a smooth integration with the fixed Internet. Particularly, TCP has its variants, namely TCP-Reno and TCP-Vegas. However, there has been no research work on extensive performance comparison of TCP-Reno and TCP-Vegas over AODV and OLSR. This paper is the first trial to perform the research by using ns-2 simulator. Through the extensive simulations, we found that which to select among routing protocols is more important than which to select among TCP variants, because the performance difference between TCP-Reno and TCP-Vegas over uy selected routing protocol is not so much outstanding. Particularly, TCP-Vegas relies on an accurate BaseRTT estimation in order to decide the sending rate of a TCP Sender. However, it cannot be directly applied to MANET because a route change makes the Base an used over a Previous Path obsolete. Therefore, we propose a technique for improving the performance of TCP-Vegas by considering the route change, and show the performance improvement through simulation study.

• Proceedings of the Korean Information Science Society Conference
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• 2002.04a
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• pp.127-129
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• 2002

인터넷에는 다른 하드웨어적 특성을 갖는 다양한 형태의 이동노드가 존재한다. 이러한 특성이 무선통신 과정에 반영되어 다양한 문제가 발생한다. 이동 노드로만 구성된 무선 ad-hoc 네트웍은 이와 같은 특성에 큰 영향을 받게 된다. 기존의 ad-hoc 네트웍 라우팅 프로토콜은 목적 노드에 도달하기 위한 경로의 발견과 관리에 연구가 집중되었으며, 최근 이동노드의 특성을 라우팅 과정에 반영하기 위한 연구가 시작되고 있다. 본 논들은 ad-hoc 라우팅 프로토콜에서 이동노드가 갖는 이질적 특성을 라우팅에 반영하고, 이를 AODV 라우팅 프로토콜에 적용하기 위한 메커니즘을 제안한다. 본 메커니즘은 이동노드의 특성을 이용한 Proactive 방식의 노드가 추가되어 일반 이동노드에게 다중 홉의 경로에 대한 패킷 전송을 대신하며 주변 이동 노드에게 다중 홉의 라우팅 정보를 제공한다. Reactive 방식의 노드는 Proactive 방식의 노드를 발전하고 이용하기 위해 기능을 확장하였다. 이를 통하여 안정적인 경로를 선택 할 수 있으며 ad-hoc 네트워크 망의 확장이 가능하다.

• Proceedings of the Korea Multimedia Society Conference
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• 2012.05a
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• pp.89-92
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• 2012

Wireless Mesh Network expanded the capability of the conventional wireless networking by allowing the nodes to operate in proactive mode, reactive mode or the combination of both, the hybrid mode in the multi-hopping nature. By doing so, the links between the nodes become much more robust and reliable because of the number of paths to reach a destination node from a source node can be more than 1 and do not need to rely on the access point (AP) alone to relay the messages. As there may be many possible ways to form an end-to-end link between 2 nodes, the routing security becomes another main concern of the 802.11s protocol. Besides its reliance on the 802.11i for the security measures, 802.11s also includes some new features such as the Mesh Temporal Key (MTK) and the Simultaneous Authentication of Equals (SAE). The authentication and key management (AKM) process of 802.11s were observed in this paper.

• Annual Conference of KIPS
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• 2002.11b
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• pp.1583-1586
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• 2002

본 논문에서는 ad hoc 네트워크에서 사용되는 proactive 라우팅 프로토콜과 reactive 라우팅 프로토콜의 혼합인 hybrid 라우팅 프로토콜에 대해 제안하였다. 본 논문에서는 기존의 hybrid 라우팅 프로토콜이 ZRP와는 달리 Ad hoc 네트워크를 구성하는 노드들 중에 네트워크 서비스를 제공해주는 특별한 노드를 설정하여 라우팅 하는 방법을 제안한다. 이러한 역할을 해주는 특별한 노드를 본 논문에서는 C-Node라 부른다. C-Node를 이용한 라우팅으로 기존의 라우팅 프로토콜보다 경로 실정 시간과 flooding 시간을 줄이므로서 효율적인 라우팅을 수행할 수 있게된다.

• Annual Conference of KIPS
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• 2007.11a
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• pp.1069-1072
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• 2007

MANET에서의 전통적인 라우팅 프로토콜은 일반적으로 두 종류로 나눠지는데 proactive 라우팅 프로토콜과 on-demand 라우팅 프로토콜이다. 라우팅 정보의 proactive 전파와 reactive 발견 사이에는 필수적인 trade-off 가 존재한다. 모든 시나리오들을 충족하는 라우팅 프로토콜이 존재하지 않는 것은 분명하다. 그래서 최적의 라우팅 프로토콜을 발견하기 위한 연구가 계속되고 있으며 IETF의 MANET 워킹그룹은 여러 다른 프로토콜을 제안 중에 있고 그 중에 하나가 on-demand 라우팅 프로토콜의 AODV를 계승한 DYMO(Dynamic MANET On-demand)이다. DYMO는 경로 축적 메커니즘을 채택하였다. 경로 발견 과정에서 노드들은 라우팅 메시지를 포워딩하기 전에 그들 자신의 라우팅 정보도 패킷에 추가할 수 있다. 결국 소스와 목적지 사이의 모든 노드들의 라우팅 정보가 교환되는 것이다. 이 논문에서는 이 경로 축적 메커니즘의 사용 유무에 따라 다양한 속도와 트래픽 부하에서 DYMO의 성능이 어떻게 변하고 최적의 환경은 무엇인지 연구해보고자 한다.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.46 no.2
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• pp.36-43
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• 2009

In this paper, we propose a Cooperative Routing using ARQ-based Transmission (CRARQ) in Mobile Ad-hoc Wireless Sensor Networks (MAWSN). The goals of the CRARQ are to improve both the efficiency of transmission and the reliability of transmission together. The main features and contributions of the proposed CRARQ for supporting these goals are as follows. First, CRARQ uses a reactive concept to construct a route from a source to a destination. Second, CRARQ chooses the most stable relay at each hop along the route by mobility-based strategy. Third, cooperative transmission using the ARQ technique which can improve reliability is used at each hop to send data packets from source to destination. Finally, we present a theoretical analysis model for the proposed CRARQ. The performance evaluation of our protocol is implemented via simulation using Optimized Network Engineering Tool (OPNET) and analysis. The results of both simulation and analysis show that CRARQ achieves the improved packet delivery ratio (PDR) and outage probability.