• Title/Summary/Keyword: Ad hoc routing protocols

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Routing Protocol Based on Zone Master for Hybrid Wireless Networks (하이브리드 무선 네트워크를 위한 존 마스터 기반의 라우팅 프로토콜)

  • Lim, Se-Young;Kim, Hun;Yoo, Myung-Sik
    • Journal of KIISE:Information Networking
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    • v.34 no.4
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    • pp.269-275
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    • 2007
  • Since being constructed without any infrastructure-based network, ad hoc network has been received much attention as a key technology for ubiquitous networks. Due to high bit error rate and dynamically changing network topology in ad hoc network, the routing protocol that provides stable multi-hop communication path is the one of the key issues to address. The previously proposed ad hoc routing protocols have their limitations on network overhead, stability, and scalability. In this paper, we consider hybrid wireless network, which can overcome shortcomings of ad hoc network, and propose a novel routing protocol called zone master-based routing protocol. We verify with computer simulations that the proposed routing protocol outperforms other existing routing protocols in the various wireless environments.

An Efficient Routing Algorithm for Solving the Lost Link Problem of Vehicular Ad-hoc Networks (차량 애드혹 네트워크의 링크 단절 문제 해결을 위한 효율적인 라우팅 알고리즘)

  • Lim, Wan-Seon;Kim, Sok-Hyong;Suh, Young-Joo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.12B
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    • pp.1075-1082
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    • 2008
  • A greedy forwarding algorithm is one of the most suitable solutions for routing in vehicular ad-hoc networks. Compared to conventional routing protocols for mobile ad-hoc networks, greedy forwarding based routing protocols maintain only local information of neighbors instead of per-destination routing entries, and thus they show better performance in highly-mobile vehicular ad-hoc networks. With greedy forwarding, each node learns its geographical position and periodically broadcasts a beacon message including its position information. Based on the position information, each node selects a neighbor node located closest to the destination node as the next forwarder. One of the most serious problems in greedy forwarding is the lost link problem due to the mobility of nodes. In this paper, we propose a new algorithm to reduce the lost link problem. The proposed algorithm aims to find an efficient and stable routing path by taking account of the position of neighbors and the last beacon reception time. Our simulation results show that the proposed algorithm outperforms the legacy greedy algorithm and its variants.

Traffic Load-aware Reactive Routing Scheme in Wireless Mobile Ad hoc Network (무선 이동 애드 혹 네트워크에서 트래픽 부하를 고려한 리액티브 라우팅 기술)

  • Ko, Sung-Won
    • 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.

TCP Performance Improvement Considering ACK Loss in Ad Hoc Networks

  • Kim, Dong-Kyun;Yoo, Hong-Seok
    • Journal of Communications and Networks
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    • v.10 no.1
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    • pp.98-107
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    • 2008
  • In mobile ad hoc networks, packet loss is unavoidable due to MAC contention, link failure or the inherent characteristics of wireless link. Since TCP relies on the timely reception of TCP ACK packets to progress the transmission of the TCP DATA packets, ACK loss obviously affects the performance due to two main problems: (a) Frequent occurrence of spurious retransmissions caused by timeout events and (b) impairment of the fast retransmit mechanism caused by the lack of a sufficient number of duplicate ACK packets. In particular, since most reactive routing protocols force the packets buffered over a path to be discarded while performing a route recovery, the performance degradation becomes more serious due to such ACK loss. In this paper, therefore, TCP with two piggybacking schemes (called TCP-pgy) is proposed in order to resolve the above-mentioned problems over reactive routing protocols. Through extensive simulations using the ns-2 simulator, we prove that our proposed schemes contribute to TCP performance improvements.

Route Selection Protocol based on Energy Drain Rates in Mobile Ad Hoc Networks (무선 Ad Hoc 통신망에서 에너지 소모율(Energy Drain Rate)에 기반한 경로선택 프로토콜)

  • Kim, Dong-Kyun
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.28 no.7A
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    • pp.451-466
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    • 2003
  • Untethered nodes in mobile ad-hoc networks strongly depend on the efficient use of their batteries. In this paper, we propose a new metric, the drain rate, to forecast the lifetime of nodes according to current traffic conditions. This metric is combined with the value of the remaining battery capacity to determine which nodes can be part of an active route. We describe new route selection mechanisms for MANET routing protocols, which we call the Minimum Drain Rate (MDR) and the Conditional Minimum Drain Rate (CMDR). MDR extends nodal battery life and the duration of paths, while CMDR also minimizes the total transmission power consumed per packet. Using the ns-2 simulator and the dynamic source routing (DSR) protocol, we compare MDR and CMDR against prior proposals for power-aware routing and show that using the drain rate for power-aware route selection offers superior performance results.

A Reliable Route Selection Algorithm in Mobile Ad-hoc Networks (이동 애드혹 네트워크에서의 안정 경로 선택 알고리즘)

  • Kim, Won-Ik;Suh, Young-Joo;An, Syung-Og
    • Journal of KIISE:Information Networking
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    • v.29 no.3
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    • pp.314-323
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    • 2002
  • The routing protocols designed for wired networks can hardly be used for mobile ad-hoc networks due to limited bandwidth of wireless transmission and unpredictable topological change. Recently, several routing protocols for mobile ad-hoc networks have been Proposed. However, when theme protocols are applied to support real time services like multimedia transmission, they still have problems in ad-hoc networks, where the topology changes drastically. In this paper, we propose a new route selection algorithm which selects the most reliable route that is impervious to route failures by topological changes by mobile hoots. For reliable route selection, the concept of virtual zone (stable zone and caution zone) is proposed. The zone is located in a mobile node'transmission range and determined by mobile node's mobility information received by Global Positioning System (GPS). The proposed algorithm is applied to the route discovery procedure of the existing on-demand routing protocol, AODV, and evaluated by simulation in various traffic conditions and mobility patterns.

QoS Routing Protocol using multi path in Unidirectional Mobile Ad Hoc Networks (단방향 이동 Ad Hoc 망에서의 다중경로를 이용한 QoS 라우팅 프로토콜)

  • Kang, Kyeong-In;Park, Kyong-Bae;Yoo, Choong-Yul;Jung, Chan-Hyeok;Lee, Kwang-Bae;Kim, Hyun-Ug
    • The KIPS Transactions:PartC
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    • v.9C no.6
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    • pp.935-944
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    • 2002
  • It is the Mobile Ad Hoc Networks that constituted with serveral mobile node that can communicate with other mobile nodes. Until now, there were no routing protocols considering such as Multimediadata, VOD (Video On Demand), which is required of lots of bandwidth in Mobile Ad Hoc Network, io we are in the need of QoS (Quality of Service)routing protocol to transmit the data packets faster and more accurate. Also, there are an unidirectional links due to asymmetric property of mobile terminals or current wireless environments on practical mobile ad hoc networks. However, at present, the existing mobile ad hoc routing protocols are implemented to support only bidirectional links. In this paper, we propose the Advanced Routing routing protocol in order to implement a new routing protocol, which is fit to mobile ad hoc networks containing unidirectional links and to support QoS service. For the performance evaluation, we use NS-2 simulator of U.C. Berkeley. We could get not only increased received data rate and decreased average route discovery time, but also network load decreases with compared Best effort service.

An Optimal ODAM-Based Broadcast Algorithm for Vehicular Ad-Hoc Networks

  • Sun, Weifeng;Xia, Feng;Ma, Jianhua;Fu, Tong;Sun, Yu
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.6 no.12
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    • pp.3257-3274
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    • 2012
  • Broadcast routing has become an important research field for vehicular ad-hoc networks (VANETs) recently. However, the packet delivery rate is generally low in existing VANET broadcast routing protocols. Therefore, the design of an appropriate broadcast protocol based on the features of VANET has become a crucial part of the development of VANET. This paper analyzes the disadvantage of existing broadcast routing protocols in VANETs, and proposes an improved algorithm (namely ODAM-C) based on the ODAM (Optimized Dissemination of Alarm Messages) protocol. The ODAM-C algorithm improves the packet delivery rate by two mechanisms based on the forwarding features of ODAM. The first distance-based mechanism reduces the possibility of packet loss by considering the angles between source nodes, forwarding nodes and receiving nodes. The second mechanism increases the redundancy of forwarding nodes to guarantee the packet success delivery ratio. We show by analysis and simulations that the proposed algorithm can improve packet delivery rate for vehicular networks compared against two widely-used existing protocols.

A Performance Comparison of On-Demand Routing Protocols for Application Services in MANET (MANET에서 응용 서비스 데이터 유형에 따른 요구기반 라우팅 프로토콜의 성능비교)

  • Jang Jun-Young;Lee Kil-Sup;Lee Sung Jong
    • The KIPS Transactions:PartC
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    • v.11C no.7 s.96
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    • pp.871-878
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    • 2004
  • Recenty, there has been great interest in MANET from various areas. In this paper we focus on performance analysis of on demand routing protocols surf as DSR, AODV, and TORA in MANET. We have conducted several simulations concerned with application service data such as sensor, text. voice, and video data. And then, we have evaluated the performance of three protocols in a pre-designed ad hoc network, which is consisted of 20 nodes. As a result, we have obtained quantitative data for packet delivery fraction, average end to-end delay, routing load, channel utilization from upper layer and supportable routing protocol for application service data. The results can be used for designing specific-purposed ad-hoc networks.

EZR: Expansive Search Zone Routing Protocol for Ship Ad Hoc Networks (선박 애드 혹 네트워크를 위한 확장탐색구역 경로배정 프로토콜)

  • Son, Joo-Young
    • Journal of Advanced Marine Engineering and Technology
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    • v.32 no.8
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    • pp.1269-1277
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    • 2008
  • Ships at sea cannot exchange data among them easily so far. Basically voice-oriented communication systems are the main methods, some of them utilize the HF radio systems at lower bit rates, and for higher bit rates, the Inmarsat or VSAT are adopted. None of them are used widely because of lower qualities and higher costs. There exist many technical and economical limits to have the Internet service just like on land such as the WWW service. In order to achieve the improved transmission rates of the maritime communication networks at farther sea, MANET(Mobile Ad Hoc Network) is one of the most practical models. In this paper, a new routing protocol named EZR (Expansive Search Zone Routing Protocol) is proposed, which is based on SANET (Ship Ad Hoc Network) model that has some different features from MANET and VANET (Vehicular Ad Hoc Network). The search zone for the shortest path is firstly found by EZR. If no path is searched in the zone, the zone is expanded according to the rule of EZR. The zone-expanding and path-searching procedures are repeated until the path is found out. The performance of EZR is evaluated and compared with LAR protocol which is one of the most typical routing protocols based on geographical information. The simulated results show that EZR is much better than LAR at sea environments in terms of routing success rate, route optimality, and a single index of performance combined the previous two metrics.