• Title/Summary/Keyword: Ad hoc networks

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Handling Malicious Flooding Attacks through Enhancement of Packet Processing Technique in Mobile Ad Hoc Networks

  • Kim, Hyo-Jin;Chitti, Ramachandra Bhargav;Song, Joo-Seok
    • Journal of Information Processing Systems
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    • v.7 no.1
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    • pp.137-150
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    • 2011
  • Mobile ad hoc networks are expected to be widely used in the near future. However, they are susceptible to various security threats because of their inherent characteristics. Malicious flooding attacks are one of the fatal attacks on mobile ad hoc networks. These attacks can severely clog an entire network, as a result of clogging the victim node. If collaborative multiple attacks are conducted, it becomes more difficult to prevent. To defend against these attacks, we propose a novel defense mechanism in mobile ad hoc networks. The proposed scheme enhances the amount of legitimate packet processing at each node. The simulation results show that the proposed scheme also improves the end-to-end packet delivery ratio.

Cluster-head Decision Method for Cognitive Radio Based on Wireless Ad-hoc Network (인지 무선 기반 애드 혹 네트워크에서의 클러스터 헤드 선정기법)

  • Lee, Kyung-Sun;Kim, Yoon-Hyun;Kim, Jin-Young
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.12 no.1
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    • pp.91-96
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    • 2012
  • Ad-hoc networks can be used various environment, which it is difficult to construct infrastructures, such as shadowing areas, disaster areas, war area, and so on. In order to support to considerable and various wireless services, more spectrum resources are needed. However, efficient utilization of the frequency resource is difficult because of spectrum scarcity and the conventional frequency regulation. Ad-hoc networks employing cognitive radio (CR) system that guarantee high spectrum utilization provide effective way to increase the network capacity. In CR based wireless ad-hoc networks, cluster-head decides the existence of primary user using sensing information of primary user from each ad-hoc device. However, it is still defective research to decide cluster head among the a lot of ad-hoc devices. So, in this paper, we show the decision method of cluster head in CR based wireless and detection probabilities of primary user based on decision method of cluster head.

TCP Performance Analysis over Mobile ad-hoc Networks (모바일 ad-hoc 네트워크에서 TCP 성능 분석)

  • Nam, Ho-Seok;Cho, Sol;Lee, Tae-Hoon;Kim, Jun-Nyun
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.32 no.12B
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    • pp.800-808
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    • 2007
  • With the development of wireless data communication technology, all IP-based network will become compositions of wired and wireless networks. TCP is a connection-oriented, reliable transport protocol and has been used as de facto standard in most wired networks. Because TCP's congestion control algorithm could not distinguish congestion from BER, link failure and frequent route changes, TCP shows a poor performance over mobile ad-hoc networks. In this paper, the theoretical feature of TCP was studied and the performance of TCP over mobile ad-hoc networks was analyzed with ns2.

Energy-Efficient Routing Protocol for Hybrid Ad Hoc Networks (하이브리드 애드 혹 네트워크에서의 에너지 효율성을 고려한 라우팅 알고리즘)

  • Park, Hye-Mee;Park, Kwang-Jin;Choo, Hyun-Seung
    • Journal of Internet Computing and Services
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    • v.8 no.5
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    • pp.133-140
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    • 2007
  • Currently, as the requirement for high quality Internet access from anywhere at anytime is consistently increasing, the interconnection of pure ad hoc networks to fixed IP networks becomes increasingly important. Such integrated network, referred to as hybrid ad hoc networks, can be extended to many applications, including Sensor Networks, Home Networks, Telematics, and so on. We focus on some data communication problems of hybrid ad hoc networks, such as broadcasting and routing. In particular. power failure of mobile terminals is the most important factor since it affects the overall network lifetime. We propose an energy-efficient routing protocol based on clustering for hybrid ad hoc networks. By applying the index-based data broadcasting and selective tuning methods, the infra system performs the major operations related to clustering and routing on behalf of ad hoc nodes. The proposed scheme reduces power consumption as well as the cost of path discovery and maintenance, and the delay required to configure the route.

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Optimizing Energy Efficiency in Mobile Ad Hoc Networks: An Intelligent Multi-Objective Routing Approach

  • Sun Beibei
    • IEMEK Journal of Embedded Systems and Applications
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    • v.19 no.2
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    • pp.107-114
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    • 2024
  • Mobile ad hoc networks represent self-configuring networks of mobile devices that communicate without relying on a fixed infrastructure. However, traditional routing protocols in such networks encounter challenges in selecting efficient and reliable routes due to dynamic nature of these networks caused by unpredictable mobility of nodes. This often results in a failure to meet the low-delay and low-energy consumption requirements crucial for such networks. In order to overcome such challenges, our paper introduces a novel multi-objective and adaptive routing scheme based on the Q-learning reinforcement learning algorithm. The proposed routing scheme dynamically adjusts itself based on measured network states, such as traffic congestion and mobility. The proposed approach utilizes Q-learning to select routes in a decentralized manner, considering factors like energy consumption, load balancing, and the selection of stable links. We present a formulation of the multi-objective optimization problem and discuss adaptive adjustments of the Q-learning parameters to handle the dynamic nature of the network. To speed up the learning process, our scheme incorporates informative shaped rewards, providing additional guidance to the learning agents for better solutions. Implemented on the widely-used AODV routing protocol, our proposed approaches demonstrate better performance in terms of energy efficiency and improved message delivery delay, even in highly dynamic network environments, when compared to the traditional AODV. These findings show the potential of leveraging reinforcement learning for efficient routing in ad hoc networks, making the way for future advancements in the field of mobile ad hoc networking.

Call Admission Control in Wireless Ad-hoc Networks with Multiple Channels and Radios

  • Ko, Sung-Won
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.21 no.4
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    • pp.104-114
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    • 2007
  • In this paper, an Ad-hoc Routing Protocol that works in wireless Ad-hoc communication networks with multiple radios and multiple channels and that controls call admission based on bandwidth measurement is proposed. Unlike the conventional Ad-hoc node with a single radio using a single channel, an Ad-hoc node of the protocol proposed, the MCQosR(Multiple Channel Quality of Service Routing), has multiple radios and uses multiple channels, which allows full duplex transmission between wireless Ad-hoc nodes, and reduces intra interference on the route. Also, a fixed channel only for reception at each node enables the estimation of the available bandwidth, which is used to control the call admission for QoS provision. The performance of the MCQosR was verified by simulation.

AOZDV(Ad Hoc On-demand Zone and Distance-Vector) : A Routing Protocol with Novel Zone Mechanism in Wireless Ad hoc Networks (무선 Ad hoc 망의 새로운 Zone 기법을 적용한 AOZDV(Ad Hoc On-demand Zone and Distance-Vector) 라우팅 프로토콜)

  • Kim Yong-Woo;Choi Sung-Jae;Lee Hong-Ki;Song Joo-Seok
    • Journal of KIISE:Information Networking
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    • v.33 no.4
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    • pp.299-309
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    • 2006
  • In Mobile ad hoc networks, AODV is one of the famous on-demand routing protocol, which use the routing tables in the nodes if possible, or Route Discovery Process (RDP) is triggered to find a new route. However increasing the traffic of RDP causes dropping of the network performance in the large size of ad hoc networks. In this paper, we propose a novel routing protocol, named as AOZDV (Ad hoc On-demand Zone and Distance-Vector Routing), which enhances the AODV protocol with zone routing. AOZDV creates a Zone with neighbor nodes of the source/destination using traffic and power information, and utilizes Destination-Vector Table for internal routing in the Zone. We show by simulations that AOZDV can reduce the occurrence rate of route fail and RDP caused by route fail compared to existing routing protocols such as DSR and AODV.

Analysis of Three-Phase Multiple Access with Continual Contention Resolution (TPMA-CCR) for Wireless Multi-Hop Ad Hoc Networks

  • Choi, Yeong-Yoon;Nosratinia, Aria
    • Journal of Communications and Networks
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    • v.13 no.1
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    • pp.43-49
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    • 2011
  • In this paper, a new medium access control (MAC) protocol entitled three-phase multiple access with continual contention resolution (TPMA-CCR) is proposed for wireless multi-hop ad hoc networks. This work is motivated by the previously known three-phase multiple access (TPMA) scheme of Hou and Tsai [2] which is the suitable MAC protocol for clustering multi-hop ad hoc networks owing to its beneficial attributes such as easy collision detectible, anonymous acknowledgment (ACK), and simple signaling format for the broadcast-natured networks. The new TPMA-CCR is designed to let all contending nodes participate in contentions for a medium access more aggressively than the original TPMA and with continual resolving procedures as well. Through the systematical performance analysis of the suggested protocol, it is also shown that the maximum throughput of the new protocol is not only superior to the original TPMA, but also improves on the conventional slotted carrier sense multiple access (CSMA) under certain circumstances. Thus, in terms of performance, TPMA-CCR can provide an attractive alternative to other contention-based MAC protocols for multi-hop ad hoc networks.

Analysis the Overhead of IEEE 802.11 RTS/CTS Handshake in Ad-hoc Networks Based Multipath Routing (다중경로 라우팅 기반 Ad-hoc Networks에서 IEEE 802.11 RTS/CTS 핸드세이크 오버헤드 분석)

  • Kim, Hyun-Chang;Lee, Jai-Yong
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.45 no.6
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    • pp.33-44
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    • 2008
  • Multipath routing protocols with load balance, fault tolerance, aggregated bandwidth in Ad-hoc Networks provide improved throughput and reliable route as compared with singlepath routing protocols. However, multipath routing protocols have not been explored thoroughly in the domain of overhead in Ad-hoc Networks. In this paper, we analyze and compare on-demand singlepath and multipath routing with IEEE 802.11 DCF in terms of Routing overhead and MAC overhead. The results reveals that in comparison with singlepath routing protocol, multipath routing mechanism creates more overheads but provides better performance in congestion and capacity provided that the route length is within a certain upper bound which is derivable. The analytical results are further confirmed by simulation.

An Enhanced Routing Protocol for Support Mobility in Mobile Ad hoc Networks (이동 ad hoc 네트워크의 이동성을 지원하기 위한 향상된 라우팅 프로토콜)

  • Kim, Kwan-Woong;Kim, Dae-Ik
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.45 no.6
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    • pp.131-138
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    • 2008
  • 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 paper, an enhanced routing protocol based on AODV(Ad hoc On-demand Distance Vector routing) by monitoring variation of receiving signal strength is proposed. New metric function that consists of node mobility and hops of path is used for routing decision. For preventing route failure by node movement during data transmission, a new route maintenance named as LRC (Local Route Change) is presented. If the node movement is detected, the routing agent switches path to its neighbor node in LRC. Simulation results show that the performance of the proposed routing scheme is superior to previous AODY protocol.