• Title/Summary/Keyword: Vehicular Ad hoc NETwork

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A Study on Performance of Content Store Replacement Algorithms over Vehicular CCN (VCCN에서 Content Store 교체 알고리즘의 성능에 관한 연구)

  • Choi, Jong-In;Kang, Seung-Seok
    • The Journal of the Convergence on Culture Technology
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    • v.6 no.1
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    • pp.495-500
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    • 2020
  • VANET (Vehicular Ad Hoc Network), an example of an ad hoc vehicular networks, becomes one of the popular research areas together with the self-driving cars and the connected cars. In terms of the VANET implementation, the traditional TCP/IP protocol stack could be applied to VANET. Recently, CCN (Content Centric Networking) shows better possibility to apply to VANET, called VCCN (VANET over CCN). CCN maintains several data tables including CS (Content Store) which keeps track of the currently requested content segments. When the CS becomes full and new content should be stored in CS, a replacement algorithm is needed. This paper compares and contrasts four replacement algorithms. In addition, it analyzes the transmission characteristics in diverse network conditions. According to the simulation results, LRU replacement algorithm shows better performances than the remaining three algorithms. In addition, even the size of CS is small, the network maintains a reasonable transmission performance. As the CS size becomes larger, the transmission rate increases proportionally. The transmission performance decreases when the network is crowded as well as the number of transmission hops becomes large.

Application Scenarios of Nautical Ad-hoc Network in Wireless Mobile Communication under Maritime Environment (해상 환경에서의 무선 이동 통신을 위한 선박용 Ad-hoc 네트워크 운용 시나리오)

  • Kim, Young-Bum;Chang, Kyung-Hi;Yun, Chang-Ho;Park, Jong-Won;Lim, Yong-Kon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.10
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    • pp.2097-2104
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    • 2009
  • In terrestrial communications, high data rate transmission can be achieved by splitting the coverage area into small cells through base stations and reusing the resource efficiently. However, the geographical features of maritime communications require the long transmission range, and it is not practical to install base station on the sea to set up the similar deployment as the terrestrial communications, so MF/HF band modem with low data rate are currently utilized for maritime communications. And the expensive satellite communication via Inmarsat is the conventional solution for the high data rate transmission on the sea. To reduce the cost, Ad-hoc network is proposed to apply on the sea, which requires no base station for the peer-to-peer communications. In this paper, we denominate this maritime environment specific Ad-hoc network as Nautical Ad-hoc Network (NANET). Furthermore, the deployment scenario for the NANET, and the analysis on multiple access and duplexing schemes for the NANET are discussed in this paper, which serves as the cornerstone for the further NANET research and development.

Mobility-Based Clustering Algorithm for Multimedia Broadcasting over IEEE 802.11p-LTE-enabled VANET

  • Syfullah, Mohammad;Lim, Joanne Mun-Yee;Siaw, Fei Lu
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.3
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    • pp.1213-1237
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    • 2019
  • Vehicular Ad-hoc Network (VANET) facilities envision future Intelligent Transporting Systems (ITSs) by providing inter-vehicle communication for metrics such as road surveillance, traffic information, and road condition. In recent years, vehicle manufacturers, researchers and academicians have devoted significant attention to vehicular communication technology because of its highly dynamic connectivity and self-organized, decentralized networking characteristics. However, due to VANET's high mobility, dynamic network topology and low communication coverage, dissemination of large data packets (e.g. multimedia content) is challenging. Clustering enhances network performance by maintaining communication link stability, sharing network resources and efficiently using bandwidth among nodes. This paper proposes a mobility-based, multi-hop clustering algorithm, (MBCA) for multimedia content broadcasting over an IEEE 802.11p-LTE-enabled hybrid VANET architecture. The OMNeT++ network simulator and a SUMO traffic generator are used to simulate a network scenario. The simulation results indicate that the proposed clustering algorithm over a hybrid VANET architecture improves the overall network stability and performance, resulting in an overall 20% increased cluster head duration, 20% increased cluster member duration, lower cluster overhead, 15% improved data packet delivery ratio and lower network delay from the referenced schemes [46], [47] and [50] during multimedia content dissemination over VANET.

Proposed Message Transit Buffer Management Model for Nodes in Vehicular Delay-Tolerant Network

  • Gballou Yao, Theophile;Kimou Kouadio, Prosper;Tiecoura, Yves;Toure Kidjegbo, Augustin
    • International Journal of Computer Science & Network Security
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    • v.23 no.1
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    • pp.153-163
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    • 2023
  • This study is situated in the context of intelligent transport systems, where in-vehicle devices assist drivers to avoid accidents and therefore improve road safety. The vehicles present in a given area form an ad' hoc network of vehicles called vehicular ad' hoc network. In this type of network, the nodes are mobile vehicles and the messages exchanged are messages to warn about obstacles that may hinder the correct driving. Node mobilities make it impossible for inter-node communication to be end-to-end. Recognizing this characteristic has led to delay-tolerant vehicular networks. Embedded devices have small buffers (memory) to hold messages that a node needs to transmit when no other node is within its visibility range for transmission. The performance of a vehicular delay-tolerant network is closely tied to the successful management of the nodes' transit buffer. In this paper, we propose a message transit buffer management model for nodes in vehicular delay tolerant networks. This model consists in setting up, on the one hand, a policy of dropping messages from the buffer when the buffer is full and must receive a new message. This drop policy is based on the concept of intermediate node to destination, queues and priority class of service. It is also based on the properties of the message (size, weight, number of hops, number of replications, remaining time-to-live, etc.). On the other hand, the model defines the policy for selecting the message to be transmitted. The proposed model was evaluated with the ONE opportunistic network simulator based on a 4000m x 4000m area of downtown Bouaké in Côte d'Ivoire. The map data were imported using the Open Street Map tool. The results obtained show that our model improves the delivery ratio of security alert messages, reduces their delivery delay and network overload compared to the existing model. This improvement in communication within a network of vehicles can contribute to the improvement of road safety.

Authentication Protocol for Inter-Vehicle Communication in Vehicular Ad Hoc Networks (VANET 상에서의 차량간 통신을 위한 인증 프로토콜)

  • Park, Young-Ho;Na, Jin-Han;Moon, Sang-Jae
    • Journal of Korea Society of Industrial Information Systems
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    • v.14 no.2
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    • pp.81-85
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    • 2009
  • In VANET, it is required one-way broadcast transmission because vehicles move at high speed and warning messages need to broadcast. our protocol employs digital signatures to authenticate nodes along the path. this prevents impersonation attacks and message modification attacks. our protocol also employs the node list to recognize intermediate nodes of the path. The node list, the time, and the nonce can prevent replay attacks.

A Frame Collision Reduction Method for Safety Message Broadcasting in IEEE1609.4/IEEE802.11p based VANETs

  • Wang, Lei;Jing, Weiping
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.3
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    • pp.1031-1046
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    • 2018
  • Vehicular ad hoc network (VANET) is a dedicated network to connect vehicles without any centralized administration or infrastructure. The wireless access in vehicular environments (WAVE) protocol leveraging IEEE 1609/802.11p is widely implemented for VANETs. However, in congested traffic situation, the performance of the WAVE system degrades significantly due to serious collision, especially for safety related broadcast services on the control channel (CCH) interval due to the inherent drawback of its collision avoidance mechanisms called carrier sense multiple access with collision avoidance (CSMA/CA). In this paper, we propose a method that can decrease the number of frame collisions in CCH with a few modifications to the IEEE 802.11p protocol. In the paper, vehicles still employ CSMA/CA to compete for the channel access opportunity. However, by taking advantage of periodicity of synchronization interval, a two-state switching scheme introducing two new inter frame space (IFS) is proposed to reduce the number of competing vehicles substantially and as a result, the collision probability is significantly decreased. The simulation results demonstrate the superiority of the proposed method in packet collision rate.

A Study on Vehicular Positioning Technologies for Smart/Green Cars (스마트/그린형 자동차의 위치정보시스템에 관한 연구)

  • Ro, Kap-Seong;Oh, Jun-Seok;Dong, Liang
    • Journal of The Institute of Information and Telecommunication Facilities Engineering
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    • v.9 no.3
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    • pp.92-101
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    • 2010
  • Energy efficiency and safe mobility are the two key constituents of the future automobile. The technologies that enable these features are now heavily dependent upon information and communication technology rather than traditional auto-mechanical technology. This paper presents an exploratory project 'Smart&Green Vehicle Project' at Western Michigan University which is to improve the geographical location accuracy of vehicles and to study various applications of making such location data available. Global Positioning System (GPS), Inertial Navigation System (INS), Vehicular Ad-hoc Network (VANET) technology, and data fusion among these technologies are investigated. Testing and evaluation is done on systems which will gather vehicular positioning data during GPS signal loss. Vehicles in urban settings do not acquire accurate positioning data from GPS alone; therefore there is a need for exploration into technology that can assist GPS in urban settings. The goal of this project is to improve the accuracy of positioning data during a loss of GPS signal. Controlled experiments are performed to gather data which aided in assessing the feasibility of these technologies for use in vehicular platforms.

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Routing Algorithm of VANET for an Efficient Path Management in Urban Intersections (도심 교차로에서 효율적 경로 관리를 위한 자동차 통신용 라우팅 알고리즘)

  • Cho, Sunghyun;Kim, Seokwoo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38A no.12
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    • pp.1054-1060
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    • 2013
  • This paper proposes a vehicle ad-hoc network (VANET) routing algorithm to reduce the probability of routing path discontinuity in urban intersections. In urban intersections, the vehicles may frequently change their moving directions. It can cause the disconnection of routing path and the increase of a packet transmission delay. In order to resolve this problem, the proposed routing algorithm exploits the information of moving directions in urban intersections. In this way, the proposed algorithm can reduce the probability of the local maximum which causes the increase of the number of routing hops and packet transmission delay. Simulation results show that the proposed algorithm can reduce the local maximum probability by 10% and increase the successful packet transmission ratio by 5% compared to the conventional VANET routing algorithms.

Opportunistic Broadcast Protocol for Frequent Topology Changes in Vehicular Ad-hoc Networks (차량 애드혹 네트워크의 빈번한 토폴로지 변경에 적합한 기회적 브로드캐스트 프로토콜)

  • Cha, Si-Ho;Ryu, Minwoo
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.18 no.2
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    • pp.1-8
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    • 2022
  • The message propagation between vehicles must be efficiently performed to quickly transmit information between vehicles in vehicle ad hoc networks (VANETs). Broadcasting can be the most effective solution for propagating these messages. However, broadcasting can cause broadcast storm problems, which can reduce the performance of the overall network. Therefore, rapid information delivery in VANET requires a method that can propagate messages quickly without causing the broadcast storm problems. This paper proposes a lightweight and opportunistic broadcast (LOB) protocol that leverages the features of opportunistic routing to propagate messages quickly while minimizing the load on the network in VANETs where the network topology changes frequently. LOB does not require any routing information like greedy forwarding scheme, and neighboring nodes at the farthest distance within the range of transmission nodes are likely to be selected as forwarding nodes, and multiple forwarding candidate nodes like opportunistic routing scheme can increase packet transmission rates. Simulation results using ns-2 showed that LOB outperformed existing broadcast protocols in terms of packet rate and packet delay.

Survey of Cognitive Radio VANET

  • He, Xinxin;Shi, Weisen;Luo, Tao
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.8 no.11
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    • pp.3837-3859
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    • 2014
  • Vehicular Ad hoc Networks (VANET) becomes more popular in industry, academia and government. However, Typical VANET is challenged by high speed mobility and insufficient spectrum resources over congested scenarios. To address those serious problems, some articles have introduced Cognitive Radio (CR) technology into VANET and formed CR-VANET. In this article, we propose an overview of CR-VANET by exploring different architectures and features. Moreover, we provide taxonomy of state-of-the-art papers in this emerging field and the key articles are well analyzed respectively. In addition, we illustrate both research and application frameworks of CR-VANET based on our works, and propose some open research issues for inspiring future work.