| 摘要: |
| 节点高速移动造成网络拓扑频繁变化,使得车载自组网的数据分发充满挑战.研究表明,基于洪泛原理的一类数据分发机制能够可靠有效传输车载自组网中的数据,但没有较好地实现传输成功率、传输时延和消息冗余副本之间的折中.提出一种节点密度自适应的数据分发策略,通过分布式节点密度感知算法,使每个节点快速获知整个网络中热点区域的分布.基于节点与热点间的欧氏距离和节点密度建立跳数限制函数,动态对转发消息进行跳数限制,减少在热点区域的副本复制,有效地降低网络中消息冗余副本数量.仿真实验结果表明,本文方法在传输成功率和时延方面与epidemic协议接近,但冗余消息副本数减少了37.5%,有效地折衷了三者之间的关系. |
| 关键词: 车载自组网 数据分发 热点 节点密度 |
| DOI： |
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| 基金项目:国家自然科学基金(61073014);国家重大专项(2010ZX03006-007);河南省科技攻关项目(102102210121,102102210026);中国科学院知识创新工程领域前沿项目(ISCAS2009-DR04);河南工业大学博士基金项目(2009BS021);河南工业大学校科研重点项目(09XZD004) |
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| Data Dissemination Scheme Based on Adaptive Density of Nodes in Vehicular Ad-Hoc Networks |
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YANG Wei-Dong1, LIU Ji-Zhao1, LIU Yan2, DENG Miao-Lei1, ZHOU Xin-Yun3
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1.College of Information Science and Engineering, He’nan University of Technology, Zhengzhou 450001, China;2.School of Software and Microelectronics, Peking University, Beijing 102600, China;3.State Key Laboratory of Information Security, Institute of Software, The Chinese Academy of Sciences, Beijing 100190, China
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| Abstract: |
| The high mobility of vehicles causes the frequent change of networks topology.This is part of a huge huge challenge on the data dissemination of VANETs.Even though existing flood-based routing protocols provide high reliability,they can not achieve the good trade-off shown among delivery ratio,delay,and the number of message redundant copies.A data dissemination scheme based on adaptive node density for VANETs is proposed. Nodes can rapidly gain the geographical distribution of“hotspot”regions via the proposed distributed algorithm. The hop-count limit function is established which is based on the Euclidean distance of the nearest“hostspot” region and density of nodes.When making forwarding deciding,nodes set a dynamically upper bound on the message hop count to avoiding unnecessary message redundant copies in the“hotspot”region.The number of message redundant copies can be effectively reduced in the network.The simulation results show that the delivery ratio and delay of this scheme are close to the epidemic routing protocol,but the number of message copies can be reduced by 37.5%. |
| Key words: vehicular ad-hoc network data dissemination hotspot node density |
