This paper studies a routing protocol used in the application of collecting real-time traffic information using mobile vehicles to monitor traffic status. The biggest challenge of vehicular ad hoe network routing prot...This paper studies a routing protocol used in the application of collecting real-time traffic information using mobile vehicles to monitor traffic status. The biggest challenge of vehicular ad hoe network routing protocol lies in the mismatch between the direction of moving vehicles and routed data. In order to deal with this mismatch, a mesh based routing protocol with a two-tier network architecture is proposed. By using mesh nodes deployed at intersections, data can be routed through an optimized path which can improve the delivery ratio and reduce the consumption of network resources. The simulation uses the mobility model processed from the GPS data of taxis mnning in Shanghai urban areas. The result shows that the proposed protocol outperforms the existing flooding protocol.展开更多
Mobile ad hoc networks are particularly vulnerable to denial of service （DOS） attacks launched through compromised nodes or intruders. In this paper, we present a new DOS attack and its defense in ad hoc networks. T...Mobile ad hoc networks are particularly vulnerable to denial of service （DOS） attacks launched through compromised nodes or intruders. In this paper, we present a new DOS attack and its defense in ad hoc networks. The new DOS attack, called AA hoc Flooding Attack（AHFA）, is that intruder broadcasts mass Route Request packets to exhaust the communication bandwidth and node resource so that the valid communication can not be kept. After analyzed AM hoc Flooding Attack, we develop Flooding Attack Prevention （FAP）, a genetic defense against the AM hoc Flooding Attack. When the intruder broadcasts exceeding packets of Route Request, the immediate neighbors of the intruder record the rate of Route Request. Once the threshold is exceeded, nodes deny any future request packets from the intruder. The results of our implementation show FAP can prevent the AM hoe Flooding attack efficiently.展开更多
Route flapping is common in mobile Ad hoc networks.It usually causes large delay or even interruption during communication.This paper proposed a routing protocol AODV-RM to alleviate this effect.AODV-RM selects routes...Route flapping is common in mobile Ad hoc networks.It usually causes large delay or even interruption during communication.This paper proposed a routing protocol AODV-RM to alleviate this effect.AODV-RM selects routes with the lightest traffic load,to avoid striving for hot nodes with other users,hence minishes the chance of collision.AODV-RM keeps all valid routes to the destination in its routing table as backups.When the link under usage breaks down,AODV-RM shifts to a valid route in its routing table instead of route repair or researching,which ensures the continuity of communication.AODV-RM chooses a route maintenance scheme by the network topology.If the origination has multi routes to the destination,only the origination maintains routes.Otherwise,middle nodes,instead of the origination,maintain sub-routes to the destination.By simulating the traditional AODV and AODV-RM,the results showed that AODV-RM has a lower drop rate and better performance against route flapping.展开更多
Ad Hoc网络是由一组移动节点在没有任何现存网络基础设施或是集中管理的情况下形成的动态网络。论文利用NS2网络仿真软件,在不同的网络负载、移动性和网络规模等条件下,分析比较AdHoc网络的四种路由协议DSR、AODV、DSDV和洪泛协议的性...Ad Hoc网络是由一组移动节点在没有任何现存网络基础设施或是集中管理的情况下形成的动态网络。论文利用NS2网络仿真软件,在不同的网络负载、移动性和网络规模等条件下,分析比较AdHoc网络的四种路由协议DSR、AODV、DSDV和洪泛协议的性能。仿真结果表明由于各协议适用范围不同,因此可根据具体情况自适应地进行协议选择。展开更多
基于节点能量的约束,以能量消耗程度、节点终止情况和连通性为指标,对A d Hoc网络4种典型的路由协议在不同的运动场景下进行了比较系统的仿真研究,得出了与相关文献不尽一致的结论.基于仿真结果,认为基于能耗研究A d Hoc网络路由协议应...基于节点能量的约束,以能量消耗程度、节点终止情况和连通性为指标,对A d Hoc网络4种典型的路由协议在不同的运动场景下进行了比较系统的仿真研究,得出了与相关文献不尽一致的结论.基于仿真结果,认为基于能耗研究A d Hoc网络路由协议应以节点能耗的平衡性来考虑问题,而不仅仅只以能耗量的多少来衡量协议性能的优劣.展开更多
基金Supported by the National Basic Research Program of China (No. 2006CB303000)the National Natural Science Foundation of China (No. 60773091, F020303).
文摘This paper studies a routing protocol used in the application of collecting real-time traffic information using mobile vehicles to monitor traffic status. The biggest challenge of vehicular ad hoe network routing protocol lies in the mismatch between the direction of moving vehicles and routed data. In order to deal with this mismatch, a mesh based routing protocol with a two-tier network architecture is proposed. By using mesh nodes deployed at intersections, data can be routed through an optimized path which can improve the delivery ratio and reduce the consumption of network resources. The simulation uses the mobility model processed from the GPS data of taxis mnning in Shanghai urban areas. The result shows that the proposed protocol outperforms the existing flooding protocol.
基金This project was supported by the National"863"High Technology Development Programof China (2003AA148010) Key Technologies R&D Programof China (2002DA103A03 -07)
文摘Mobile ad hoc networks are particularly vulnerable to denial of service （DOS） attacks launched through compromised nodes or intruders. In this paper, we present a new DOS attack and its defense in ad hoc networks. The new DOS attack, called AA hoc Flooding Attack（AHFA）, is that intruder broadcasts mass Route Request packets to exhaust the communication bandwidth and node resource so that the valid communication can not be kept. After analyzed AM hoc Flooding Attack, we develop Flooding Attack Prevention （FAP）, a genetic defense against the AM hoc Flooding Attack. When the intruder broadcasts exceeding packets of Route Request, the immediate neighbors of the intruder record the rate of Route Request. Once the threshold is exceeded, nodes deny any future request packets from the intruder. The results of our implementation show FAP can prevent the AM hoe Flooding attack efficiently.
基金Sponsored by the National Natural Science Foundation of China(Grant No. 60432040)the Program for New Century Excellent Talents in University(Grant No.NCET-04-0332)
文摘Route flapping is common in mobile Ad hoc networks.It usually causes large delay or even interruption during communication.This paper proposed a routing protocol AODV-RM to alleviate this effect.AODV-RM selects routes with the lightest traffic load,to avoid striving for hot nodes with other users,hence minishes the chance of collision.AODV-RM keeps all valid routes to the destination in its routing table as backups.When the link under usage breaks down,AODV-RM shifts to a valid route in its routing table instead of route repair or researching,which ensures the continuity of communication.AODV-RM chooses a route maintenance scheme by the network topology.If the origination has multi routes to the destination,only the origination maintains routes.Otherwise,middle nodes,instead of the origination,maintain sub-routes to the destination.By simulating the traditional AODV and AODV-RM,the results showed that AODV-RM has a lower drop rate and better performance against route flapping.
文摘基于节点能量的约束,以能量消耗程度、节点终止情况和连通性为指标,对A d Hoc网络4种典型的路由协议在不同的运动场景下进行了比较系统的仿真研究,得出了与相关文献不尽一致的结论.基于仿真结果,认为基于能耗研究A d Hoc网络路由协议应以节点能耗的平衡性来考虑问题,而不仅仅只以能耗量的多少来衡量协议性能的优劣.
