Providing efficient packet delivery in vehicular ad hoc networks （VANETs） is particularly challenging due to the vehicle move- ment and lossy wireless channels. A data packet can be lost at a forwarding node even wh...Providing efficient packet delivery in vehicular ad hoc networks （VANETs） is particularly challenging due to the vehicle move- ment and lossy wireless channels. A data packet can be lost at a forwarding node even when a proper node is selected as the for- warding node. In this paper, we propose a loss-tolerant scheme for unicast routing protocols in VANETs. The proposed scheme employs multiple forwarding nodes to improve the packet reception ratio at the forwarding nodes. The scheme uses network coding to reduce the number of required transmissions, resulting in a significant improvement in end-to-end packet delivery ratio with low message overhead. The effectiveness of the proposed scheme is evaluated by using both theoretical analysis and computer sim-展开更多
As for safety applications of vehicular Ad-hoc network （VANET）, many valuable broadcast protocols have been proposed nowadays, most of which are based on either senders or receivers. In fact, sender-based protocols ...As for safety applications of vehicular Ad-hoc network （VANET）, many valuable broadcast protocols have been proposed nowadays, most of which are based on either senders or receivers. In fact, sender-based protocols would fall into invalidation due to high mobility of network, while receiver-based ones would generate extra delay. Combining both the advantages of the two schemes, this paper proposes an efficient and reliable broadcast protocol based on quality of forwarding （ERBPQF） of candidate nodes. In ERBPQF, a double-phase relay scheme is presented to reach fast message dissemination in the first phase and to ensure high packet delivery ratio （PDR） in the second phase. Then, considering signal fading, channel contention, queuing delay, broadcast interference and high mobility of vehicles, a new metric called quality of forwarding （QoF） for relay selection is further proposed. The simulation results show that the delay and dissemination efficiency （DE） of ERBPQF outperforms slotted-1 protocol, accompanying with the achievement of more than 95% PDR.展开更多
随着远程会议、远程教育和交互式仿真等分布式多媒体应用的兴起,组播技术受到网络研究人员的重视.而这些应用的QoS(quality of service)需求又进一步推动了QoS敏感的组播路由协议的发展.在已提出的各种QoS组播路由协议中,如何提高呼叫...随着远程会议、远程教育和交互式仿真等分布式多媒体应用的兴起,组播技术受到网络研究人员的重视.而这些应用的QoS(quality of service)需求又进一步推动了QoS敏感的组播路由协议的发展.在已提出的各种QoS组播路由协议中,如何提高呼叫成功率、增强规模伸缩性、降低控制报文开销,仍然是一个有待探索的问题.提出了一个新的QoS组播路由协议,其基本思想是使路由器只存储其两层邻居节点的可达性信息以及链路的QoS状态信息,以减少路由器存储开销,提高协议的规模伸缩性(scalability).协议采用受限的泛播技术,构造了一个接受节点发起的、采用多路径技术的、分布式路由算法.描述了协议的数据结构、组播树的构造算法,并给出了模拟实验结果.分析表明,基于受限泛播技术的组播路由协议具有节点存储开销小、呼叫接收成功率高等特点.虽然该协议付出了泛播引起的额外带宽开销较大的代价,但是由于协议所需要的控制数据总量不大,加上两层存储结构在一定程度上限制了泛播通信量,因此该方案具有很好的性能.展开更多
基金supported in part by JSPS KAKENHI under Grant Number25730053
文摘Providing efficient packet delivery in vehicular ad hoc networks （VANETs） is particularly challenging due to the vehicle move- ment and lossy wireless channels. A data packet can be lost at a forwarding node even when a proper node is selected as the for- warding node. In this paper, we propose a loss-tolerant scheme for unicast routing protocols in VANETs. The proposed scheme employs multiple forwarding nodes to improve the packet reception ratio at the forwarding nodes. The scheme uses network coding to reduce the number of required transmissions, resulting in a significant improvement in end-to-end packet delivery ratio with low message overhead. The effectiveness of the proposed scheme is evaluated by using both theoretical analysis and computer sim-
基金supported by the National Natural Science Foundation of China (61271184, 61571065)the National Science and Technology Major Project (2015ZX03003012)
文摘As for safety applications of vehicular Ad-hoc network （VANET）, many valuable broadcast protocols have been proposed nowadays, most of which are based on either senders or receivers. In fact, sender-based protocols would fall into invalidation due to high mobility of network, while receiver-based ones would generate extra delay. Combining both the advantages of the two schemes, this paper proposes an efficient and reliable broadcast protocol based on quality of forwarding （ERBPQF） of candidate nodes. In ERBPQF, a double-phase relay scheme is presented to reach fast message dissemination in the first phase and to ensure high packet delivery ratio （PDR） in the second phase. Then, considering signal fading, channel contention, queuing delay, broadcast interference and high mobility of vehicles, a new metric called quality of forwarding （QoF） for relay selection is further proposed. The simulation results show that the delay and dissemination efficiency （DE） of ERBPQF outperforms slotted-1 protocol, accompanying with the achievement of more than 95% PDR.
文摘随着远程会议、远程教育和交互式仿真等分布式多媒体应用的兴起,组播技术受到网络研究人员的重视.而这些应用的QoS(quality of service)需求又进一步推动了QoS敏感的组播路由协议的发展.在已提出的各种QoS组播路由协议中,如何提高呼叫成功率、增强规模伸缩性、降低控制报文开销,仍然是一个有待探索的问题.提出了一个新的QoS组播路由协议,其基本思想是使路由器只存储其两层邻居节点的可达性信息以及链路的QoS状态信息,以减少路由器存储开销,提高协议的规模伸缩性(scalability).协议采用受限的泛播技术,构造了一个接受节点发起的、采用多路径技术的、分布式路由算法.描述了协议的数据结构、组播树的构造算法,并给出了模拟实验结果.分析表明,基于受限泛播技术的组播路由协议具有节点存储开销小、呼叫接收成功率高等特点.虽然该协议付出了泛播引起的额外带宽开销较大的代价,但是由于协议所需要的控制数据总量不大,加上两层存储结构在一定程度上限制了泛播通信量,因此该方案具有很好的性能.
