速度自适应广播算法在车载自组织网络中的应用研究

Speed Adaptive Probabilistic Broadcast for Scalable Data Dissemination in Vehicular Ad hoc Networks

车载Ad hoc网络(VANETs)是自组织网络,可以支持不同类型的交通信息系统且不需要固定的基础设施或集中管理。由于交通数据是用户的公共利益和而不是具体的某个人,它更适合依靠在VANETs发布数据广播方案。然而,密集网络中的广播产生了大量的冗余数据,这些数据浪费了有限的无线信道带宽;此外,因为在同一地点附近的车辆可能转播相同的数据,数据包冲突可能会导致广播风暴。处理这种可伸缩性问题的常用解决方案是减少冗余数据的百分比。这通常是通过只选择部分车辆中继数据包而不是让每一个车辆进行转播。本文提出了根据行驶车辆的速度来确定转播的概率速度,从而提高数据分发的可扩展性作为VANETs的高流动性特点。

Vehicular ad hoc networks（VANETs）are self-organizing networks that can support different types of traffic information systems without requiring fixed infrastructure or centralized administration.Since traffic data is of public interest and usually benefits a group of users rather than a specific individual,it is more appropriate to rely on a broadcasting scheme for data dissemination in VANETs.However,broadcasting in dense networks suffers from a high percentage of redundant data that wastes the limited radio channel bandwidth.Moreover,packet collisions may lead to the broadcast storm problem since a large number of vehicles in the same vicinity may rebroadcast the same data nearly simultaneously.A common employed solution to deal with such scalability issues is reducing the percentage of redundant data.This is typically done by selecting only some of the vehicles to relay data packet as opposed to letting every single vehicle rebroadcast it.In this work,we propose involving the high mobility feature of VANETs to improve scalability in data dissemination,by relying on the speed of travelling vehicles to determine the rebroadcasting probability.