车载网中一种新的紧急消息转发方案

A New Emergency Message Forwarding Scheme in VANETs

车载网络(Vehicle Ad hoc Networks,VANETs)平台可传输时延-苛刻消息,然而,这些消息必须在限定时间内传递。因此,及时地传输消息是非常重要的。但是通过广播分发数据产生了大量的消息复本,容易形成广播风暴。为此,提出基于簇结构的紧急消息传输(Clustering-based Emergency Message Transmission,CEMT)策略。先依据车辆属性构建簇,再通过簇传输消息。同时,为了避免不必要的广播,设置定时器。只有离发送节点最远的接收节点才能重播消息,进而提高消息覆盖率,并减少了传输时延。相比于传统的消息传输策略,CEMT策略减少了传输时延,并提高消息传递率。

Vehicle Ad hoc Networks( VANETs) can be utilized to disseminate time-critical information.These critical information must be delivered within a specific period of time. Therefore,timely message dissemination is extremely important. The existing data dissemination techniques in VANETs generate a large number of messages through techniques such as broadcast or partial broadcast. Thus,the techniques based on broadcast schemes can cause congestion as all the recipients re-broadcast the message and vehicles receive multiple copies of same messages. Clustering-based Emergency Message Transmission( CEMT) mechanism is proposed in this paper. Firstly,the cluster is built according to the vehicle properties,and then the message is transmitted through the cluster. Also,to avoid unnecessary broadcasts,set a timer. Only the receiving node farthest from the sending node can replay the message,thus improving the message coverage and reducing transmission delay. Compared with traditional messaging strategy,CEMT strategy reduces transmission delay and improves messaging rate.