基于NDN的车联网数据转发策略研究

发布时间：2018-03-01 15:20

本文关键词： 转发策略车联网 NDN网络 NS-3　出处：《吉林大学》2017年硕士论文　论文类型：学位论文

【摘要】：汽车在人们的生活中一直扮演着非常重要的角色,并且由于物联网的快速发展和人们对于汽车的需求从单一的驾驶功能向多元化服务的转变,因此车联网的概念被提出,而车联网的核心,在于如何更高效率的获取数据上。IP网络由于自身的局限性,可以预见,在将来很难完美地支持车联网所提出的各种技术要求。而NDN网络独特的路由方式,可以很好的适用于车联网通信。NDN网络只关心获取的数据正确与否,而不关注如何获得数据和从哪里获得数据。而且NDN网络具有路由缓存功能,数据可以按照不同的替换策略存储到路由中,所以数据可能存储在多个路由节点中,大大提高了数据的获取效率,并且这种数据的分布方式也符合车联网通信方式。在车联网下,车辆在运行过程中,可以直接从邻居车辆中得到需要的数据,而不必从数据的源头获得,从而减少了路由转发次数,节省了时间,提高了通信效率。但NDN网络仍需要解决很多问题。一方面,洪泛广播策略会导致大量的信息丢失和过高的重传开销,这给网络造成了很大的负担。另一方面,由于车辆位置的不断变动,导致拓扑结构不断的变化,车辆可能会处于断网的情况,因此降低了重传效率。本文首先提出了基于距离的转发策略,根据节点到达最终目标地点距离的不同,设置不同的转发等待时间。距离越短,转发等待时间越短。当某个节点在等待广播的过程中,收到了来自其他节点的相同的兴趣包,说明有节点已经广播了此兴趣包,因此不再重复广播。这个策略很好地解决了洪泛广播和兴趣包命中率问题,但平均延迟较高。本文又提出了“受欢迎度”这个概念,“受欢迎度”代表了每个节点所携带数据受欢迎的程度。从车辆节点所携带的数据这个角度入手,设计了基于“受欢迎度”的转发策略,在对兴趣包是否重传的判断中,“受欢迎度”策略不仅保证了信息传输的效率,而且成功地降低了平均延迟时间。为了分析本文设计的转发策略的性能,利用NS-3仿真平台下的ndn SIM模拟器,仿真了真实的道路环境和物理环境,模拟了车辆的运行轨迹和通信。实验结果表明,在NDN网络的V2V通信下,本文所设计的转发策略比原有的转发策略更好地适用于车辆之间的通信。
[Abstract]:Automobile has always played a very important role in people's life, and because of the rapid development of Internet of things and the change of people's demand for automobile from single driving function to diversified service, the concept of car networking has been put forward. The core of vehicle networking is how to obtain data more efficiently. IP network, due to its own limitations, can foresee that it will be difficult to support all kinds of technical requirements of vehicle networking perfectly in the future. However, NDN network has a unique routing mode. It can be well applied to the vehicle-networking communication. NDN network only cares about whether the obtained data is correct or not, but not about how to get the data and where to get the data. Moreover, the NDN network has routing caching function. Data can be stored in routing according to different replacement policies, so data may be stored in multiple routing nodes, which greatly improves the efficiency of data acquisition. And the distribution of the data is in line with the vehicle network communication mode. Under the vehicle networking, the vehicle can get the needed data directly from the neighbor vehicle during the running process, without having to obtain the data from the source of the data. Thus reducing the number of routing forwarding, saving time and improving communication efficiency. However, NDN network still needs to solve many problems. On the one hand, flood broadcast policy will lead to a large number of information loss and high retransmission overhead. This places a heavy burden on the network. On the other hand, because of the continuous changes in the location of the vehicle, resulting in continuous changes in the topology, the vehicle may be in a situation where the network is cut off. Therefore, the efficiency of retransmission is reduced. Firstly, a distance-based forwarding strategy is proposed in this paper. According to the different distance between the nodes to the final destination, different forwarding waiting times are set. The shorter the distance is, the shorter the forwarding time is. The shorter the forwarding wait time. When a node receives the same packet of interest from other nodes while waiting for broadcast, indicating that some node has already broadcast the packet of interest, This strategy is a good solution to the problem of flooding and interest packet hit ratio. But the average delay is high. This paper also proposes the concept of "popularity", which represents the degree of popularity of the data carried by each node, starting from the point of view of the data carried by the vehicle node. In this paper, we design a forwarding strategy based on "popularity". In judging whether interest packets are retransmitted or not, the "popularity" strategy not only ensures the efficiency of information transmission, but also improves the efficiency of information transmission. In order to analyze the performance of the forwarding strategy designed in this paper, the real road environment and physical environment are simulated by using the ndn SIM simulator based on NS-3 simulation platform. The simulation of vehicle trajectory and communication shows that the proposed forwarding strategy is more suitable for vehicle communication under V2V communication in NDN network than the original forwarding strategy.
【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U495;TN929.5

【相似文献】