VANET中基于车辆分簇的协作缓存策略

Cooperative Caching Strategy Based on Vehicle Clustering in VANET

随着智能交通系统的发展,移动车辆不仅需要地图信息,还需要更多娱乐内容,而整个网络的容量是有限的,这给车载自组织网络带来很大的压力。边缘缓存是在系统的边缘部署缓存,在车载自组织网络中引入边缘缓存技术,可以有效地缓解网络的压力。对车载自组织网络中的缓存策略进行了研究,提出了一种基于车辆分簇的协作边缘缓存策略,可以充分利用车载自组织网络中有限的缓存资源,内容可以缓存在移动车辆和路边单元中,移动车辆可以从簇头和路边单元获取所需内容,不同的内容获取方式会带来不同的请求时延。由于移动车辆和路边单元的缓存容量是有限的,为了降低内容请求时延和成本,构建了一个时延和成本联合最小化的优化问题,并采用蚁群算法对该问题进行求解,以得到最优的缓存放置方案。仿真结果表明,该算法拥有很好的性能。

With the development of intelligent transportation system,mobile vehicles will need not only map information,but also more entertainment content,but the capacity of the entire network is limited,which brings great pressure to the vehicular ad hoc network(VANET).Edge caching is the deployment of caches on the edge of the system,introducing edge caching into VANET can effectively relieve the pressure of the network.A collaborative edge caching strategy based on vehicle clustering is proposed,which can make full use of the limited caching resources in VANET,contents can be cached in mobile vehicles and roadside unit(RSU),mobile vehicles can get requested contents from cluster head and roadside unit,and different ways to get contents will bring different delay.Considering the limited cache capacity of moving vehicles and roadside unit,an optimization problem is constructed to minimize the delay and cost and solved by the ant colony algorithm to obtain the optimal cache placement scheme.The simulation shows that the proposed algorithm is efficient.