Forwarding And Cache Strategies For V2X Communication Via Named Data Networking

With the rapid development of transportation and automobile manufacture,traffic jams and safe driving have been attracting more and more attention.VANETs(Vehicular Ad Hoc Networks)connecting vehicles,roadside units and Internet together,give a new definition to modern traffic.Under the condition of high mobility and rapidly changing network topology,IP-based VANETs will easily result in short-lived and intermittent connectivity.NDN(Named Data Networking)using named data instead of IP address,which has obvious advantages in the VANETs because of its characteristics of the data cache and multiple sources.However,the scenario in current strategies about caching and forwarding is too simple,which does not take full consideration of node mobility and broadcast characteristics in VANETs.Considering the effectiveness and efficient requirements of communication,in this paper,we design data forwarding and caching strategies under NDN,which is converged with VANETs architecture.In terms of data forwarding,according to the characteristics of the data in VANETs,this paper designs a hybrid forwarding strategy combining opportunistic-based with probabilistic-based forwarding,which also introduces retransmission and confirmation mechanisms that will ensure the network performance in VANETs.Simulation results from NS3 and SUMO demonstrate that the proposed forwarding strategy outperforms the state-of-art schemes,such as the IP network and R-NDN,with less end-to-end delay and overhead.In terms of caching strategies,there is a greatly difference in a wireless VANETs,in which the cache decision-making occurs among all the nodes under the broadcasting path.Considering the contradiction between finite capacity and infinite cached contents,a kind of distributed caching strategy is proposed using the broadcast nature of wireless channel,which will optimize cache content distribution in VANETs.Compared to the traditional caching scheme LCE(Leave Copy Everywhere),this algorithm reduces the average hop count with high content hit rate.