| TCP/IP-based network is difficult to adapt to vehicle-mounted high-speed mobile environment due to insufficient consideration of supporting mobility at the beginning of the design.TCP/IP-based network becomes a bottleneck restricting the development of VANET and in-car entertainment.In order to solve high delay and instability of the existing vehicle entertainment system,this paper research NDN’s basic principle,NDN’s application scenarios in VANET,clustering partitioning algorithms,related technologies of video transmission,etc.The main research contents and innovation points are as follows:(1)This paper proposes the idea of applying NDN to VANET based on in-depth research of NDN’s basic principle and VANET’s characteristics.NDN-based VANET can replace traditional TCP/IP-based VANET.NDN has natural support for mobility,adapts to the high-speed moving environment of VANET,and builds stable communication connections between vehicles.(2)In view of the changing topology of VANET,and the intermittent connection of vehicles,traditional NDN cache strategy is difficult to obtain the global optimal solution.This paper proposes Cluster-based Partition Cooperation Caching Strategy based on in-depth research of existing NDN cache strategies and the k-means clustering partition algorithm.The experimental results show that when the node cache capacity is 300 Chunk and 700 Chunk,cache hit ratio of proposed strategy is 7.1%and 9.4% higher than that of other strategy,respectively;time delay of proposed strategy is 10.3%and 18.4% lower than that of other strategy,respectively;average hop count of proposed strategy is13.6% and 8.3% lower than that of other strategy,respectively.Proposed strategy can effectively shorten the time for nodes to obtain required data in VANET.(3)In view of high time delay and instability of current vehicle entertainment system,this paper designs and implements an NDN-based car video entertainment system based on NDN’s architecture and the proposed cache strategy.This system is divided into two parts,the on-board client and the VANET management system.It has many functions,such as resource uploading,video playing,user sharing,etc.Compared with existing video entertainment systems,this system is significantly improved in terms of resource search speed and network delay and can effectively improve the quality of in-car video entertainment. |
