Researches On Cache Strategy In Information-Centric Vehicular Network

Vehicle Ad Hoc Network(VANET)is a new technology,which has been widely used in intelligent vehicle transportation systems in recent years.It provides effective means for vehicle node environmental information perception,road safety early warning,data acquisition and information distribution,which has broad development prospects.However,the current development of the Internet of Vehicles also faces many challenges.On the one hand,due to the binding of identity and location,the traditional TCP/IP network architecture is not suitable for VANET with highly varying topology.On the other hand,information such as road safety and entertainment transmitted on the network is irrelevant to the carrier of the content.Therefore,we integrate ICN into VANET to optimize the overall performance of the network.Based on the analysis of ICN’s embedded cache strategy,this article has conducted an in-depth analysis on how to improve the cache redundancy in the network while increasing the cache hit rate of hot content.Based on this,we propose a caching strategy based on two-way selection of RSU and vehicle,which is mainly divided into two phases:1)pre-caching phase,the roadside unit constructs a decision tree based on historical interest request data,and accordingly caches the appropriate hotspot content in the appropriate RSU infrastructure in advance;2)In the R2V phase,in order to solve the problem of limited communication with RSU and cache redundancy in vehicle-intensive scenarios.We divide the vehicles in the road into different logical clusters according to the interest requests.At the same time,we use the three-phase traffic flow theory and real city datasets to analyze the relationship between the micro-motion state of the vehicle and the network stability.RSU chooses relatively stable nodes in the cluster to cache hot content to achieve the purpose of improving content distribution efficiency and reducing network load.Finally,the performance and simulation of the algorithm performance are carried out by using NS-3 and SUMO simulation platform.The results show that the proposed strategy has good performance in terms of average access delay,average hop count and cache hit ratio compared with the existing strategy.