Design And Implementation Of Collaborative Caching Algorithm For NDN

With the rapid development of Internet information services, content distribution and subscription gradually become a major part of the network application services in recent years. The design principle of the Internet is to complete the end-to-end communications, which is not efficient for the content distribution. Therefore, the research of information-centric network emerges both by the push of networking technologies and pull of users.This paper first describes the research background of the Named Data Network (NDN) and analyzes the NDN network architecture, including its architecture principles and the key technologies. Based on this,it summarizes the state of the related research, and the existing problems, especially problems in the cache strategies. Then it studies the NDN caching strategies, summarizing the main factors affecting the caching efficiency, and the effect of content forwarding on caching collaboration. Subsequently, the paper analyzes the main problems in the existing caching strategies.To resolve the major problems existing in the current NDN caching collaborative strategies, a Collaborative Cachingalgorithm based on Neighbor Routing information (NRCC) for NDN is proposed. By sharing caching information in the network, NRCC can help routers learn caching information in neighboring routers to prevent caching the same content already cached in neighboring nodes. This algorithm enables more different content caching in routers which improves the caching hit ratio. Moreover, NRCC can help routers exploring the surrounding neighbors whether they have already cached the target content, which can reduce the number of data forwarding hopsand reduce the average delay for accessing contents. This strategy can also reduce the frequency of cache replacement and improve the network-wide average caching hit ratio, and therefore reduce the average server load. At the same time,the strategy can help the copies of the contents to be spread to the edge of network, which can reduce the load of backbone network and achieve network load balance.Finally, simulation scenarios are implemented under ndnSIM based NS3 to evaluate the performance of the algorithm. The simulation results show that the algorithm helps improve the network caching efficiency and reduce the data distribution delay.