Cooperative Caching And Routing Strategy Based On Regional Centralized Storage In Content Centric Networking

With the continuous expansion of the scope and scale of Internet applications,the host-centric communication mode of "host to host" has been unable to meet the acquisition and distribution of massive content in the future.Therefore,Content Centric Networking(CCN)came into being.CCN's ubiquitous caching and content-based routing mechanism avoid redundant transmission of heavy traffic and have high data distribution efficiency.Routing forwarding and caching strategies are also key technologies and research hotspots of CCN.At present,CCN traditional flood forwarding and local caching strategies restrict routing forwarding efficiency and cache resource utilization.In order to further improve the overall network performance,this thesis designs and develops two aspects of routing and caching.The main research contents are as follows:Aiming at solving the problem of low transmission efficiency that the uncertainty of traditional routing strategy forwarding causes,a routing strategy is proposed which is based on regional centralized storage.Firstly,a centralized storage scheme is proposed.According to the node attributes,each region in the scheme selects the core nodes which are centrally stored in the region,and the ordinary nodes are only responsible for routing and forwarding.Then,a routing strategy based on regional centralized storage is designed for regional user requests,to be quickly forwarded to the regional core node for content search and retrieval.The centralized storage solution saves the actual deployment cost of the network,reduces the network cache operation overhead,and combines with the routing strategy to effectively control redundant traffic and improve routing efficiency.The simulation shows that compared with typical strategies,the strategy can greatly reduce network load,improve the performance of cache resource utilization and user experience under the lower network overhead.Aiming at solving the problem of high cache redundancy and low cache resource utilization in the CCN cache strategies,a collaborative cache strategy based on content popularity and cache revenue is proposed under the proposed centralized storage scheme.Firstly,the access node performs periodic real-time statistics on the local popularity of the content,and then aggregates it to the regional core node for content global popularity calculation.When the data packet returns,the regional core node combines content popularity and cache revenue,and performs optimal cache decision in the way of neighborhood coordination,controlling redundancy while preserving the high popularityor high-yield content of the domain.This strategy maximizes the efficiency of cache space by filtering the contents of the area cache effectively.The simulation results show that the proposed strategy has better network performance compared with typical strategies in terms of caching hit ratio,request delay and server load.