Research On Collaborative Content Delivery Mechanism Of Dual-Structural Information-Centric Networking

Named Data Networking(NDN)is a representative research scheme of Information Content Networking(ICN).In order to reduce bandwidth and improve the transmission efficiency,NDN adopts in-network cache technology.However,NDN is driven by user,lacking of push capability.Combining the"one to many" content delivery mode of broadcast,broadcast-storage networking can actively push the popular content to the edge server in advance,which further enhances the transmission performance of popular content.In view of this,this thesis puts forward the Dual-Structural Information-Centric Networking(DSICN)with NDN as primary structure and broadcast-storage networking as secondary structure through introducing the broadcast-storage networking to the edge of NDN.As the interchange of DSICN primary and secondary structures,convergence gateway adds the delivery of broadcast content on the basis of NDN content delivery.The difference between the two delivery methods makes the traditional content delivery method hard to be applied to DSICN.Therefore,given the new characteristics of DSICN,how to design efficient content delivery mechanism,aiming at improving content delivery efficiency is the focus to be solved in this thesis.For the analysis of the difference of broadcast content and content chunk,a content delivery model of DSICN is firstly established.Then,in view of the demand characteristics and relation of the two kinds of content,a collaborative content caching algorithm based on gray prediction model(GPM-CCCA)is presented to solve the problem of content cache in content delivery.On this basis,a collaborative content delivery algorithm based on neighbor collaboration(NC-CCDA)is presented to figure out the problem of content delivery.The specific work of this thesis is as follows:(1)Given the characteristics of content delivery in DSICN,the algorithm GPM-CCCA is designed to provide the basis for the collaborative delivery of content.Considering the existing content access information in the convergence gateway,GPM-CCCA calculates the weight of the hot content in different time periods,and predicts user's future access trend,using grey predict model.According to this,the relation of the two kinds of content is to be used to realize the cooperative caching of them by establishing the association mechanism of unified content identification.The algorithm greatly relieves the redundant cache of content,and improves the utilization rate of the cache space.(2)Based upon the collaborative content caching,the algorithm NC-CCDA is proposed to solve the problem of content delivery in DSICN.Given the difference of the broadcast receiving capability of the convergence gateway,the algorithm uses the neighbor cache information table to record the broadcast content of the neighbor convergence gateway and realizes the cooperative delivery of the broadcast content of the multiple convergence gateways by distributing the notification message in real time.On this basis,the content forwarding method based on neighbor collaboration is designed by establishing the transformation mechanism of two kinds of content.Compared with the traditional content delivery algorithm,NC-CCDA algorithm avoids the redundant delivery of broadcast content among multiple convergence gateways and realizes the efficient use of two kinds of content.(3)Based on the above research,a DSICN content delivery prototype system was developed.The GPM-CCCA algorithm and the NC-CCDA algorithm are validated and analyzed by using the real content of DSICN.The experimental results show that,compared with delivery method of broadcast-storage networking,the GPM-CCCA algorithm has higher sharing efficiency,and the NC-CCDA algorithm has a higher cache hit rate and lower response delay.