Optimal Design For Content Delivery Network

Content delivery network(CDN)deploys replica servers at the network edge or core switching area,which can significnatly reduce the content access latency.Therefore,this reaserch focuses on the optimization of replica server deployment and content caching in CDN.Firstly,we propose an optimization strategies for the replica server placement and network resource allocation.To verify the efficiency of the proposed stategies,a mixed integer linear programming(MILP)is constructed,and efficient heuristic algorithms for replica server placement and network resource allocation are proposed.The simulation results show that the proposed replica server placement and network resource allocation algorithms can effectively reduce the average content delivery latency,and meanwhile achieve the load balance on each content server.Secondly,based on the characteristics of the content access frequency that follows the Zipf distribution,an efficient content caching strategy that store the contents with high access frequency at the local server is proposed.An integer linear programming(ILP)model and the corresponding heuristic algorithm are also proposed.The results show that the proposed caching strategy can effectively reduce the average content delivery latency.