Research On Edge Cooperative Caching Mechanism For Heterogeneous Networks

With the rapid development of wireless technology,the demand of obtaining file content through wireless network is increasing rapidly.However,for the popular contents,especially video contents,when users obtain the popular contents from the remote servers,there will be a large number of repeated transmission,and it will cause the waste of resources.Moreover,it will cause network congestion,reduce the quality of user service and increase energy consumption.How to offload the traffic effectively has become a common concern of academia and industry.In response to solving this challenge and realizing the green communication,caching is an effective means.It allows the popular content cached in the place where is close to the user terminal,such as base stations.When the contents of user requests are cached in the base stations,it can be obtained directly from the base stations,rather than through the core network to the remote servers.This reduces the burden of the network greatly.Firstly,this paper introduces the architecture of mobile network,and points out the problems faced by users in requesting contents.Then the edge caching mechanism is introduced,as well as the heterogeneous network.Then this paper puts forward the cooperative caching mechanism based on the joint optimization of the caching and transmission.The storage space of the small base stations is divided into two parts,and one is used for caching the contents which are from the remote servers ahead of the requesting time,and the other is used for storing the contents of the upcoming wireless transmission.By allocating the proportion of two parts of the caching space to minimize the network energy consumption,and it finally obtains that the optimal proportion for caching queue of wireless transmission is 1%.Based on the above research results,to further improve the efficiency of the caching,cooperative caching mechanism based on heterogeneous network is put forward.When considering the content popularity,this problem is a NP-hard problem.In order to solve the problem effectively,heuristic simulated annealing algorithm is put forward.Based on the process of user requests the content and the corresponding energy consumption,effective strategy of base station caching configuration is designed.Simulation results show that this method can reduce the energy consumption of network system and realize the purpose of green communication.