Research On Joint Content Recommendation And Caching System For Mobile Edge Networks

How to effectively distribute mass content data is a huge challenge for mobile communication networks.The mobile edge computing technology can exploit the widely distributed mobile edge infrastructure,such as base station(BS),to cache and distribute content,which can effectively increase the distribution capacity and relieve the congestion of the core network and the bearer network.This paper proposes a novel edge computing application called joint content recommendation and caching system,or explicit BS caching system.This system organically combines content recommendation technology,distributed BS caching,and cross-layer wireless communication technology to actively cache content that may be of interest to local users in BSs and present the content to users for browsing and downloading.Compared with the traditional implicit BS caching system,the explicit BS caching system proposed in this paper has the advantages of large capacity and good scalability.This paper explains the architecture of the explicit BS caching system,designs pivotal content caching algorithms,and conducts a comprehensive analysis of its system performance.The main research contents and contributions of this paper include two parts.First,the performance of a single BS explicit caching system is studied.Based on the typical single BS network environment and content distribution context,this paper aims to maximize the quality of user experience(QoE),and model the single BS explicit caching problem as a nonlinear 0-1 integer programming problem.The optimal algorithm and heuristic algorithm are designed.In addition,the theoretical performance bound of the system is deduced based on the simplified scenario model,and the effect of cross-layer information and key system parameters on system performance is analyzed through simulation.Second,expanding from single BS scenario to multi BSs scenario,this paper further studies the performance of the multiple BSs cooperative caching system.Based on multiple BSs system interference model,multi-user random walk model and considering the optimization of backhaul network between base stations,this paper studies the optimization problem of multiple BSs cooperative caching and updating,and proposes an optimal algorithm and a heuristic algorithm based on the linearization of optimization problems.The simulation results show that application layer and link layer information are the key to the performance of the explicit BS caching system,while physical layer information has limited impact on system performance.Compared with single BS caching,the multiple BSs cooperative caching system can make better use of BS storage resources and backhaul network resources.The research in this paper shows that explicit BS caching system can effectively guarantee user QoE through cross-layer information interaction and multiple BSs cooperation mechanisms.It is a novel type of content recommendation and distribution system with broad application prospects.