An Edge Caching Strategy for Minimizing User Download Delay

Abstract

In the scenario with many small base stations (SBSs) deployed, edge caching technology could bring contents closer to users by caching files at SBSs. Considering these SBSs with limited storage capacity, how to effectively cache files is a difficult and interesting problem. Many factors should be considered, such as the popularity of files, user download delay and average hit rate. In this paper, we investigate this problem and propose a minimizing user download delay caching (MUDDC) algorithm. It decides which files should be cached and where to cache them for reducing download delay. There is a conflict between hit rate and download delay with the limited SBS storage capacity. We target the average user download delay and model an optimization problem with the constraint of average hit rate and find the optimal solution. The simulation results show that the system performance is improved.