Video Cooperative Caching in High-Speed Train by using Differential Evolution Algorithm

In this paper, we introduce a model of cooperative caching to shorten transmission time of video in specific scenario such as high-speed railway. When user terminals (UTs) request for videos from the intelligent routing relay (IRR), in order to reduce the waiting time of UTs, IRR splits the video into several segments and assigns cooperative caching tasks to UTs which are willing to accept the tasks. The UTs can cache the segments with their cellular network traffic and upload these segments to IRR for combination. IRR prefers to cache the beginning 10 seconds video firstly, as UTs can start watch video while caching the rest segments. In order to minimize the video transmission time, we use differential evolution (DE) algorithm to allocate segments to UTs. Simulation results verify the effectiveness of DE and show that the performances of DE are better than random allocation (RA) and average allocation (AA) strategy.