Energy-Efficient Multicast/Unicast Edge Caching for Dense Small Cell Networks with Graph Theory

摘要

Local caching of popular content files at the wireless edge is a promising way to address several challenges for the next mobile radio generation. Apart from reducing latency, it also helps save energy and better control the available end-to-end power budget. In this paper, we take advantage of dense small cell networks' architecture to further reduce the power consumption of the system, using a graph-theoretic approach. The basic idea is to download the requested content file from a neighboring small cell rather than macro cell or backhaul, if it is not cached at the serving base station. More precisely, we build a graph to fetch the requested content file from the nearest less power consuming small cells. Special attention is paid to the adequate number of small base stations involved in the graph to ensure an energy efficient solution. In addition, we apply our graph theory based approach to multicast transmissions and show that our built graph outperforms the conventional unicast/multicast caching transmission in terms of energy efficiency. Simulation results also showed the effectiveness of our approach for different cache size and steepness parameter.