Toward Smart and Cooperative Edge Caching for 5G Networks: A Deep Learning Based Approach

The emerging 5G mobile networking promises ultrahigh network bandwidth and ultra-low communication latency (<1ms), benefiting a wide range of applications, including live video streaming, online gaming, virtual and augmented reality, and Vehicle-to-X, to name but a few. The backbone Internet, however, does not keep up, particularly in latency (>100ms), due to its store-and-forward design and the physical barrier from signal propagation speed, not to mention congestion that frequently happens. Caching is known to be effective to bridge the speed gap, which has become a critical component in the 5G deployment as well. Besides storage, 5G base stations (BSs) will also be powered with strong computing modules, offering mobile edge computing (MEC) capability. This paper explores the potentials of edge computing towards improving the cache performance, and we envision a learning-based framework that facilitates smart caching beyond simple frequency- and time-based replace strategies and cooperation among base stations. Within this framework, we develop DeepCache, a deep-learning-based solution to understand the request patterns in individual base stations and accordingly make intelligent cache decisions. Using mobile video, one of the most popular applications with high traffic demand, as a case, we further develop a cooperation strategy for nearby base stations to collectively serve user requests. Experimental results on real-world dataset show that using the collaborative DeepCache algorithm, the overall transmission delay is reduced by 14%∼22%, with a backhaul data traffic saving of 15%∼23%.