Proactive Caching in 5G Small Cell Networks

Massive deployment of small cell base stations (SBSs) is going to play a key role for capacity and coverage enhancements in 5G networks. However, the backhaul for these networks remains an important issue. Ideally, the capacity of backhaul has to be of the same order as wireless links in order to avoid bottlenecks in the delivery and sustain the huge traffic generated by mobile users, especially due to video streaming and content sharing in social networks. In reality, the deployment of such high‐speed backhauls is not straightforward due to its costly nature. Thus, one promising way of tackling this backhaul bottleneck and satisfying users' demand is to cache strategic content at the edge of the network, namely at the SBSs and user terminals. So far, most solutions have been based on the reactive networking paradigm, in which users' content requests are served immediately upon their arrival, causing outages otherwise. In this chapter, we first provide an overview of recent research in small cell networks (SCNs), and then explore the novel paradigm of proactive caching in SCNs, which leverages the latest developments in storage, context‐awareness, and social networking. With this approach, we show that important gains can be obtained, with backhaul offloading and higher ratios of satisfied users reaching to 22% and 26%, respectively.