Collaborative hierarchical caching for traffic offloading in heterogeneous networks

To address the challenge arising from mobile users' increasing demands for multimedia services, applying content caching in heterogeneous networks (HetNets) is regarded as an effective way to offload traffic and improve the capacity of mobile networks. In this paper, we aim at designing novel content caching strategies in HetNets to offload the network traffic and support users' requests locally. Specifically, based on some practical network constraints (i.e., patterns of user requests, link capacity and heterogeneous cache sizes) and the derived network topology, we propose a low-complexity and practicable distributed collaborative hierarchical caching framework by decomposing the formulated large-scale optimization problem into a series of simpler subproblems. Trace-based simulation results demonstrate the effectiveness of the proposed framework.