Wireless Caching in Large-Scale Edge Access Points: A Local Distributed Approach

Today's mobile users achieve unsatisfactory quality of experience mainly due to the large network distance to the centralized infrastructure. To improve users' experiences, caching at the wireless access points (APs) has been proposed for bringing the contents closer to users. However, the wireless content placement is challenging as the placement is affected by many realistic constraints, such as a large number of APs, interaction among neighboring APs, various local content popularities. In this paper, we study the wireless caching problem, i.e., which contents should be stored by which APs. First, we fulfil these constraints to formulate our problem and introduce an objective function that maximizes the total cache hit rate of all APs. Next, we prove the NP-hardness of the problem and propose a local distributed caching algorithm to address it. Furthermore, we provide a game theoretic perspective on the problem and prove that the proposed algorithm can converge to the Nash Equilibrium in polynomial time. Finally, we perform simulations on a real-world dataset to demonstrate the effectiveness of our algorithm.