Channel-Aware Device-to-Device Pairing for Collaborative Content Distribution

With the increasing penetration of smart devices, device-to-device (D2D) communications offer a promising paradigm to accommodate the ever-growing mobile traffic and unremitting demands. The redundant storage and communication capacities of smart devices can be exploited for collaborative content caching and distribution. In this work, we study the D2D pairing problem, which appropriately pairs a device requesting a content file with a nearby device which caches the requested file. First, we formulate the D2D pairing problem as an integer linear program (ILP). Due to the complexity of the problem, we further develop a heuristic channel-aware D2D pairing algorithm. Computer simulations are conducted to compare the channel-aware algorithm with the optimal solution, as well as a minimum distance-based algorithm and a random algorithm. We consider both the static scenario and the dynamic scenario with arrivals and departures of requesting and caching devices. The simulation results demonstrate that the channel-aware algorithm outperforms the random algorithm in terms of the total number of served D2D pairs and the average latency of served pairs.