For those interested or confused around federated learning, I suggest skimming the 2019 paper "Advances and Open Problems in Federated Learning" [0]. The introduction is quite good and the table of contents gives a good overview of the current challenges in the field.<p>From the paper, "Federated learning is a machine learning setting where multiple entities (clients) collaborate in solving a machine learning problem, under the coordination of a central server or service provider. Each client’s raw data is stored locally and not exchanged or transferred; instead, focused updates intended for immediate aggregation are used to achieve the learning objective."<p>0: <a href="https://arxiv.org/abs/1912.04977" rel="nofollow">https://arxiv.org/abs/1912.04977</a>