Knowledge distillation has caught a lot of attention in Federated Learning (FL) recently. It has the advantage for FL to train on heterogeneous clients which have different data size and data structure. However, data samples across all devices are usually not independent and identically distributed (non-i.i.d), posing additional challenges to the convergence and speed of federated learning. As FL randomly asks the clients to join the training process and each client only learns from local non-i.i.d data, which makes learning processing even slower. In order to solve this problem, an intuitive idea is using the global model to guide local training. In this paper, we propose a novel global knowledge distillation method, named FedGKD, which learns the knowledge from past global models to tackle down the local bias training problem. By learning from global knowledge and consistent with current local models, FedGKD learns a global knowledge model in FL. To demonstrate the effectiveness of the proposed method, we conduct extensive experiments on various CV datasets (CIFAR-10/100) and settings (non-i.i.d data). The evaluation results show that FedGKD outperforms previous state-of-the-art methods.

该论文提出一种名为FedGKD的新方法，通过融合历史全局模型的知识进行本地训练，解决异构联邦学习中的客户端漂移问题，并在各种计算机视觉和自然语言处理数据集上进行广泛的实验和评估，达到了优于其他五种方法的结果。

异构联邦学习中的局部全局知识蒸馏与非独立同分布数据