FedTrans: Efficient Federated Learning via Multi-Model Transformation
Yuxuan Zhu, Jiachen Liu, Mosharaf Chowdhury, Fan Lai
TL;DR
FedTrans tackles the challenge of heterogeneity in federated learning by automatically generating and training a suite of models of varying complexity for individual clients. It introduces a three-component framework—Model Transformer to morph bottleneck Cells, Client Manager to assign models via a utility-based, data-aware scheme, and Model Aggregator to softly share weights across models—to balance accuracy and training cost. Empirical results across four datasets show substantial per-client accuracy gains (up to 72%) and large cost reductions (up to 20x) compared to state-of-the-art multi-model FL methods, demonstrating strong scalability and practical impact for hardware-aware FL. The approach reduces manual model exploration and extends FL applicability to highly diverse client environments.
Abstract
Federated learning (FL) aims to train machine learning (ML) models across potentially millions of edge client devices. Yet, training and customizing models for FL clients is notoriously challenging due to the heterogeneity of client data, device capabilities, and the massive scale of clients, making individualized model exploration prohibitively expensive. State-of-the-art FL solutions personalize a globally trained model or concurrently train multiple models, but they often incur suboptimal model accuracy and huge training costs. In this paper, we introduce FedTrans, a multi-model FL training framework that automatically produces and trains high-accuracy, hardware-compatible models for individual clients at scale. FedTrans begins with a basic global model, identifies accuracy bottlenecks in model architectures during training, and then employs model transformation to derive new models for heterogeneous clients on the fly. It judiciously assigns models to individual clients while performing soft aggregation on multi-model updates to minimize total training costs. Our evaluations using realistic settings show that FedTrans improves individual client model accuracy by 14% - 72% while slashing training costs by 1.6X - 20X over state-of-the-art solutions.
