CoeF-SFL: Preserving Collaborative Server-Client Learning with Enhanced Communication Efficiency
This study addresses the high communication overhead and optimization objective misalignment caused by auxiliary networks in split federated learning by proposing the CoeF-SFL framework. This method substantially reduces communication costs through single data exchange per round and gradient reuse, while eliminating auxiliary networks to preserve end-to-end optimization objectives. Furthermore, it introduces a curvature-based gradient compensation mechanism that leverages diagonal Hessian approximation and Jacobian-Hessian surrogate losses to correct stale gradients within the activation space. Experimental results demonstrate that the proposed framework significantly outperforms existing methods across both vision and language tasks. The source code has been made publicly available.