Federated Large Language Models: Current Progress and Future Directions
To address the convergence difficulties and high communication overhead of large language models (LLMs) in federated learning (FL) caused by data heterogeneity, this paper introduces FedLLM—the first unified analytical framework for LLMs in FL. It systematically surveys two dominant paradigms: federated fine-tuning and federated prompt learning, while rigorously analyzing core challenges including data heterogeneity, communication efficiency, and privacy preservation. The work identifies promising future directions—namely, federated pre-training and LLM-augmented FL—and fills a critical gap in systematic literature review. A multidimensional taxonomy and evaluation framework is established to clarify key technical bottlenecks. Integrating insights from FL, LLM adaptation, prompt engineering, distributed optimization, and privacy-preserving computation, this study delivers a practical, robust, and privacy-aware methodology for deploying LLMs in real-world federated settings. (149 words)