A review of federated learning: architectures, challenges, and targeted solutions

Federated Prompt Learning: A Unified Framework, Empirical Analysis, and Future Directions

Large language models (LLMs) have become core components of cloud-based intelligent services in academia and industry, yet their training and deployment are hindered by high computational costs, data centralization, and privacy concerns. Federated learning (FL) offers a decentralized training paradigm that enables clients to collaboratively train a learning model without sharing raw data, making it a promising solution for privacy-preserving LLM training and reasoning. This paper presents a comprehensive survey of federated prompt learning (FPL) to review recent advances in integrating the federated learning paradigm and large language models, answering the following research questions: RQ1: The fundamental motivations, characteristics, and enabling technologies of FPL, and how it differs from conventional FL and full-model federated fine-tuning; RQ2: The trade-offs FPL approaches exhibit in performance, communication efficiency, computational overhead, scalability, personalization, and heterogeneity handling; RQ3: The remaining security, privacy, robustness, and system challenges, along with key future research directions. To this end, we systematically examine existing FPL methods across the full model lifecycle: pre-training, fine-tuning, and practical applications, while discussing security, privacy, and robustness issues and summarizing existing defense mechanisms. Finally, we highlight open challenges and future directions, aiming to help readers understand how the insights drive research in FPL.

Federated Learning Meets Test-Time Adaptation: Methods, Challenges, and Future Directions

Federated Learning for Large Language Models: Opportunities, Challenges, and Open Research Directions

Federated MLOps: Secure CI/CD for Distributed Model Training and Deployment

Federated Machine Learning (FL) has emerged as a promising approach for collaborative model training without sharing raw data, thereby preserving privacy. However, integrating FL with modern MLOps practices poses unique challenges in automating and securing the Continuous Integration and Continuous Deployment (CI/CD) pipelines. This paper proposes Federated MLOps, a framework that combines CI/CD principles with federated model training to enable secure, automated, and efficient deployment of distributed ML models. We describe the system architecture, security mechanisms, and pipeline orchestration strategies, and demonstrate the framework through a case study evaluating performance, scalability, and privacy preservation. Our results highlight the potential of Federated MLOps to enhance model reliability, reproducibility, and security in distributed learning environments.

A Study on Federated Learning Techniques for Privacy Preservation

An in-depth analysis of federated learning methods and paying special attention to the issue of privacy is provided, which examines new developments, concerns and tradeoffs connected with privacy, effectiveness of communication, model noise, and scalability of systems.

FL-OA: A Byzantine-Robust Federated Learning Framework with Outsourced Auditing for Intelligent Devices

Federated learning (FL) enables multiple intelligent devices to collaboratively train a high-accuracy model without sharing raw data. However, due to its distributed nature, FL is vulnerable to Byzantine attacks. Existing defense methods rely on strong assumptions, such as the proportion of malicious devices not exceeding 50\%, or the server having an additional root dataset that matches the training task. Moreover, they show limited efficacy as they overlook $(i)$ the divergence among benign updates and $(ii)$ the curse of dimensionality involved in comparing two high-dimensional updates. To solve these concerns, we propose FL-OA, a Byzantine-robust federated learning framework utilizing outsourced auditing. In FL-OA, the server collaborates with third-party organization that holds an additional root dataset to perform outsourced auditing, thereby enabling the server to achieve robust aggregation without strong assumptions. Additionally, FL-OA introduces a gradient ascent step and a correction term during local training to mitigate the divergence among benign updates, and designs a parameter importance indicator to extract critical parameters for auditing, alleviating the curse of dimensionality. We further provide a detailed theoretical analysis of FL-OA. Extensive experiments demonstrate that FL-OA outperforms existing defense methods against Byzantine attacks.