Journal of Computer Applications ›› 2025, Vol. 45 ›› Issue (3): 856-863.DOI: 10.11772/j.issn.1001-9081.2024030296

• Cyber security • Previous Articles     Next Articles

Lazy client identification method in federated learning based on proof-of-work

Haili LIN, Jing LI()   

  1. School of Computer Science and Technology,University of Science and Technology of China,Hefei Anhui 230027,China
  • Received:2024-03-20 Revised:2024-04-12 Accepted:2024-04-16 Online:2024-04-24 Published:2025-03-10
  • Contact: Jing LI
  • About author:LIN Haili, born in 1999, M. S. candidate. His research interests include federated learning.
  • Supported by:
    Strategic Priority Research Program of Chinese Academy of Sciences (A Class)(XDA19020102)

基于工作证明的联邦学习懒惰客户端识别方法

林海力, 李京()   

  1. 中国科学技术大学 计算机科学与技术学院,合肥 230027
  • 通讯作者: 李京
  • 作者简介:林海力(1999—),男,浙江温州人,硕士研究生,主要研究方向:联邦学习
  • 基金资助:
    中国科学院战略性先导科技专项(A类)(XDA19020102)

Abstract:

In today’s society with the growing demand for privacy protection, federated learning is receiving widespread attention. However, in federated learning, it is difficult for the server to supervise behaviors of clients, so that the existence of lazy clients poses a potential threat to the performance and fairness of federated learning. Aiming at the problem of how to identify lazy clients efficiently and accurately, a dual-task proof-of-work method based on backdoor was proposed, namely FedBD (FedBackDoor). In FedBD, additional backdoor tasks that are easier to detect were allocated by the server for the clients participating in federated learning, the backdoor tasks were trained by the clients based on the original training tasks, and the clients’ behaviors were supervised by the server indirectly through training status of the backdoor tasks. Experimental results show that FedBD has certain advantages over the classic federated averaging algorithm FedAvg and the advanced algorithm GTG-Shapley (Guided Truncation Gradient Shapley) on datasets such as MNIST and CIFAR10. On CIFAR10 dataset, when the proportion of lazy clients is 15%, FedBD improves the accuracy by more than 10 percentage points compared with FedAvg, and increases the accuracy by 2 percentage points compared with GTG-Shapley. Moreover, the average training time of FedBD is only 11.8% of that of GTG-Shapley, and the accuracy of FedBD in identifying lazy clients can exceed 99% when the proportion of lazy clients is 10%. It can be seen that FedBD can solve the problem of lazy clients being difficult to supervise.

Key words: federated learning, backdoor, lazy client, proof-of-work, data heterogeneity

摘要:

在对隐私保护的需求不断增长的当今社会,联邦学习正受到广泛关注。然而,在联邦学习中,服务器难以监管客户端的行为,致使懒惰客户端的存在为联邦学习的性能与公平性带来了潜在威胁。针对如何高效又准确地辨别懒惰客户端的问题,提出设置基于后门的双任务工作证明方法FedBD(FedBackDoor)。在FedBD中,服务器为参与联邦学习的客户端额外指定更易检测的后门任务,客户端在训练原任务的基础上训练后门任务,而服务器通过后门任务的训练情况间接监管客户端的行为。实验结果表明,在MNIST、CIFAR10等数据集上,相较于经典联邦平均算法FedAvg和先进算法GTG-Shapley(Guided Truncation Gradient Shapley),FedBD有一定优势。在CIFAR10数据集上,在懒惰客户端占比设置为15%时,FedBD比FedAvg的准确率提升可达10个百分点以上,比GTG-Shapley的准确率提升约2个百分点。此外,FedBD的平均训练时间仅为GTG-Shapley的11.8%,在懒惰客户端占比10%时辨别懒惰客户端的准确率可超过99%。可见,FedBD较好地解决了懒惰客户端难以监管的问题。

关键词: 联邦学习, 后门, 懒惰客户端, 工作证明, 数据异构

CLC Number: