An Overview of Federated Deep Learning Privacy Attacks and Defensive Strategies

Abstract

With the increased attention and legislation for data-privacy, collaborative machine learning (ML) algorithms are being developed to ensure the protection of private data used for processing. Federated learning (FL) is the most popular of these methods, which provides privacy preservation by facilitating collaborative training of a shared model without the need to exchange any private data with a centralized server. Rather, an abstraction of the data in the form of a machine learning model update is sent. Recent studies showed that such model updates may still very well leak private information and thus a more structured risk assessment is needed. In this chapter, we analyze existing vulnerabilities of FL and subsequently perform a literature review of the possible attack methods targeting FL privacy protection capabilities. These attack methods are then categorized by a basic taxonomy. Additionally, we provide a literature study of the most recent defensive strategies and algorithms for FL aimed to overcome these attacks. These defensive strategies are categorized by their respective underlying defense principle. The chapter advocates that the application of a single defensive strategy is not enough to provide adequate protection against all available attack methods.