Exploring Federated Learning Dynamics for Black-and-White-Box DNN Traitor Tracing

As deep learning applications become more preva-lent, the need for extensive training examples raises concerns for sensitive, personal, or proprietary data. To overcome this, Federated Learning (FL) enables collaborative model training across distributed data-owners, but it introduces challenges in safeguarding model ownership and identifying the origin in case of a leak. Building upon prior work, this paper explores the adaptation of black-and-white traitor tracing watermarking to FL classifiers, addressing the threat of collusion attacks from different data-owners. This study reveals that leak-resistant white-box fingerprints can be directly implemented without a significant impact from FL dynamics, while the black-box fingerprints are drastically affected, losing their traitor tracing capabilities. To mitigate this effect, we propose increasing the number of black-box salient neurons through dropout regularization. Though there are still some open problems to be explored, such as analyzing non-i.i.d. datasets and over-parameterized models, results show that collusion-resistant traitor tracing, identifying all data-owners involved in a suspected leak, is feasible in an FL framework, even in early stages of training.