FedNSA: Boosting Secure Aggregation by Assembling Differentially Private Noise Shares

Federated learning (FL, where multiple devices train AI models together without sharing raw data) faces privacy risks because adversaries can extract sensitive information from model updates. FedNSA is a new protocol that combines differential privacy (adding mathematical noise to hide individual data patterns), encryption, and multi-party computation (MPC, a technique where multiple parties jointly compute results without revealing their individual inputs) to protect model updates while reducing the communication and computational burden that makes secure aggregation impractical on resource-constrained devices like smartphones.