Binarizing Split Learning for Data Privacy Enhancement and Computation Reduction

TL;DR

This paper introduces binarized split learning (B-SL) that significantly reduces computation and memory usage while enhancing privacy, making it suitable for lightweight IoT and mobile healthcare applications.

Contribution

The study proposes a novel B-SL approach with binarized local layers, combined with new privacy-enhancing techniques, to improve efficiency and privacy in split learning.

Findings

B-SL achieves up to 17.5x faster computation on mobile devices.

Memory and bandwidth requirements are reduced up to 32x.

B-SL effectively mitigates privacy leakage and resists feature-space hijacking attacks.

Abstract

Split learning (SL) enables data privacy preservation by allowing clients to collaboratively train a deep learning model with the server without sharing raw data. However, SL still has limitations such as potential data privacy leakage and high computation at clients. In this study, we propose to binarize the SL local layers for faster computation (up to 17.5 times less forward-propagation time in both training and inference phases on mobile devices) and reduced memory usage (up to 32 times less memory and bandwidth requirements). More importantly, the binarized SL (B-SL) model can reduce privacy leakage from SL smashed data with merely a small degradation in model accuracy. To further enhance the privacy preservation, we also propose two novel approaches: 1) training with additional local leak loss and 2) applying differential privacy, which could be integrated separately or concurrently into the B-SL model. Experimental results with different datasets have affirmed the advantages of the B-SL models compared with several benchmark models. The effectiveness of B-SL models against feature-space hijacking attack (FSHA) is also illustrated. Our results have demonstrated B-SL models are promising for lightweight IoT/mobile applications with high privacy-preservation requirements such as mobile healthcare applications.