Collaborative Research: CNS Core: Small: Privacy by Memory Design
Project Synopsis
Differential privacy (DP) has been widely
accepted as the de facto technique for protecting data privacy. Despite the decade-long
research efforts on DP, there still exists a critical research problem that has been
largely overlooked, that is all existing DP studies are grounded on the hypothesis that
software can easily and faithfully sample and add noises from a probability
distribution. However, this hypothesis is being constantly challenged by recent findings
about its privacy violation and by the growing demand of privacy protection in low-end
devices that may lack high-level software libraries. Hence, this project's innovative
research angle is to realize DP mechanisms directly on embedded memories, which are
ubiquitous in modern electronic devices.
The fundation of this project is based on the physical property of embedded memeories - data bits stored in memory cells will be corrupted when the supply voltage of the memory is reduced below the nominal voltage. As shown in Figure 1, the cell failure rate is dependent on transistor sizes, supply voltages and several other parameters. This project aims to design and optimize memory architecture and peripheral circuits to control cell failures to let stored bits be corrupted in a way that conforms to the DP notions. Towards this goal, this project proposes three research thrusts:
In our prior studies
[TIFS'22], we developed a prototype to demonstrate the realization of Local DP (LDP) in SRAM
memory and the achievement of significant power savings on memory read/write processes.
Our idea was based on a key observation that memory cells exhibit failures at sub-nominal
supply voltages, which perturbs data bits (e.g., 0 to 1) stored therein. To utilize this characteristic towards the LDP
realization, we designed a new memory architecture with a hybrid 6T-8T cell structure
that achieves heterogeneous cell failures when operating at sub-nominal supply voltages.
With such design, when data is read out from the memory, some bit positions can be controlled
to flip their bit values while others can have their bit values remain unaltered. The cell failures (or
bit flipping) are properly controlled via runtime power control to realize the randomized
response on some specific binary bits of the stored data, thereby ensuring LDP on the
original data. In the meantime, we purposefully rendered cell failures to the least significant
bits to minimize the utility loss.
Personnel and Collaborators
|
Dr. Na Gong (site-PI)
W. Nicholson Associate Professor Department of Electrical and Computer Engineering University of South Alabama Email: nagong at southalabama dot edu |
Research Progress
-
[1]
Query Integrity Meets Blockchain: A Privacy-Preserving
Verification Framework for Outsourced Encrypted Data
S. Jiang, J. Liu, Y. Liu, J. Chen, L. Wang, and Y. Zhou, to appear at IEEE Transactions on Services Computing (IEEE TSC).
[2] Towards Anonymous yet Accountable Authentication for Public Wi-Fi Hotspot Access with Permissionless Blockchains
Y. Niu, L. Wei, J. Liu, Y. Fang, to appear at IEEE Transactions on Vehicular Technology (IEEE TVT).
Education and Outreach Activities
under development
Disclaimer
Any opinions, findings, and conclusions or recommendations expressed in this
material are those of the author(s) and do not necessarily reflect the views of the National
Science Foundation.