This paper presents \textit{OFHE}, an electro-optical accelerator designed to process Discretized TFHE (DTFHE) operations, which encrypt multi-bit messages and support homomorphic multiplications, lookup table operations and full-domain functional bootstrappings. While DTFHE is more efficient and versatile than other fully homomorphic encryption schemes, it requires 32-, 64-, and 128-bit polynomial multiplications, which can be time-consuming. Existing TFHE accelerators are not easily upgradable to support DTFHE operations due to limited datapaths, a lack of datapath bit-width reconfigurability, and power inefficiencies when processing FFT and inverse FFT (IFFT) kernels. Compared to prior TFHE accelerators, OFHE addresses these challenges by improving the DTFHE operation latency by 8.7\%, the DTFHE operation throughput by 57%, and the DTFHE operation throughput per Watt by 94%.
@article{arxiv.2405.11607,
title = {OFHE: An Electro-Optical Accelerator for Discretized TFHE},
author = {Mengxin Zheng and Cheng Chu and Qian Lou and Nathan Youngblood and Mo Li and Sajjad Moazeni and Lei Jiang},
journal= {arXiv preprint arXiv:2405.11607},
year = {2024}
}