# FuseFSS: Efficient Secure LLM Inference with Function Secret Sharing

arXiv: https://arxiv.org/abs/2606.09551 · HTML: https://mlsanity.com/paper/2606.09551/

## Key facts

- Cited by 1 papers in the map (data through 14 Oct 2026).
- Builds on 6 of its 40 references that are in the map.
- First posted on arXiv 8 Jun 2026.

## Builds on (most cited first, 6 of 6)

- [Attention Is All You Need](https://mlsanity.com/paper/1706.03762/) (2017)
- [Language Models are Few-Shot Learners](https://mlsanity.com/paper/2005.14165/) (2020)
- [Layer Normalization](https://mlsanity.com/paper/1607.06450/) (2016)
- [CrypTFlow2: Practical 2-Party Secure Inference](https://mlsanity.com/paper/2010.06457/) (2020)
- [Converting Transformers to Polynomial Form for Secure Inference Over Homomorphic Encryption](https://mlsanity.com/paper/2311.08610/) (2023)
- [Ditto: Quantization-aware Secure Inference of Transformers upon MPC](https://mlsanity.com/paper/2405.05525/) (2024)

## Built on by (most cited first, 1 of 1)

- [A Graph-Based Analysis of Comparability, Scale, and Attribution in Private Transformer Inference](https://mlsanity.com/paper/2610.19607/) (2026)

## Abstract (arXiv)

Two-server secure inference allows a client to query a hosted large language model (LLM) without revealing prompts or embeddings. Recent GPU systems based on function secret sharing (FSS) make linear layers efficient, but fixed-point nonlinearities and helper operations remain a bottleneck because each operator is typically implemented as a bespoke protocol with its own comparisons, wrap-around corrections, and preprocessing material. We present FuseFSS, a compiler that replaces per-operator protocol design with a single compilation pipeline. For each scalar fixed-point operator, a compact specification lists its interval partition, low-degree arithmetic pieces, and required predicate bits. The compiler emits two batched FSS evaluations on the public masked value: one packed comparison that returns all predicate bits, and one vector interval lookup that returns the active coefficients and constants. Compared to the current state-of-the-art FSS-based GPU secure inference, FuseFSS preserves accuracy while achieving a 1.24×--1.50× end-to-end speedup and reducing online communication by 9%--16% on BERT and GPT-style models; preprocessing is also lighter, with 14%--23% lower key-generation time and 20%--24% smaller keys.