Selected Publications

1. Ciphertext-ciphertext matrix multiplication: fast for large matrices

   Eurocrypt 2025

   sole author

   We propose fast algorithms for multiplying large ciphertext matrices. In addition, we introduce fast algorithms for transposing large ciphertext matrices. The paper also presents lightweight algorithms that require small evaluation keys. This paper is included in my thesis.

2. Plaintext-ciphertext matrix multiplication and FHE bootstrapping: fast and fused

   Crypto 2024

   with Youngjin Bae, Jung Hee Cheon, Guillaume Hanrot, and Damien Stehlé

   We introduce fast algorithms for multiplying plaintext and ciphertext matrices. Our algorithms handle various matrix dimensions with or without precomputations. In addition, we accelerate FHE bootstrapping when several ciphertexts are bootstrapped at once. This paper is included in my thesis.

3. HERMES: efficient ring packing using MLWE ciphertexts and application to transciphering

   Crypto 2023

   with Youngjin Bae, Jung Hee Cheon, Jaehyung Kim, and Damien Stehlé

   Most HE schemes rely on either LWE problem or its ring variant (RLWE). We introduce HERMES, an efficient ring packing algorithm that converts the format between LWE and RLWE. Using HERMES, we also suggest a fast transciphering algorithm from LWE symmetric encryption to CKKS scheme.

4. Efficient homomorphic evaluation on large intervals

   IEEE TIFS 2022

   with Jung Hee Cheon and Wootae Kim

   Homomorphic evaluations generally incur an overhead. While knowing that data is confined to a narrow range can reduce the overhead, such constraints are not always applicable. In this paper, we propose an efficient method for homomorphic evaluation of several functions over large ranges.

For the complete list of my publications, please click here.