·
·
·
I am a cryptography researcher at Ethereum Foundation. Previously, I was a postdoctoral researcher at UC Berkeley, hosted by Sanjam Garg. I obtained my Ph.D. in Mathematical Sciences at Seoul National University, advised by Jung Hee Cheon.
I am broadly interested in cryptography from theory to practice. Currently, my research focus is on cryptographic primitives for secure computation (e.g., homomorphic encryption, secure multiparty computation) and their applications (e.g., private database query).
Publications
Authors are listed in alphabetical order by last name, unless an asterisk (*) is indicated. [AMS Statement]
- *Lean-GAP: A Dataset of Formalized Graduate Algebra Problems
- A Cryptographic Framework for Proof of Personhood
- Qurrency: a quantum-secure, private, and auditable platform for digital assets
- Barely Doubly-Efficient SimplePIR
- Bypassing Prompt Guards in Production with Controlled-Release Prompting
- SophOMR: Improved Oblivious Message Retrieval from SIMD-Aware Homomorphic Compression
- *Verifiable PIR with Small Client Storage
- More Efficient Lattice-based OLE from Circuit-private Linear HE with Polynomial Overhead
- *Leveraging FPGAs for Homomorphic Matrix-Vector Multiplication in Oblivious Message Retrieval
- Bit Security as Cost to Demonstrate Advantage
- VeriSimplePIR: Verifiability in SimplePIR at No Online Cost for Honest Servers
- SIMD-Aware Homomorphic Compression and Application to Private Database Query
- *Asynchronous Federated Learning with Directed Acyclic Graph-based Blockchain in Edge Computing: Overview, Design, and Challenges
- Limits of Polynomial Packings for $\mathbb{Z}_{p^k}$ and $\mathbb{F}_{p^k}$
- On the Scaled Inverse of $(x^i - x^j)$ modulo Cyclotomic Polynomial of the form $\Phi_{p^s}(x)$ or $\Phi_{p^s q^t}(x)$
- *HELPSE: Homomorphic Encryption-based Lightweight Password Strength Estimation in a Virtual Keyboard System
- MHz2k: MPC from HE over $\mathbb{Z}_{2^k}$ with New Packing, Simpler Reshare, and Better ZKP
- *Accelerating Fully Homomorphic Encryption Through Architecture-Centric Analysis and Optimization
- Gimme That Model!: A Trusted ML Model Trading Protocol
- *Hardware Architecture of a Number Theoretic Transform for a Bootstrappable RNS-based Homomorphic Encryption Scheme
- Numerical Method for Comparison on Homomorphically Encrypted Numbers
- *FPGA-based Accelerators of Fully Pipelined Modular Multipliers for Homomorphic Encryption
- Efficient Identity-Based Encryption from LWR
- *A Secure SNP Panel Scheme using Homomorphically Encrypted K-mers without SNP Calling on the User Side
- *Logistic Regression Model Training based on the Approximate Homomorphic Encryption
- Privacy-Preserving Computations of Predictive Medical Models with Minimax Approximation and Non-Adjacent Form
Writings
Honors
- Distinguished Reviewer Award, IEEE S&P 2026 IEEE Symposium on Security and Privacy · 2026
- Sejong Science Fellowship National Research Foundation of Korea · 2024–2025
- Doctoral Dissertation Award (Best Award) Korean Mathematical Society · 2024
- Doctoral Dissertation Award (Best Award) College of Natural Sciences, Seoul National University · 2023
- Best Paper Runner-up, Asiacrypt 2019 (Invited to Journal of Cryptology) International Association for Cryptologic Research · 2019
- Global Ph.D. Fellowship National Research Foundation of Korea · 2018–2023
- First Place, iDASH Genomic Data Privacy & Security Competition (link) iDASH National Center (NIH) · 2017
Service
- Program Committee Asiacrypt (2025, 2026), IEEE S&P (2026), ACM CCS (2026), USENIX Security (2027)
- Editorial Board IACR CiC (2025)