Lawrence Roy ldr709@gmail.com Postdoc, IBM Research Zürich Updated: April 3, 2026

Research Interests

I research a range of topics related to secure multi-party computation, including oblivious transfer (OT), OT extension, garbled circuits, homomorphic secret sharing, and advanced lattice primitives. I am also interested in formal verification and proofs for cryptography and cybersecurity more generally.

Education

Thesis: “Communication-Efficient Secure Two-Party Computation From Minicrypt and OT”.
Advisor: Mike Rosulek.

Admitted following high school, undergraduate degree requirement waived.
Project: “A Complete Characterization of Security for Linicrypt Block Cipher Modes”.

Publications

I started my research in computer graphics. During my internship at IBM in 2018, I gained some experience in systems security, and its intersection with cryptography. I then switched fully to cryptography in 2019, though I maintain a side interest in systems security. These fields have different author ordering conventions.

Preprint Publications

Publications not in a peer-reviewed conference or journal. These are available only through IACR ePrint or other non-peer-reviewed repositories.

1.

New Upper and Lower Bounds for Perfectly Secure MPC. Ivan Damgård, Shravani Patil, Arpita Patra, and Lawrence Roy. 2025. url: https://eprint.iacr.org/2025/1206

2.

FAEST: Algorithm Specifications (Version 2.0). Carsten Baum, Ward Beullens, Lennart Braun, Cyprien Delpech de Saint Guilhem, Michael Klooß, Christian Majenz, Shibam Mukherjee, Emmanuela Orsini, Sebastian Ramacher, Christian Rechberger, Lawrence Roy, and Peter Scholl. Part of NIST PQC Digital Signature Schemes, Round 2. 2025. url: https://faest.info/faest-spec-v2.0.pdf

3.

Time-Based Cryptography From Weaker Assumptions: Randomness Beacons, Delay Functions and More. Damiano Abram, Lawrence Roy, and Mark Simkin. 2024. url: https://eprint.iacr.org/2024/769

Peer-Reviewed Publications

1.

“Slightly Sublinear Trapdoor Hash Functions and PIR from Low-Noise LPN”. Damiano Abram, Giulio Malavolta, and Lawrence Roy. In: TCC 2025. doi: 10.1007/978-3-032-12287-2_10. url: https://eprint.iacr.org/2025/416

2.

“Privately Constrained PRFs from DCR: Puncturing and Bounded Waring Rank”. Amik Raj Behera, Pierre Meyer, Claudio Orlandi, Lawrence Roy, and Peter Scholl. In: TCC 2025. doi: 10.1007/978-3-032-12287-2_11. url: https://eprint.iacr.org/2025/230

3.

“An Unstoppable Ideal Functionality for Signatures and a Modular Analysis of the Dolev-Strong Broadcast”. Ran Cohen, Jack Doerner, Eysa Lee, Anna Lysyanskaya, and Lawrence Roy. In: TCC 2025. doi: 10.1007/978-3-032-12290-2_22. url: https://eprint.iacr.org/2024/1807

4.

“Shorter, Tighter, FAESTer: Optimizations and Improved (QROM) Analysis for VOLE-in-the-Head Signatures”. Carsten Baum, Ward Beullens, Lennart Braun, Cyprien Delpech de Saint Guilhem, Michael Klooß, Christian Majenz, Shibam Mukherjee, Emmanuela Orsini, Sebastian Ramacher, Christian Rechberger, Lawrence Roy, and Peter Scholl. In: CRYPTO 2025. doi: 10.1007/978-3-032-01887-8_5. url: https://eprint.iacr.org/2026/164

5.

“Lower Bounds for Garbled Circuits from Shannon-Type Information Inequalities”. Jake Januzelli, Mike Rosulek, and Lawrence Roy. In: CRYPTO 2025. url: https://eprint.iacr.org/2025/876

6.

“Key-Homomorphic Computations for RAM: Fully Succinct Randomised Encodings and More”. Damiano Abram, Giulio Malavolta, and Lawrence Roy. In: CRYPTO 2025. doi: 10.1007/978-3-032-01881-6_8. url: https://eprint.iacr.org/2025/339

7.

“Silent Circuit Relinearisation: Sublinear-Size (Boolean and Arithmetic) Garbled Circuits from DCR”. Pierre Meyer, Claudio Orlandi, Lawrence Roy, and Peter Scholl. In: CRYPTO 2025. doi: 10.1007/978-3-032-01884-7_14. url: https://eprint.iacr.org/2025/245

8.

“Information-Theoretic Random-Index PIR”. Sebastian Kolby, Lawrence Roy, Jure Sternad, and Sophia Yakoubov. In: ITC 2025. doi: 10.4230/LIPIcs.ITC.2025.5. url: https://eprint.iacr.org/2025/1574

9.

“Succinct Oblivious Tensor Evaluation and Applications: Adaptively-Secure Laconic Function Evaluation and Trapdoor Hashing for All Circuits”. Damiano Abram, Giulio Malavolta, and Lawrence Roy. In: 57th ACM STOC. 2025. doi: 10.1145/3717823.3718164. url: https://eprint.iacr.org/2025/336

10.

“Under What Conditions Is Encrypted Key Exchange Actually Secure?” Jake Januzelli, Lawrence Roy, and Jiayu Xu. In: EUROCRYPT 2025. doi: 10.1007/978-3-031-91124-8_16. url: https://eprint.iacr.org/2024/324

11.

“Efficient Secure Communication over Dynamic Incomplete Networks with Minimal Connectivity”. Ivan Damgård, Divya Ravi, Lawrence Roy, Daniel Tschudi, and Sophia Yakoubov. In: TCC 2024. doi: 10.1007/978-3-031-78023-3_9. url: https://eprint.iacr.org/2024/972

12.

“Rate-1 Arithmetic Garbling From Homomorphic Secret Sharing”. Pierre Meyer, Claudio Orlandi, Lawrence Roy, and Peter Scholl. In: TCC 2024. doi: 10.1007/978-3-031-78023-3_3. url: https://eprint.iacr.org/2024/820

13.

“One Tree to Rule Them All: Optimizing GGM Trees and OWFs for Post-Quantum Signatures”. Carsten Baum, Ward Beullens, Shibam Mukherjee, Emmanuela Orsini, Sebastian Ramacher, Christian Rechberger, Lawrence Roy, and Peter Scholl. In: ASIACRYPT 2024. doi: 10.1007/978-981-96-0875-1_15. url: https://eprint.iacr.org/2024/490

14.

“Efficient Maliciously Secure Oblivious Exponentiations”. Carsten Baum, Jens Berlips, Walther Chen, Ivan Bjerre Damgård, Kevin M. Esvelt, Leonard Foner, Dana Gretton, Martin Kysel, Ronald L. Rivest, Lawrence Roy, Francesca Sage-Ling, Adi Shamir, Vinod Vaikuntanathan, Lynn Van Hauwe, Theia Vogel, Benjamin Weinstein-Raun, Daniel Wichs, Stephen Wooster, Andrew C. Yao, and Yu Yu. In: CiC (2024). doi: 10.62056/a66cy7qiu

15.

“Improved Reductions from Noisy to Bounded and Probing Leakages via Hockey-Stick Divergences”. Maciej Obremski, João Ribeiro, Lawrence Roy, François-Xavier Standaert, and Daniele Venturi. In: CRYPTO 2024. doi: https://doi.org/10.1007/978-3-031-68391-6_14. url: https://eprint.iacr.org/2024/1009

16.

“Succinct Homomorphic Secret Sharing”. Damiano Abram, Lawrence Roy, and Peter Scholl. In: EUROCRYPT 2024. doi: 10.1007/978-3-031-58751-1_11. url: https://eprint.iacr.org/2024/814

17.

“Publicly Verifiable Zero-Knowledge and Post-Quantum Signatures from VOLE-in-the-Head”. Carsten Baum, Lennart Braun, Cyprien Delpech de Saint Guilhem, Michael Klooß, Emmanuela Orsini, Lawrence Roy, and Peter Scholl. In: CRYPTO 2023. doi: 10.1007/978-3-031-38554-4_19. url: https://eprint.iacr.org/2023/996

18.

“Two-Round Stateless Deterministic Two-Party Schnorr Signatures from Pseudorandom Correlation Functions”. Yashvanth Kondi, Claudio Orlandi, and Lawrence Roy. In: CRYPTO 2023. doi: 10.1007/978-3-031-38557-5_21. url: https://eprint.iacr.org/2023/216

19.

“Faster coercion-resistant e-voting by encrypted sorting”. Diego F. Aranha, Michele Battagliola, and Lawrence Roy. In: Proceedings of E-Vote-ID 2023. https://e-vote-id.org/. url: https://eprint.iacr.org/2023/837

20.

“A Universally Composable PAKE with Zero Communication Cost (And Why It Shouldn’t Be Considered UC-Secure)”. Lawrence Roy and Jiayu Xu. In: PKC 2023. url: https://eprint.iacr.org/2022/1607

21.

“SoftSpokenOT: Quieter OT Extension from Small-Field Silent VOLE in the Minicrypt Model”. Lawrence Roy. In: CRYPTO 2022. doi: 10.1007/978-3-031-15802-5_23. url: https://eprint.iacr.org/2022/192

22.

“A Complete Characterization of Security for Linicrypt Block Cipher Modes”. Tommy Hollenberg, Mike Rosulek, and Lawrence Roy. In: CSF 2022 Computer Security Foundations Symposium. doi: 10.1109/CSF54842.2022.9919676. url: https://eprint.iacr.org/2022/1033

23.

“Batching Base Oblivious Transfers”. Ian McQuoid, Mike Rosulek, and Lawrence Roy. In: ASIACRYPT 2021. doi: 10.1007/978-3-030-92078-4_10. url: https://eprint.iacr.org/2021/682

24.

Honorable Mention for Best Paper!

“Three Halves Make a Whole? Beating the Half-Gates Lower Bound for Garbled Circuits”. Mike Rosulek and Lawrence Roy. In: CRYPTO 2021. doi: 10.1007/978-3-030-84242-0_5. url: https://eprint.iacr.org/2021/749

25.

“Large Message Homomorphic Secret Sharing from DCR and Applications”. Lawrence Roy and Jaspal Singh. In: CRYPTO 2021. doi: 10.1007/978-3-030-84252-9_23. url: https://eprint.iacr.org/2021/274

26.

“Minimal Symmetric PAKE and 1-out-of-N OT from Programmable-Once Public Functions”. Ian McQuoid, Mike Rosulek, and Lawrence Roy. In: ACM CCS 2020. doi: 10.1145/3372297.3417870. url: https://eprint.iacr.org/2020/1043

27.

“Practical Privacy-Preserving Authentication for SSH”. Lawrence Roy, Stanislav Lyakhov, Yeongjin Jang, and Mike Rosulek. In: USENIX Security 2022. url: https://eprint.iacr.org/2022/740

28.

“Confidential Computing for OpenPOWER”. Guerney D. H. Hunt, Ramachandra Pai, Michael V. Le, Hani Jamjoom, Sukadev Bhattiprolu, Rick Boivie, Laurent Dufour, Brad Frey, Mohit Kapur, Kenneth A. Goldman, Ryan Grimm, Janani Janakirman, John M. Ludden, Paul Mackerras, Cathy May, Elaine R. Palmer, Bharata Bhasker Rao, Lawrence Roy, William A. Starke, Jeff Stuecheli, Enriquillo Valdez, and Wendel Voigt. In: Proceedings of the Sixteenth European Conference on Computer Systems. 2021. url: https://doi.org/10.1145/3447786.3456243

29.

“Maximum Number of Transition Points in 3D Linear Symmetric Tensor Fields”. Yue Zhang, Lawrence Roy, Ritesh Sharma, and Eugene Zhang. In: Topological Methods in Data Analysis and Visualization V. 2020. url: linear_3d_tensor_field_transition_point.pdf

30.

“Mode Surfaces of Symmetric Tensor Fields: Topological Analysis and Seamless Extraction”. Botong Qu, Lawrence Roy, Yue Zhang, and Eugene Zhang. In: IEEE Transactions on Visualization and Computer Graphics (2020). url: https://arxiv.org/pdf/2009.04601

31.

“Multi-Scale Topological Analysis of Asymmetric Tensor Fields on Surfaces”. Fariba Khan, Lawrence Roy, Eugene Zhang, Botong Qu, Shih-Hsuan Hung, Harry Yeh, Robert S Laramee, and Yue Zhang. In: IEEE Transactions on Visualization and Computer Graphics (2019). url: https://web.engr.oregonstate.edu/~zhange/images/2Dasymmetric_multiscale.pdf

32.

“Robust and Fast Extraction of 3D Symmetric Tensor Field Topology”. Lawrence Roy, Prashant Kumar, Yue Zhang, and Eugene Zhang. In: IEEE Transactions on Visualization and Computer Graphics (2018). url: http://web.engr.oregonstate.edu/~zhange/images/3DTensorTopology_Detection.pdf

33.

“Tensor Field Design in Volumes”. Jonathan Palacios, Lawrence Roy, Prashant Kumar, Chen-Yuan Hsu, Weikai Chen, Chongyang Ma, Li-Yi Wei, and Eugene Zhang. In: ACM Trans. Graph. (2017). issn: 0730-0301. doi: 10.1145/3130800.3130844. url: https://web.engr.oregonstate.edu/~zhange/images/3Dtensor_design.pdf

34.

“Interactive Design and Visualization of Branched Covering Spaces”. Lawrence Roy, Prashant Kumar, Sanaz Golbabaei, Yue Zhang, and Eugene Zhang. In: IEEE Transactions on Visualization and Computer Graphics (2017). doi: 10.1109/TVCG.2017.2744038. url: http://web.engr.oregonstate.edu/~zhange/images/Paper_BCSVis.pdf

35.

“Construction and Visualization of Branched Covering Spaces”. Sanaz Golbabaei, Lawrence Roy, Prashant Kumar, and Eugene Zhang. In: SIGGRAPH ASIA 2016 Technical Briefs. Macau, 2016. doi: 10.1145/3005358.3005367

Presentations

Recorded Talks

Shorter, Tighter, FAESTer: Optimizations and Improved (QROM) Analysis for VOLE-in-the-Head Signatures
Video ($19min$)
Silent Circuit Relinearisation: Sublinear-Size (Boolean and Arithmetic) Garbled Circuits from DCR
Video ($21min$)

Rate-1 Arithmetic Garbling from Homomorphic Secret-Sharing
Video ($15min$)

Improved Reductions from Noisy to Bounded and Probing Leakages via Hockey-Stick Divergences
Video ($20min$)

Distributed Discrete Logarithms and Applications
Presented jointly with Pierre Meyer.
Pierre’s Part ($36min$), My Part ($34min$)

Succinct Homomorphic Secret Sharing
Video ($22min$)

One Tree to Rule Them All: Optimizing GGM Trees and OWFs for Post-Quantum Signatures
Video ($20min$)

A Universally Composable PAKE with Zero Communication Cost (And Why It Shouldn’t Be Considered UC-Secure)
Video ($17min$)

SoftSpokenOT: Quieter OT Extension From Small-Field Silent VOLE in the Minicrypt Model
Video ($23min$)

Communication-Efficient Secure Two-Party Computation From Minimal Assumptions
Video ($16min$)

SoftSpokenOT: Communication–Computation Tradeoffs in OT Extension
Video ($23min$)

Three Halves Make a Whole? Beating the Half-Gates Lower Bound for Garbled Circuits
Prerecorded Video ($25min$), Live Presentation ($10min$)

Minimal Symmetric PAKE and 1-out-of-N OT from Programmable-Once Public Functions ($10min$)

Honors and Awards

Academic

Capture The Flag (CTF) Competitions¹

Service

Program Committees

Sorted by conference year, not submission year.

Ad Hoc Reviewing

Other