Cathie Yun

Cathie Yun

Applied Cryptographer, Security Engineer

Talks and presentations

Moving toward real-world deployment of FHE - NIST

December 14, 2022

Presentation, NIST Crypto Reading Club, Virtual

Video and Slides. I presented on Google’s work toward real-world deployment of Fully Homomorphic Encryption (FHE), at the NIST Crypto Reading Club. This talk provides an engineer’s perspective on deploying large scale systems with FHE, its practical challenges, and open problems. The talk highlights the importance of compilers in realizing FHE as a privacy tool. It also includes a deeper dive into the FHE transpiler open sourced by Google, its modular architecture, and how it can accelerate FHE research and software development.

Unlocking the potential of FHE - Google

September 19, 2022

Presentation, Safer With Google (Google internal security summit), Sunnyvale

Shruthi and I gave a talk at Safer With Google, the Google internal security summit, about our team’s work on making Fully Homomorphic Encryption (FHE) practical. The video and slides are not available to the public, but Googlers can view them at the internal golink: go/swg-summit.

Ask Me Anything: Cryptographers Panel

April 13, 2022

Presentation, Real World Cryptography 2022, Amsterdam

Video. I sat on an “Ask Me Anything” panel at Real World Crypto 2022 to talk about the relationship between cryptography research and its use in industry, give advice to folks starting out their cryptography career, and to defend the usefulness of blockchains (at least, as a way to fund really cool cryptography research).

Trust Tokens: How Much Do We Trust Them?

August 04, 2020

Presentation, 0x0G (Google's DEFCON event), Online

Video. This talk is a peek inside the cryptography security review process at Google, looking at the Trust Tokens protocol based on Privacy Pass. I reviewed this protocol before it was deployed, and it is now in use in Google Chrome help Chrome differentiate between bots and real users.

How Zero Knowledge Proofs Work

August 09, 2019

Presentation, DEFCON27 Crypto Village, Las Vegas, NV

Video. Zero knowledge proofs are powerful tools; come learn about how they work and what they enable! We’ll get down and dirty in the details of Bulletproofs, a zero knowledge proof protocol that doesn’t require trusted setup. I’ll walk you through the math/crypto of Bulletproofs, alongside my open-source implementation in Rust. You’ll walk away with an appreciation for zero knowledge proofs, a deeper understanding of Bulletproofs, and hopefully some interest in tinkering on or building systems with zero knowledge proof protocols yourself!

ZkVM: Fast, Private, Flexible Blockchain Contracts

June 23, 2019

Research Presentation, ZCon Annual Privacy Conference 2019, Split, Croatia

Video and Slides. In this talk, Oleg and I announce ZkVM, the zero-knowledge virtual machine. ZkVM is an experimental multi-asset blockchain architecture for scalable and confidential smart contracts.

R1CS and Smart Contracts with Bulletproofs

April 10, 2019

Research Presentation, 2nd ZKProof Workshop, Berkeley CA, USA

Video and Slides. In this talk, I discuss how we implemented the R1CS (rank one constraint system) API for flexibly programming proofs with the Bulletproofs zero knowledge proof system. I also discuss how to build a confidential assets protocol, as well as how to make a usable smart contract language, using that API. This talk is a precursor to the official release of ZkVM, the zero knowledge smart contract language that we developed using these techniques.

TxVM: A New Design for Blockchain Transactions

January 25, 2018

Research Presentation, Stanford Cyber Initiative, Stanford University

Video and Slides. In this talk, I announce TxVM, a powerful new design for blockchain transactions. TxVM seeks to achieve the expressiveness and flexibility of an imperative contract model such as Ethereum’s while maintaining the efficiency, safety, and scalability of a declarative transaction model such as Bitcoin’s.