Oblivious Message Retrieval
The Zcash Foundation has been looking into Oblivious Message Retrieval (OMR) to determine whether it offers a potential solution to the recent performance problems that have affected Zcash wallet users, and whether there are any advantages to be gained from implementing this in a Zcash context.
FROST Performance
In this post, we briefly describe the threshold signature scheme FROST, and present benchmark results for our FROST implementation. We also describe one optimization that greatly improves its speed, especially for scenarios with a large number of signers.
So You Want to Build an End-to-End Encrypted Web App
So it would be really nice if we could do browser-based end-to-end encrypted video calling, like we do between devices like a desktop app or a mobile app. We want this so that Zoom itself, or an outside party influencing Zoom or their infrastructure, cannot snoop on or interfere with these video calls. However, despite […]
Design Tradeoffs in Privacy-Preserving Contact Tracing
In our previous post, we talked about how the problem of building decentralized, privacy-preserving contact tracing systems is an opportunity to meaningfully apply cryptography to a pressing public health problem. That post described one effort, TraceTogether, but there are several other efforts in development. In this post, we’ll describe a cryptographic perspective on the contact tracing problem, […]
Let’s Develop Decentralized, Privacy-Preserving Contact Tracing
Over the last few months and especially the last few weeks, the spread of COVID-19 has created a massive health crisis at global scale. Healthcare infrastructure is being overwhelmed around the world. While data about the spread of the virus and its effects are still uncertain, projections about the potential effects of unchecked spread are […]
Composable Futures-based Batch Verification
In a previous post, we shared details on the new, fully asynchronous network stack we designed for Zebra, the Zcash Foundation’s forthcoming node implementation. In this post, I want to share an idea we’re hoping will help us achieve high performance and high code quality in a different area: cryptographic verification of data on the Zcash blockchain. […]
Accelerating SNARKs with FPGAs: Final Research Results
In July, the Foundation announced an FPGA acceleration research project. In September, FPGA engineer Ben Devlin wrapped up the engagement by presenting his work at the Taipei Ethereum Meetup. You can watch the talk on YouTube and see the slides on GitHub ? The code and documentation are also available in the GitHub repo. “We are laying the groundwork for bespoke […]