Public transaction history in blockchains represents one of their key features which, alongside immutability, aim to provide an alternative to CeFi. However, this transparency comes at a price: privacy. As a result, different solutions have been proposed, that preserve privacy while maintaining all the other benefits of blockchain technology, but there currently isn't a one-size-fits-all answer to this problem. For example, zero knowledge proofs convey the validity of a transaction batch without sharing any other details, but the underlying arithmetic circuits are both complex as well as computational intensive. Umbra proposes a system that relies completely on elliptic curve cryptography, employing multiple private-public key pairs to achieve stealth payments.

We were joined by Ben DiFrancesco, founder & CEO of ScopeLift, to talk about Umbra's privacy preserving stealth token transfer system and if the need for privacy on blockchains outweighs any implicit UX frictions.

Topics covered in this episode:

Ben’s backgroundUmbra's missionHow Umbra worksNon-interactive key distributionPotential solutions (& trade-offs) for Umbra's computational intensityGenerating private-public key pairs by the Umbra smart contractUser experience (UX) for senders and receiversFee structure for deterring griefing attacksHow Umbra works for ERC20 tokens & NFTsPrivacy preserving withdrawals from stealth addressesPrivacy vs. UX frictionSmart wallets & account abstractionPrioritising privacyEpisode links:

Ben DiFrancesco on TwitterUmbra on TwitterScopeLift on TwitterThis episode is hosted by Friederike Ernst. Show notes and listening options: epicenter.tv/496